The personal website of Scott W Harden
June 13th, 2012

Resuming Life

I'm staring deeply into a large, ominous, empty white text box on my screen as a small vertical text cursor blinks, staring back at me. I faintly remember writing my first blog entry eleven years ago (to the week), as a 15 year old kid typing on a keyboard in the middle of the night. Every time I log-in to write on my website, I see the same cursor, monotonous in its dependable, unvarying appearance. What does the cursor see in me? Definitely not the same person it saw the last time I logged-in. What collection of words can even begin to describe the jumble that's in my head? My name is Scott Harden, my future is changing before my eyes, and I've chosen to use this website to continue to document my life as it unfolds.

It's been 298 days since I've last written. For anyone who's been through a hard time, part of getting better is acting like ones self again. For me, that's doing the things that I used to do: designing circuits, writing code, building radios, and documenting my projects on my website. Me, starting to write again - forcing myself to write again - is a step in a positive direction, and an indication that I am starting to be okay. My intention is to resume building and sharing projects on this website like I used to.

I feel it is important to address some of the recent changes in my life in a clear manner. I don't want to just resume posting code and pictures of circuits all the sudden without acknowledging the serious issues that I've dealt with and am continuing to deal with. It's important that it's obvious that (a) these things happened, (b) I'm working to be okay with them, and (c) I'm not ignoring them. I have noticed that ignoring serious issues by pretending that they do not exist is one of the most dangerous and destructive coping mechanisms a person can exhibit. People behave this way around me often, but I, in an effort to improve my situation, refuse to ignore my challenges. I will attempt to describe a few of the highlights of the last several months of my life. It's certainly not an exhaustive list, but it touches on a few of the significant experiences I have gone through, changes which have affected me, and a few of the events that made me happy since I last wrote here.

I began a new Ph.D. program in Neuroscience through the Interdisciplinary Program in Biomedical Science through the College of Medicine at the University of Florida. I am currently in my 4th year of dental school (in my 10th year of college currently), and I'm considering starting a new program from scratch. Rather than throw-away my dental degree (which I've been working on for several years and spent quite a lot of money to pursue), I am seeking a combined D.M.D/Ph.D. degree. This will allow me to graduate with a degree in dental medicine (D.M.D.) through the UF College of Dentistry about the same time I get my Ph.D. in Neuroscience through the UF College of Medicine. I begin this August, and I couldn't be more excited. As my Google Scholar author page reports, I've had excellent research experience in the past, and I'm eager to begin life again as a biomolecular graduate student. I have yet to decide the specific direction of my research, but if I could do anything in the world, I would try to find a project which lets me dip into bioinformatics.

It looks like I'm kind of sick. To make a long story short, I'm in a strange diagnostic limbo where it's looking like I may have a pretty serious, rare, and somewhat difficult to diagnose form of cancer (stage 4 peripheral T-cell lymphoma), but at the same time it seems there is a chance it could be a weird, rare ailment that's not as serious (an obscure autoimmune condition or abnormal presentation of chronic infection). The type of cancer it is currently proposed to be is pretty bad, and people usually don't live too long after their diagnosis. Intriguingly, my symptoms and clinical presentation don't reflect the rapidly destructive nature commonly associated with this disease, leaving open the possibility that it might not be that form of cancer after all. I have hard, enlarged lymph nodes (with abnormal histology demonstrated by 1 needle biopsy and 2 separate surgeries) in all quadrants of my body, and have a lot of fatigue (which I combat with large volumes of coffee). Other than that, I'm relatively normal (physically, at least). The picture to the right is me on the first visit to the oncologist. I didn't take it too seriously. I kept thinking (and still do to some degree) there's no way it could be that bad. I mean, who my age gets sick like this? And right on the heels of losing my wife? It's too coincidental, it can't be that serious! Realistically we still don't know for sure exactly what it is, and it's too early to tell how this will affect my life. It's a strange experience grappling with the idea that I might only live a few more years, knowing at the same time that my cancer might not be that bad and I may have a long, relatively normal life. I will know more a few months from now. In the mean time, I'm content planning my life as if I will be completely fine (which is certainly may be the case), and if I get sick along the way I'll re-evaluate my situation if the need arises. For now, I'm quite positive. If anyone were to get a one in a million disease and get through it unscathed, it would be me!

I've had some interesting medical experiences over the last few months. The left image is my PET CT, which depicts active metabolism. I was injected with radioactive glucose, and the tissues that work hard absorb it and appear as "hot" on the image. I was lying down (for about 30 minutes), so the only active organs should be my heart and brain. The kidneys/bladder are illuminated because it filtered some of the material from the blood. Actively growing tumors also uptake glucose, and are labeled on this image. While the majority of my tumors are benign and slow growing, this image shows a few rapidly growing tumors: one on my upper right leg (which was removed with surgery #1, second picture), one small one at the base of my neck (which was removed with surgery #2, third picture), and a few scattered ones under each of my arms. The active ones were removed to aid in diagnosis, and it's not feasible to remove all of the affected lymph nodes. The last picture shows me after my most recent surgery coming out of anesthesia. I don't even remember it being taken - I was pretty out of it at the time, as you can infer from the photo :)

Many people have asked how I have been doing since Angelina died. Unexpectedly losing a spouse at any age is difficult, but at such a young age (I was 25, she was 24, we were married for 4 years) it's even harder to rationalize sometimes. No words I write can even begin to describe the complex array of emotions I carry. Although I wish things had turned-out differently, I still feel fortunate to have had Angelina in my life, and I know unquestionably that I am a better person for having known her, and am thankful we got to share as much as we did. The picture on the right is the last one I have of us together. (I'm in the blue shirt, she's in the black shirt). It was taken about two weekends before she died. We went with a group of my dental school classmates to Islands of Adventure (part of Universal Studios) in Orlando. If you had told me then that I would be a widower in a couple weeks, I couldn't have even begun to comprehend it. I will always miss her, but I know that she would not want me to destroy my life because she is gone. In a note she wrote for me the day she died, she said "I love you, Scott, more than you will ever know." It's a phrase I remember and repeat in my mind every day, and it's given me comfort over the last several months. I know that I will always carry part of her with me.

Several people have e-mailed me in concern due to the fact that I had stopped posting over the last few months. Again, I was surprised and honored the unexpected support I've been getting over the internet from people I don't really even know. The following quote is one that came in this morning, "It has been a while since I have last visited and I really hope you’re doing OK since your last post. I can’t pretend to remotely know how you feel, even with the time that has passed since then. Just wanted to say I wish you well and miss your posts. All I can say is that I know that there have been periods of time in my life where I put down the soldering iron due to life… even for a couple of years. But, I always come back around because its part of who I am… and I hope it will be for you as well. --Jeremy"

The truth is, when Angelina died, life stopped. I stopped answering email, I stopped adding to my website, I stopped making phone calls, I even distanced myself from my own family for a while. Slowly, one by one, I'm resuming these activities. A few months ago, I unpacked my electronics workstation in my new apartment. It was a little premature, as I only worked at my station 1 day and took a few more months before I came back to it, but now it's a weekly process. For a long time I felt guilty even thinking about picking-up my silly projects again. I felt that, after everything she and I had gone through, it seemed fickle. With a little time and some self-reflection, I realized that Angelina encouraged me to do these things throughout our marriage. I remember her telling me that she went to college and bragged "my husband is on Hackaday". I told her that my academic publications on PubMed are more impressive, and I'll always remember her response: "Yeah, but you get more excited every time you make it on hack-a-day". I remember this and remind myself that, if she were here, I think she'd still continue to encourage me to do what I enjoy. While silly little projects might not seem significant, they do make me happy, and I think she would be proud of me for working on them.

Angelina left a few special reminders on my workbench. A few months after she died, and as I would unpacking my workstation again, I noticed a carving she made in my workbench. I almost threw away this table when I moved, and I'm so glad I didn't. I think Angelina carved it with a car key, probably on the day this post was made, when I left her unattended for a while soldering at my station. I also found a message she wrote on my roll of solder. I didn't remember seeing it before, so I imagine it was something she wrote the last few days she was alive. It is really special to me.

One of the things I've done that's really helped me a lot is to get out of my comfort zone a little bit and go places and do things I've never done before, often on a whim. This has led me to have a lot of a lot of fantastic experiences, and give me some new things to occupy myself with and remind me that there's still a lot of life out there left to live. Over the last several months, I tried to minimize the amount of time I spent doing things I'd done before. I noticed that the more time I spent doing the same old things, the more I felt like a part of me was missing, and the worse I felt. Changing scenery and being in new places, it felt less like something was missing, and began letting me establish the feeling of being okay on my own. I stayed away from Gainesville as much as I could, stayed away from family as much as I could (sorry mom and dad if you read this one day), and kept the amount of time I spent interacting with my old friends from dental school to a minimum. For some reason, nothing made me feel worse inside than being around my old environment, and avoiding it for a while was my way of trying to heal. For several months, this behavior was the only thing that made me feel better. Luckily, within the last few weeks, things have started to settle down, and I'm a little more comfortable settling-back into some of my old environments. I'm going to toss-in a collection of random photos from the last several months. I'm not going to describe them in detail - it's more an indication that yes, I'm alive, and yes, I'm getting out there a little. A few days after my wife died, I got a new apartment and moved in with a dental school classmate. His name is Ray, and he's a pretty cool guy. I'm very lucky to have him. He moved out of his old apartment and into my apartment in less than a week's notice.

I marched in the UF homecoming parade with the University of Florida Gator Amateur Radio Club.

I participated in the "out of the darkness" walk for suicide awareness sponsored by the Suicide Survivors of Northeast Florida group.

I operated as net control for Gator Amateur Radio Society during the 5 points of life "relay for life" marathon (official site).

I practiced advanced suturing techniques utilizing a pig jaw. I actually messed it up pretty badly... oops? Next time I'll do it on a person. Scary, right?

Here's a picture with me beside my friend Bill, W4HBK. He and his wife were wonderfully kind in offering me a place to stay over a portion of the Christmas break. Bill is a fellow QRSS'er (who mans the Pensacola Snapper) and we had a great time working with antennas, looking at QRP equipment, and testing 160M WSPR. It seemed like a random thing for me to do (drive 6 hours to spend several days with a family I hadn't met before), but was a wonderful experience and I am thankful to both of them.

I started getting into electronics again a couple months ago. I learned how to etch PCBs at home (using the toner transfer method with hot ferric chloride) and am making digital QRSS transmitter designs. My signal is the one that looks drunk, swerving all over the QRSS road. The picture of me by a fence was in Ocala at a gokart racetrack. It was the week I found out I was sick. Also pictured is my QRSS transmitter, a somewhat novel design using no potentiometers. The oscillator is a 74HC240 with a varactor diode, allowing frequency adjustment via a potentiometer, and a lowpass-filtered PWM line from the microcontroller to provide modulation. The degree of modulation is adjustable via the second potentiometer.

I get my hair cut in my friend's kitchen. His name is Don and he is a dental student too. My hair cuts are $5.

I operated the W4DFU radio station during the CQWW contest.

I also visited a museum. Can you believe I went my entire life without ever actually seeing a dinosaur skeleton in person?

The photo from space is the result of a a successful retrieval of a camera that was launched back in August. It was placed on a high altitude balloon launched the same day Angelina and I drove to Orlando for the weekend (the next day the photo of us above was taken). It took photos as it ascended, then landed, and it was lost for several months. Some boys playing in the woods found it and gave it to their mom, who contacted us. The photos are pretty impressive, and I'll post details in a future entry.

This picture of me sitting on the couch is from Christmas at a big family get-together. That was an experience. Like I mentioned above, my wife's death hurts the most when I'm in a place where I feel she should be. When I do "old things", and go to the places we used to go together, and be in situations where we always were together, her absence is unignorably overwhelming and painful. I imagine holidays will continue to hurt for a while. I don't know how I got this photo, did my sister take it? Anyhow, that's how that goes.

Transitioning back into internet productivity, I will share some code which I utilized to create today's entry. I wanted to rapidly browse through numerous high resolution images to choose which ones to share, but pressing the left and right arrows was too slow (some of the large images took 5+ seconds to load). I therefore copied all of the images (*.jpg) created within the last 6 months and copied them into a single folder. I whipped-up a script to use ImageMagick's convert feature (which is available for linux and windows) to create 300px wide thumbnails and place them on a static HTML page for viewing in a browser. Each thumbnail was clickable, revealing the original, large image. Below is the script I used to do this.

import os
out="<html><body>"
fnames=os.listdir("./")
fnames.sort() # alphabetize them
for fname in fnames:
if ".jpg" in fname or ".JPG" in fname:
if "sml_" in fname: continue
cmd="convert -resize 300 %s sml_%s"%(fname,fname)
print cmd #note that this requires ImageMagik installed
os.system(cmd)
out+='<a href="%s">'%(fname)
out+='<img src="sml_%s"></a><br>'%(fname)
out+='%s<br><br><br>n'%(os.path.split(fname)[1])
out+="</body></html>"
f=open("pics.html",'w')
f.write(out)
f.close()
print "DONE"

What do I plan to do from here? I'm starting my PhD program in August, and I plan to hit it hard. I feel lucky that I have the opportunity to study biomedical science again. I'm holding my breath for it to start, and am looking forward to having something academically and intellectually challenging to devote myself to. I plan to continue making my electronics and programming projects, and publishing them here on my website. If my health changes, it all might change, but I'm holding out that I'll be okay. All in all, I've lived through an unbelievably rough year, but I look forward to getting back into the game.

Markdown source code last modified on January 18th, 2021
---
title: Resuming Life
date: 2012-06-13 10:41:33
---

# Resuming Life

__I'm staring deeply into a large, ominous, empty white text box on my screen as a small vertical text cursor blinks, staring back at me.__ I faintly remember writing my first blog entry eleven years ago (to the week), as a 15 year old kid typing on a keyboard in the middle of the night. Every time I log-in to write on my website, I see the same cursor, monotonous in its dependable, unvarying appearance.  What does the cursor see in me? Definitely not the same person it saw the last time I logged-in. What collection of words can even begin to describe the jumble that's in my head? My name is Scott Harden, my future is changing before my eyes, and I've chosen to use this website to continue to document my life as it unfolds.

__It's been 298 days since I've last written.__ For anyone who's been through a hard time, part of getting better is acting like ones self again. For me, that's doing the things that I used to do: designing circuits, writing code, building radios, and documenting my projects on my website. Me, starting to write again - forcing myself to write again - is a step in a positive direction, and an indication that I am starting to be okay. My intention is to resume building and sharing projects on this website like I used to.

__I feel it is important to address some of the recent changes in my life in a clear manner.__ I don't want to just resume posting code and pictures of circuits all the sudden without acknowledging the serious issues that I've dealt with and am continuing to deal with. It's important that it's obvious that (a) these things happened, (b) I'm working to be okay with them, and (c) I'm not ignoring them. I have noticed that ignoring serious issues by pretending that they do not exist is one of the most dangerous and destructive coping mechanisms a person can exhibit. People behave this way around me often, but I, in an effort to improve my situation, refuse to ignore my challenges. I will attempt to describe a few of the highlights of the last several months of my life. It's certainly not an exhaustive list, but it touches on a few of the significant experiences I have gone through, changes which have affected me, and a few of the events that made me happy since I last wrote here.

<div class="text-center img-border">

[![](12-2_thumb.jpg)](12-2.jpg)

</div>

__I began a new [Ph.D. program in Neuroscience](http://idp.med.ufl.edu/about/neuroscience/) through the Interdisciplinary Program in Biomedical Science through the College of Medicine at the University of Florida.__ I am currently in my 4th year of dental school (in my 10th year of college currently), and I'm considering starting a new program from scratch. Rather than throw-away my dental degree (which I've been working on for several years and spent quite a lot of money to pursue), I am seeking a combined D.M.D/Ph.D. degree. This will allow me to graduate with a degree in dental medicine (D.M.D.) through the UF College of Dentistry about the same time I get my Ph.D. in Neuroscience through the UF College of Medicine. I begin this August, and I couldn't be more excited. As my [Google Scholar author page](http://scholar.google.com/citations?hl=en&user=egCaj-AAAAAJ&oi=sra) reports, I've had excellent research experience in the past, and I'm eager to begin life again as a biomolecular graduate student. I have yet to decide the specific direction of my research, but if I could do anything in the world, I would try to find a project which lets me dip into [bioinformatics](http://en.wikipedia.org/wiki/Bioinformatics).

<div class="text-center img-border">

[![](2012-04-23_08.57.33_thumb.jpg)](2012-04-23_08.57.33.jpg)

</div>

__It looks like I'm kind of sick.__ To make a long story short, I'm in a strange diagnostic limbo where it's looking like I may have a pretty serious, rare, and somewhat difficult to diagnose form of cancer (stage 4 [peripheral T-cell lymphoma](http://en.wikipedia.org/wiki/Peripheral_T-cell_lymphoma-Not-Otherwise-Specified)), but at the same time it seems there is a chance it could be a weird, rare ailment that's not as serious (an obscure autoimmune condition or abnormal presentation of chronic infection). The type of cancer it is currently proposed to be is pretty bad, and people usually don't live too long after their diagnosis. Intriguingly, my symptoms and clinical presentation don't reflect the rapidly destructive nature commonly associated with this disease, leaving open the possibility that it might not be that form of cancer after all. I have hard, enlarged lymph nodes (with abnormal histology demonstrated by 1 needle biopsy and 2 separate surgeries) in all quadrants of my body, and have a lot of fatigue (which I combat with large volumes of coffee). Other than that, I'm relatively normal (physically, at least). The picture to the right is me on the first visit to the oncologist. I didn't take it too seriously. I kept thinking (and still do to some degree) there's no way it could be that bad.  I mean, who my age gets sick like this? And right on the heels of losing my wife? It's too coincidental, it can't be that serious! Realistically we still don't know for sure exactly what it is, and it's too early to tell how this will affect my life. It's a strange experience grappling with the idea that I might only live a few more years, knowing at the same time that my cancer might not be that bad and I may have a long, relatively normal life. I will know more a few months from now. In the mean time, I'm content planning my life as if I will be completely fine (which is certainly may be the case), and if I get sick along the way I'll re-evaluate my situation if the need arises. For now, I'm quite positive. If anyone were to get a one in a million disease and get through it unscathed, it would be me!

<div class="text-center img-border img-small">

[![](4-pet-ct-too_thumb.jpg)](4-pet-ct-too.jpg)
[![](IMG_5851_thumb.jpg)](IMG_5851.jpg)

</div>

__I've had some interesting medical experiences over the last few months.__ The left image is my [PET CT](http://en.wikipedia.org/wiki/PET-CT), which depicts active metabolism. I was injected with radioactive glucose, and the tissues that work hard absorb it and appear as "hot" on the image. I was lying down (for about 30 minutes), so the only active organs should be my heart and brain. The kidneys/bladder are illuminated because it filtered some of the material from the blood. Actively growing tumors also uptake glucose, and are labeled on this image. While the majority of my tumors are benign and slow growing, this image shows a few rapidly growing tumors: one on my upper right leg (which was removed with surgery #1, second picture), one small one at the base of my neck (which was removed with surgery #2, third picture), and a few scattered ones under each of my arms. The active ones were removed to aid in diagnosis, and it's not feasible to remove all of the affected lymph nodes. The last picture shows me after my most recent surgery coming out of anesthesia. I don't even remember it being taken - I was pretty out of it at the time, as you can infer from the photo :)

<div class="text-center img-border">

[![](IMG_0440_thumb.jpg)](IMG_0440.jpg)

</div>

**Many people have asked** how I have been doing since Angelina died. Unexpectedly losing a spouse at any age is difficult, but at such a young age (I was 25, she was 24, we were married for 4 years) it's even harder to rationalize sometimes. No words I write can even begin to describe the complex array of emotions I carry. Although I wish things had turned-out differently, I still feel fortunate to have had Angelina in my life, and I know unquestionably that I am a better person for having known her, and am thankful we got to share as much as we did. The picture on the right is the last one I have of us together. (I'm in the blue shirt, she's in the black shirt). It was taken about two weekends before she died. We went with a group of my dental school classmates to Islands of Adventure (part of Universal Studios) in Orlando. If you had told me then that I would be a widower in a couple weeks, I couldn't have even begun to comprehend it. I will always miss her, but I know that she would not want me to destroy my life because she is gone. In a note she wrote for me the day she died, she said "I love you, Scott, more than you will ever know." It's a phrase I remember and repeat in my mind every day, and it's given me comfort over the last several months. I know that I will always carry part of her with me.

__Several people have e-mailed me in concern due to the fact that I had stopped posting over the last few months.__ Again, I was surprised and honored the unexpected support I've been getting over the internet from people I don't really even know. The following quote is one that came in this morning, "_It has been a while since I have last visited and I really hope you’re doing OK since your last post. I can’t pretend to remotely know how you feel, even with the time that has passed since then. Just wanted to say I wish you well and miss your posts. All I can say is that I know that there have been periods of time in my life where I put down the soldering iron due to life… even for a couple of years. But, I always come back around because its part of who I am… and I hope it will be for you as well. --Jeremy_"

__The truth is__, when Angelina died, life stopped. I stopped answering email, I stopped adding to my website, I stopped making phone calls, I even distanced myself from my own family for a while. Slowly, one by one, I'm resuming these activities. A few months ago, I unpacked my electronics workstation in my new apartment. It was a little premature, as I only worked at my station 1 day and took a few more months before I came back to it, but now it's a weekly process. For a long time I felt guilty even thinking about picking-up my silly projects again. I felt that, after everything she and I had gone through, it seemed fickle. With a little time and some self-reflection, I realized that Angelina encouraged me to do these things throughout our marriage. I remember her telling me that she went to college and bragged "my husband is on Hackaday". I told her that my academic publications on PubMed are more impressive, and I'll always remember her response: "Yeah, but you get more excited every time you make it on hack-a-day". I remember this and remind myself that, if she were here, I think she'd still continue to encourage me to do what I enjoy. While silly little projects might not seem significant, they do make me happy, and I think she would be proud of me for working on them.

<div class="text-center img-border img-medium">

[![](angelina_carve_thumb.jpg)](angelina_carve.jpg)

</div>

<div class="text-center img-border img-small">

[![](angelina_solder_thumb.jpg)](angelina_solder.jpg)

</div>

<div class="text-center img-border img-medium">

[![](angelina_soldering_thumb.jpg)](angelina_soldering.jpg)

</div>

__Angelina left a few special reminders on my workbench.__ A few months after she died, and as I would unpacking my workstation again, I noticed a carving she made in my workbench. I almost threw away this table when I moved, and I'm so glad I didn't. I think Angelina carved it with a car key, probably [on the day this post was made](http://www.swharden.com/blog/2011-02-20-rf-workshop-launched/), when I left her unattended for a while soldering at my station. I also found a message she wrote on my roll of solder. I didn't remember seeing it before, so I imagine it was something she wrote the last few days she was alive. It is really special to me.

<div class="text-center img-border">

[![](09_thumb.jpg)](09.jpg)

</div>

__One of the things I've done__ that's really helped me a lot is to get out of my comfort zone a little bit and go places and do things I've never done before, often on a whim. This has led me to have a lot of a lot of fantastic experiences, and give me some new things to occupy myself with and remind me that there's still a lot of life out there left to live. Over the last several months, I tried to minimize the amount of time I spent doing things I'd done before. I noticed that the more time I spent doing the same old things, the more I felt like a part of me was missing, and the worse I felt. Changing scenery and being in new places, it felt less like something was missing, and began letting me establish the feeling of being okay on my own. I stayed away from Gainesville as much as I could, stayed away from family as much as I could (sorry mom and dad if you read this one day), and kept the amount of time I spent interacting with my old friends from dental school to a minimum. For some reason, nothing made me feel worse inside than being around my old environment, and avoiding it for a while was my way of trying to heal. For several months, this behavior was the _only_ thing that made me feel better. Luckily, within the last few weeks, things have started to settle down, and I'm a little more comfortable settling-back into some of my old environments. I'm going to toss-in a collection of random photos from the last several months. I'm not going to describe them in detail - it's more an indication that yes, I'm alive, and yes, I'm getting out there a little. A few days after my wife died, I got a new apartment and moved in with a dental school classmate. His name is Ray, and he's a pretty cool guy. I'm very lucky to have him. He moved out of his old apartment and into my apartment in less than a week's notice. 

<div class="text-center img-border">

[![](01_thumb.jpg)](01.jpg)

</div>

__I marched in the UF homecoming parade__ with the University of Florida [Gator Amateur Radio Club](http://gatorradio.org/). 

<div class="text-center img-border">

[![](02_thumb.jpg)](02.jpg)

</div>

__I participated in the "out of the darkness" walk for suicide awareness__ sponsored by the [Suicide Survivors of Northeast Florida group](http://www.neflsurvivors.org/community-walk.aspx). 

<div class="text-center img-border">

[![](03_thumb.jpg)](03.jpg)

</div>

**I operated as [net control](http://en.wikipedia.org/wiki/Amateur_radio_net) for [Gator Amateur Radio Society](http://www.gars.net/)** during the [5 points of life "relay for life"](http://www.wcjb.com/local-news/2012/02/5-points-life-marathon-relay) marathon ([official site](http://www.fivepointsoflife.com/)).

<div class="text-center img-border">

[![](10_thumb.jpg)](10.jpg)

</div>

__I practiced advanced suturing techniques utilizing a pig jaw.__ I actually messed it up pretty badly... oops? Next time I'll do it on a person. Scary, right? 

<div class="text-center img-border">

[![](14_thumb.jpg)](14.jpg)

</div>

**Here's a picture with me beside my friend Bill, W4HBK.** He and his wife were wonderfully kind in offering me a place to stay over a portion of the Christmas break. Bill is a fellow QRSS'er (who mans the [Pensacola Snapper](http://pensacolasnapper.blogspot.com/)) and we had a great time working with antennas, looking at QRP equipment, and testing 160M WSPR. It seemed like a random thing for me to do (drive 6 hours to spend several days with a family I hadn't met before), but was a wonderful experience and I am thankful to both of them.

<div class="text-center img-border">

[![](26_thumb.jpg)](26.jpg)

</div>

<div class="text-center img-border img-micro">

[![](25_thumb.jpg)](25.jpg)
[![](27_thumb.jpg)](27.jpg)
[![](28_thumb.jpg)](28.jpg)
[![](30_thumb.jpg)](30.jpg)
[![](24_thumb.jpg)](24.jpg)
[![](31_thumb.jpg)](31.jpg)
[![](011_thumb.jpg)](011.jpg)

</div>

__I started getting into electronics again a couple months ago.__ I learned how to etch PCBs at home (using the toner transfer method with hot ferric chloride) and am making digital QRSS transmitter designs. My signal is the one that looks drunk, swerving all over the QRSS road. The picture of me by a fence was in Ocala at a gokart racetrack. It was the week I found out I was sick. Also pictured is my QRSS transmitter, a somewhat novel design using no potentiometers. The oscillator is a 74HC240 with a varactor diode, allowing frequency adjustment via a potentiometer, and a lowpass-filtered PWM line from the microcontroller to provide modulation. The degree of modulation is adjustable via the second potentiometer.

<div class="text-center img-border img-medium">

![](2011-12-04_12.55.16.jpg)

</div>

I get my hair cut in my friend's kitchen. His name is Don and he is a dental student too. My hair cuts are $5. 

<div class="text-center img-border img-small">

[![](IMG_0284_thumb.jpg)](IMG_0284.jpg)

</div>

I operated the W4DFU radio station during the CQWW contest. 

<div class="text-center img-border img-medium">

[![](DSC_6218_thumb.jpg)](DSC_6218.jpg)

</div>

I also visited a museum. Can you believe I went my entire life without ever actually seeing a dinosaur skeleton in person? 

<div class="text-center img-border">

![](space.jpg)

</div>

__The photo from space__ is the result of a a successful retrieval of a camera that was launched back in August. It was placed on a high altitude balloon launched the same day Angelina and I drove to Orlando for the weekend (the next day the photo of us above was taken). It took photos as it ascended, then landed, and it was lost for several months. Some boys playing in the woods found it and gave it to their mom, who contacted us. The photos are pretty impressive, and I'll post details in a future entry. 

<div class="text-center img-border img-small">

[![](IMG_6603_thumb.jpg)](IMG_6603.jpg)

</div>

**This picture** of me sitting on the couch is from Christmas at a big family get-together. That was an experience. Like I mentioned above, my wife's death hurts the most when I'm in a place where I feel she should be. When I do "old things", and go to the places we used to go together, and be in situations where we always were together, her absence is unignorably overwhelming and painful. I imagine holidays will continue to hurt for a while. I don't know how I got this photo, did my sister take it? Anyhow, that's how that goes. 

<div class="text-center img-border">

[![](2012-03-14-23.03.53_thumb.jpg)](2012-03-14-23.03.53.jpg)

</div>

__Transitioning back into internet productivity, I will share some code__ which I utilized to create today's entry. I wanted to rapidly browse through numerous high resolution images to choose which ones to share, but pressing the left and right arrows was too slow (some of the large images took 5+ seconds to load). I therefore copied all of the images (*.jpg) created within the last 6 months and copied them into a single folder. I whipped-up a script to use ImageMagick's convert feature (which is available for linux and windows) to create 300px wide thumbnails and place them on a static HTML page for viewing in a browser. Each thumbnail was clickable, revealing the original, large image. Below is the script I used to do this.

```python
import os
out="<html><body>"
fnames=os.listdir("./")
fnames.sort() # alphabetize them
for fname in fnames:
if ".jpg" in fname or ".JPG" in fname:
if "sml_" in fname: continue
cmd="convert -resize 300 %s sml_%s"%(fname,fname)
print cmd #note that this requires ImageMagik installed
os.system(cmd)
out+='<a href="%s">'%(fname)
out+='<img src="sml_%s"></a><br>'%(fname)
out+='%s<br><br><br>n'%(os.path.split(fname)[1])
out+="</body></html>"
f=open("pics.html",'w')
f.write(out)
f.close()
print "DONE"
```

__What do I plan to do from here?__ I'm starting my PhD program in August, and I plan to hit it hard. I feel lucky that I have the opportunity to study biomedical science again. I'm holding my breath for it to start, and am looking forward to having something academically and intellectually challenging to devote myself to. I plan to continue making my electronics and programming projects, and publishing them here on my website. If my health changes, it all might change, but I'm holding out that I'll be okay.  All in all, I've lived through an unbelievably rough year, but I look forward to getting back into the game.

<div class="text-center img-border">

[![](DSC_5878_thumb.jpg)](DSC_5878.jpg)

</div>
April 16th, 2012

First Diagnosis

In April 2012 I had some alarming symptoms and visited an oncologist for the first time. Symptoms included lymphadenopathy, weight loss, night sweats. This picture was taken just before my first doctor visit, and I’m in scrubs because I was a dental student at the time (I hadn’t started the DMD/PhD program yet). After several blood tests and two surgical biopsies I was eventually diagnosed with non-Hodgkin’s lymphoma (NHL). More specifically, Lennert’s Lymphoma, a rare lymphoepithelioid variant of peripheral T-cell lymphoma in the not otherwise specified category T-cell lymphomas.

I found one of K. Lennert’s early publications from 1986 especially interesting. There are earlier publications, but this one is open-access. Its title describes condition as “a monoclonal proliferation of helper T cells“, and in its text further characterizes it as “special variant of Hodgkin’s disease characterized by a high percentage of epithelioid cells and rarely containing the Reed-Sternberg cells characteristic of classical Hodgkin’s disease.”

Markdown source code last modified on January 18th, 2021
---
title: First Diagnosis
date: 2012-04-16 21:00:00
tags: med
---

# First Diagnosis

**In April 2012 I had some alarming symptoms and visited an oncologist for the first time.** Symptoms included lymphadenopathy, weight loss, night sweats. This picture was taken just before my first doctor visit, and I’m in scrubs because I was a dental student at the time (I hadn’t started the DMD/PhD program yet). After several blood tests and two surgical biopsies I was eventually diagnosed with [non-Hodgkin’s lymphoma (NHL)](https://g.co/kgs/yBJEYd). More specifically, Lennert’s Lymphoma, a rare lymphoepithelioid variant of peripheral T-cell lymphoma in the [not otherwise specified category](https://en.wikipedia.org/wiki/Peripheral_T-cell_lymphoma_not_otherwise_specified) T-cell lymphomas.

<div class="text-center img-border">

[![](visit1_thumb.jpg)](visit1.jpg)

</div>

**I found one of K. Lennert’s [early publications](http://www.bloodjournal.org/content/bloodjournal/68/3/663.full.pdf) from 1986 especially interesting.** There are earlier publications, but this one is open-access. Its title describes condition as “a monoclonal proliferation of helper T cells“, and in its text further characterizes it as “special variant of Hodgkin’s disease characterized by a high percentage of epithelioid cells and rarely containing the Reed-Sternberg cells characteristic of classical Hodgkin’s disease.”

![](https://www.youtube.com/embed/6ih0GTBGq7A)
August 23rd, 2011

We Love and Will Miss You, Angelina

As many of you know, my wife Angelina Harden unexpectedly passed away a couple days ago (Saturday, Aug 20, 2011). I'd like to thank all of our friends for their encouraging words. This is an extremely hard time for her family, my family, and me, and I appreciate the outpouring of support and encouragement.

Angelina's funeral was held in Jackson, Tennessee (the home town of much of Angelina's family and friends from her past) on September 10th, 2011. A memorial service was held in Gainesville, Florida (mostly attended by my family and college students from my dental school and Angelina's nursing school) on September 25, 2011. Both services were amazing, and I thank everybody who worked to make them so wonderful - it was a truly beautiful way to remember Angelina. Anelisse Martinez (a dental school classmate, and friend of Angelina and me) sang to an instrumental version of all 3 songs. For the last song, she was accompanied by Dennis Beliveau (another dental school classmate, and friend of Angelina and me). Dennis also sang Tears in Heaven, by Eric Clapton. These songs, in combination with the wonderful messages shared by Angelina's friends, made the service a joyful and moving experience. I'm fortunate to be surrounded by so many wonderful people. I ask for your continued thoughts for Angelina's family, her friends, and me - Angelina was loved so much, and her passing is hard for everyone who knew her. Thank you for your kindness.

Markdown source code last modified on January 18th, 2021
---
title: We Love and Will Miss You, Angelina
date: 2011-08-23 01:08:43
---

# We Love and Will Miss You, Angelina

__As many of you know, my wife Angelina Harden unexpectedly passed away a couple days ago__ (Saturday, Aug 20, 2011). I'd like to thank all of our friends for their encouraging words. This is an extremely hard time for her family, my family, and me, and I appreciate the outpouring of support and encouragement.

__Angelina's funeral__ was held in Jackson, Tennessee (the home town of much of Angelina's family and friends from her past) on September 10th, 2011. A memorial service was held in Gainesville, Florida (mostly attended by my family and college students from my dental school and Angelina's nursing school) on September 25, 2011. Both services were amazing, and I thank everybody who worked to make them so wonderful - it was a truly beautiful way to remember Angelina. Anelisse Martinez (a dental school classmate, and friend of Angelina and me) sang to an instrumental version of all 3 songs. For the last song, she was accompanied by Dennis Beliveau (another dental school classmate, and friend of Angelina and me). Dennis also sang Tears in Heaven, by Eric Clapton.  These songs, in combination with the wonderful messages shared by Angelina's friends, made the service a joyful and moving experience. I'm fortunate to be surrounded by so many wonderful people. I ask for your continued thoughts for Angelina's family, her friends, and me - Angelina was loved so much, and her passing is hard for everyone who knew her.  Thank you for your kindness.

<div class="text-center img-border">

![](snow.jpg)
![](angelina3.jpg)
![](angelina.jpg)
![](angelina2.jpg)

</div>
August 14th, 2011

High School Students' High Altitude Balloon #2

Last year a group of high school students, in collaboration with a seminar course on Space Systems sponsored by the University of Florida's Student Science Training Program (SSTP), gained some real-world experience planning, building, and launching a research payload to the edge of space – all in a couple weeks! Last year's high altitude balloon launch was covered on my website, and the radio transmitter I built for it was featured on this Hack-A-Day post. Unlike last year's payload, whose only homebrew device was the radio transmitter, this year's payload had equipment we assembled ourselves, and instead of launching from NASA we launched from the UF football stadium! There were a couple problems along the way, and the payload hasn't been recovered (yet), but it was a fun project and we all learned a lot along the way!

Update: project video

Below is a panoramic photo right before the launch - see our balloon on the right? So cool!

Our goal was to take photos from the edge of space, and log temperature, pressure, humidity, and GPS coordinates along the way. On-board were a radio transmitter, an Arduino with a GPS shield, and an Android phone to take pictures every few seconds.

Android details: Most of the Android development was handled by UF student Richard along with high school students Benji, Tyler, Michael, and Kevin. Their GitHub project is here:https://github.com/rich90usa/AndroidSensorLogger. Also note that the automatic photo capture utilized Photo Log Lite. We also used GPSLogger to handle logging GPS to SD. "Both of these programs were chosen for their ability to run in the background - and do so reliably by using the 'correct' Android supported methods of doing so." -- Richard

Our code used the phone's text-to-speech engine to speak out an encoded version of every 90th new GPS coordinate. The data was encoded by connecting every number (0-9) to a word the NATO phonetic alphabet. The code also used text-to-speech to have the phone speak out the phone's altitude data. --Benji

The device consisted of 4 main components: a payload (the styrofoam box in which all of the electrical equipment was housed), a radar reflector (hanging off the bottom of the payload, to help make this object visible to aircraft), a parachute (at the top, made of bio-degradable plastic), and the balloon itself which measured about 6 feet wide when inflated at ground level (supposedly it reaches approximately 30 feet wide at high altitudes before it bursts). Once the balloon bursts, the parachute fills with air and the device floats back to earth.

Kunal demonstrates the effectiveness of our parachute with a scientific "run test"!

The radio communication system we used this year were a little more commercial than last year. Due to my limited time availability (I had an oral surgery rotation all week the week before launch), I chose to get something pre-packaged. My intent was to use FRS (those little 500mW family radio service radios) to send GPS data back to earth, but I later (after launch) did a little more research and realized that it probably wasn't the most legal way to do it. However, it was extremely cost effective (amateur radio transmitters and RF transmitter modules are quite pricey). For about the cost of a pizza, we were able to interface a FRS radio to the android phone, and the phone ran a program which polled its GPS, turned coordinates into NATO letter abbreviations, and spoke them through the speaker line. The FRS radio with VOX (voice operated transmit) sensed audio and transmitted accordingly. Although it worked very well, I later learned that this may not have been legal in the US because, although FRS doesn't require a user license and is legal to use anywhere as long as you use its stock antenna, I violated the rule that it cannot be operated above a certain height (20m I think?). Note that this should not be replicated, and probably shouldn't have been done in the first place. I know I'll take a lot of heat over this, but it's in the past now and will be done differently in the future.

Here are some photos right before the launch. It was a sunny day at the UF football stadium! The Android phone is taped the the outside of the box and takes pictures every few seconds, storing them on a micro SD card. Inside the box is an Arduino with GPS shield, and the FRS radio transmitter.

After launch the balloon ascended at a rate of about 500ft/min. It spat out GPS data often, and altitude (not encoded with NATO abbreviations) was the easiest to hear as I walked from the UF football stadium to the UF Gator Amateur Radio Club to use their equipment (namely an AZEL-rotor-controlled 70cm yagi antenna attached to an I-Com 706) to listen in as the balloon ascended... but not before a group photo!

Here we are in the station... let's get to work!

The results were a bit disappointing, as we believe the Android phone froze/crashed about 10,000 feet in the air! Since that was the device which generated the audio fed into the transmitter, when that phone died, the transmitter stopped transmitting, and we didn't hear anything else from the transmitter ever again! We included contact information in the payload and it's possible it will be found one day and we will be contacted about it. If this is the case, we'll view the SD cards and see the full GPS log and pictures from the edge of space! Until then, we can only cross our fingers and hope for the best. Either way we had a blast, and learned a lot along the way. Next time we can be better prepared for a solid recovery!

Here's audio of the device's last words when it was about 10,000 feet in the air: lastwords.mp3

Overall we had an awesome time! I'd like to thank everyone who helped with this project, especially UF students Richard, Kunal, Dante, and all of the SSTP high school students!

Markdown source code last modified on January 18th, 2021
---
title: High School Students' High Altitude Balloon #2
date: 2011-08-14 18:36:12
tags: amateur radio
---

# High School Students' High Altitude Balloon #2

__Last year a group of high school students,__ in collaboration with a seminar course on Space Systems sponsored by the University of Florida's [Student Science Training Program (SSTP)](http://www.cpet.ufl.edu/sstp/default.html), gained some real-world experience planning, building, and launching a research payload to the edge of space – all in a couple weeks!  Last year's high altitude balloon launch was [covered on my website](http://www.swharden.com/blog/2010-07-14-high-altitude-balloon-transmitter/), and the radio transmitter I built for it was featured on [this Hack-A-Day post](http://hackaday.com/2010/07/27/200-mile-rf-transmitter-and-high-altitude-balloon/). Unlike last year's payload, whose only homebrew device was the radio transmitter, this year's payload had equipment we assembled ourselves, and instead of launching from NASA we launched from the UF football stadium! There were a couple problems along the way, and the payload hasn't been recovered (yet), but it was a fun project and we all learned a lot along the way!

**Update:** [project video](http://vimeo.com/27447092)

<div class="text-center img-border">

[![](group_thumb.jpg)](group.jpg)

</div>

Below is a panoramic photo right before the launch - see our balloon on the right? So cool!

<div class="text-center img-border">

[![](pan_thumb.jpg)](pan.jpg)

</div>

__Our goal was to take photos from the edge of space, and log temperature, pressure, humidity, and GPS coordinates along the way.__ On-board were a radio transmitter, an Arduino with a GPS shield, and an Android phone to take pictures every few seconds.

__Android details:__ Most of the Android development was handled by UF student Richard along with high school students Benji, Tyler, Michael, and Kevin. Their GitHub project is here:<https://github.com/rich90usa/AndroidSensorLogger>. Also note that the automatic photo capture utilized [Photo Log Lite](http://www.appbrain.com/app/photo-log-lite/com.keepknocking.PhotoLogLite). We also used [GPSLogger](http://mendhak.github.com/gpslogger/") to handle logging GPS to SD. _"Both of these programs were chosen for their ability to run in the background - and do so reliably by using the 'correct' Android supported methods of doing so." -- Richard_

>  Our code used the phone's text-to-speech engine to speak out an encoded version of every 90th new GPS coordinate. The data was encoded by connecting every number (0-9) to a word the [NATO phonetic alphabet](http://en.wikipedia.org/wiki/NATO_phonetic_alphabet). The code also used text-to-speech to have the phone speak out the phone's altitude data. --Benji

<div class="text-center img-border">

[![](DSC_6013_thumb.jpg)](DSC_6013.jpg)
[![](IMG_2095_thumb.jpg)](IMG_2095.jpg)

</div>

__The device consisted of 4 main components:__ a payload (the styrofoam box in which all of the electrical equipment was housed), a radar reflector (hanging off the bottom of the payload, to help make this object visible to aircraft), a parachute (at the top, made of bio-degradable plastic), and the balloon itself which measured about 6 feet wide when inflated at ground level (supposedly it reaches approximately 30 feet wide at high altitudes before it bursts).  Once the balloon bursts, the parachute fills with air and the device floats back to earth.

<div class="text-center img-border">

[![](DSC_6009_thumb.jpg)](DSC_6009.jpg)

</div>

__Kunal demonstrates the__ effectiveness of our parachute with a scientific "run test"!

<div class="text-center img-border">

[![](DSC_6015_thumb.jpg)](DSC_6015.jpg)

</div>

__The radio communication system we used this year__ were a little more commercial than last year. Due to my limited time availability (I had an oral surgery rotation all week the week before launch), I chose to get something pre-packaged. My intent was to use FRS (those little 500mW family radio service radios) to send GPS data back to earth, but I later (after launch) did a little more research and realized that it probably wasn't the most legal way to do it. However, it was extremely cost effective (amateur radio transmitters and RF transmitter modules are quite pricey). For about the cost of a pizza, we were able to interface a FRS radio to the android phone, and the phone ran a program which polled its GPS, turned coordinates into NATO letter abbreviations, and spoke them through the speaker line. The FRS radio with VOX (voice operated transmit) sensed audio and transmitted accordingly. Although it worked very well, I later learned that this may not have been legal in the US because, although FRS doesn't require a user license and is legal to use anywhere as long as you use its stock antenna, I violated the rule that it cannot be operated above a certain height (20m I think?). Note that this should not be replicated, and probably shouldn't have been done in the first place. I know I'll take a lot of heat over this, but it's in the past now and will be done differently in the future.

<div class="text-center img-border">

[![](DSC_6016_thumb.jpg)](DSC_6016.jpg)
[![](DSC_6042_thumb.jpg)](DSC_6042.jpg)
[![](DSC_6049_thumb.jpg)](DSC_6049.jpg)
[![](DSC_6071_thumb.jpg)](DSC_6071.jpg)

</div>

__Here are some photos right before the launch.__ It was a sunny day at the UF football stadium! The Android phone is taped the the outside of the box and takes pictures every few seconds, storing them on a micro SD card. Inside the box is an Arduino with GPS shield, and the FRS radio transmitter.

<div class="text-center img-border img-small">

[![](DSC_6079_thumb.jpg)](DSC_6079.jpg)
[![](DSC_6119_thumb.jpg)](DSC_6119.jpg)
[![](DSC_6132_thumb.jpg)](DSC_6132.jpg)
[![](pan_thumb.jpg)](pan.jpg)
[![](panZoomed_thumb.jpg)](panZoomed.jpg)
[![](DSC_6145_thumb.jpg)](DSC_6145.jpg)

</div>

![](https://www.youtube.com/embed/BozzCpdTJUk)

__After launch the balloon ascended at a rate of about 500ft/min.__ It spat out GPS data often, and altitude (not encoded with NATO abbreviations) was the easiest to hear as I walked from the UF football stadium to the UF [Gator Amateur Radio Club](http://gatorradio.org) to use their equipment (namely an AZEL-rotor-controlled 70cm yagi antenna attached to an I-Com 706) to listen in as the balloon ascended... but not before a group photo!

<div class="text-center img-border">

[![](DSC_6151_thumb.jpg)](DSC_6151.jpg)

</div>

__Here we are in the station... let's get to work!__

![](https://www.youtube.com/embed/98SHxyvsGB4)

<div class="text-center img-border">

[![](IMG_2118_thumb.jpg)](IMG_2118.jpg)

</div>

__The results were a bit disappointing,__ as we believe the Android phone froze/crashed about 10,000 feet in the air! Since that was the device which generated the audio fed into the transmitter, when that phone died, the transmitter stopped transmitting, and we didn't hear anything else from the transmitter ever again!  We included contact information in the payload and it's possible it will be found one day and we will be contacted about it. If this is the case, we'll view the SD cards and see the full GPS log and pictures from the edge of space! Until then, we can only cross our fingers and hope for the best. Either way we had a blast, and learned a lot along the way. Next time we can be better prepared for a solid recovery!

__Here's audio of the device's last words__ when it was about 10,000 feet in the air: [lastwords.mp3](lastwords.mp3)

__Overall we had an awesome time!__ I'd like to thank everyone who helped with this project, especially UF students Richard, Kunal, Dante, and all of the SSTP high school students!
August 14th, 2011

High Altitude Balloon Transmitter Prototype

It's been my goal for quite some time to design a simple, easy-to-replicate transmitter for high altitude balloon telemetry transmission. I'm quite satisfied by what I came up with because it's very simple, cheap, easy to code for, and easy to change frequency. I'd say the most common alternative is a handheld amateur radio transmitter which starts around $60, requires an amateur radio license, and typically output 5W of FM on 144MHz (2m) or 440MHz (70cm). Fancier handheld radios are capable of transmitting APRS packets, and use established base station repeaters to listen to these frequencies, decode the packets, and update an internet database about current location information. Although it's quite fancy, elegant, and technical (and expensive), I desire a much simpler, cheaper, disposable option! If my balloon lands in the Atlantic ocean, I don't want to be out $100+ of radio equipment! This alternative is about $7.

Here's my solution. I don't normally build things on perf-board (I prefer sloppy Manhattan construction), but since this might go near the edge of space and be jerked around in turbulent winds, I figured it would be a nice and strong way to assemble it. Anyhow, it uses a can crystal oscillator as the frequency source. These things are pretty cool, because they're very frequency stable, even with changing temperatures.

The can oscillator (28.704MHz, selected to be in a rarely-used region of the 10m amatuer radio allocation which I'm licensed to use, call sign AJ4VD) outputs 5V square waves which I use to drive two successive class C amplifiers. The signal can be shunted to ground between the two stages by a third "control" transistor, which allows micro-controller control over the final amplifier. Although it may have seemed logical to simply supply/cut power from the oscillator to key the transmitter, I decided against it because that can oscillator takes 20ms to stabilize, and I didn't think that was fast enough for some encoding methods I wish to employ!

Although during my tests I power the device from my bench-top power supply (just a few LM3805 and LM3812 regulators in a fancy case), it's designed to be run off 3xAAA batteries (for logic) and a 9V battery (for the transmitter). I could have probably used a regulator to drop the 9V to 5V for the MCU and eliminated some extra weight, but I wonder how low the 9V will dip when I draw a heavy RF load? The 3xAAAs seemed like a sure bet, but quite at the expense of weight. I should consider the regulator option further... [ponders]

There's the device in action while it was in a breadboard. I've since wired it up in a perf board (pictured) and left it to transmit into a small string of wire inside my apartment as an antenna as I went to the UF Gator Amateur Radio Club (a few miles away) and tried to tune into it. It produced a stunningly beautiful signal! I can't wait for its first test on a high altitude balloon! Here it's transmitting CW Morse code the words "scott rocks", separated by appropriate call sign identification every 10 minutes, AJ4VD, my amateur radio license... of course!

Above is what the audio sounded like with a narrow CW filter (awesome, right?), and a 3KHz wide USB configuration. I think this should be more than enough to carry us through a mission, and aid in direction finding of a landed payload!

Notes about filtering: The output of this transmitter is quite harmonic-rich. The oscillator produces square waves for goodness' sake! The class C amplifier smooths a bit of that out, but you still need some low-pass filtering, not shown on the schematic. I think for my purposes a 3-pole Chebyshev filter will suffice, but just keep this in mind in case you replicate my design. You certainly don't want to be transmitting out of band! Below is the output of the transmitter viewed on my scope. It's suspiciously smooth, which leads me to wonder about the accuracy of my scope! I really should get a spectrum analyzer.

Markdown source code last modified on January 18th, 2021
---
title: High Altitude Balloon Transmitter Prototype
date: 2011-08-14 18:42:59
tags: amateur radio, circuit, old
---

# High Altitude Balloon Transmitter Prototype

__It's been my goal for quite some time__ to design a simple, easy-to-replicate transmitter for high altitude balloon telemetry transmission. I'm quite satisfied by what I came up with because it's very simple, cheap, easy to code for, and easy to change frequency.  I'd say the most common alternative is a handheld amateur radio transmitter which starts around $60, requires an amateur radio license, and typically output 5W of FM on 144MHz (2m) or 440MHz (70cm). Fancier handheld radios are capable of transmitting [APRS](http://en.wikipedia.org/wiki/Automatic_Packet_Reporting_System) packets, and use established base station repeaters to listen to these frequencies, decode the packets, and update an internet database about current location information. Although it's quite fancy, elegant, and technical (and expensive), I desire a much simpler, cheaper, disposable option! If my balloon lands in the Atlantic ocean, I don't want to be out $100+ of radio equipment! This alternative is about $7.

<div class="text-center img-border">

[![](DSCN1718_thumb.jpg)](DSCN1718.jpg)

</div>

__Here's my solution.__ I don't normally build things on perf-board (I prefer sloppy Manhattan construction), but since this might go near the edge of space and be jerked around in turbulent winds, I figured it would be a nice and strong way to assemble it.  Anyhow, it uses a can crystal oscillator as the frequency source. These things are pretty cool, because they're very frequency stable, even with changing temperatures.

<div class="text-center img-border">

[![](DSCN1701_thumb.jpg)](DSCN1701.jpg)

</div>

__The can oscillator (28.704MHz, selected to be in a rarely-used region of the 10m amatuer radio allocation which I'm licensed to use, call sign AJ4VD) outputs 5V square waves which I use to drive two successive class C amplifiers.__ The signal can be shunted to ground between the two stages by a third "control" transistor, which allows micro-controller control over the final amplifier. Although it may have seemed logical to simply supply/cut power from the oscillator to key the transmitter, I decided against it because that can oscillator takes 20ms to stabilize, and I didn't think that was fast enough for some encoding methods I wish to employ!

<div class="text-center img-border">

[![](DSCN1717_thumb.jpg)](DSCN1717.jpg)

</div>

__Although during my tests I power the device from my bench-top power supply__ (just a few LM3805 and LM3812 regulators in a fancy case), it's designed to be run off 3xAAA batteries (for logic) and a 9V battery (for the transmitter). I could have probably used a regulator to drop the 9V to 5V for the MCU and eliminated some extra weight, but I wonder how low the 9V will dip when I draw a heavy RF load? The 3xAAAs seemed like a sure bet, but quite at the expense of weight. I should consider the regulator option further... [ponders]

![](https://www.youtube.com/embed/rRatJBAMgdg)

__There's the device in action while it was in a breadboard.__ I've since wired it up in a perf board (pictured) and left it to transmit into a small string of wire inside my apartment as an antenna as I went to the UF Gator Amateur Radio Club (a few miles away) and tried to tune into it. It produced a stunningly beautiful signal! I can't wait for its first test on a high altitude balloon!  Here it's transmitting CW Morse code the words "scott rocks", separated by appropriate call sign identification every 10 minutes, AJ4VD, my amateur radio license... of course!

* [cw.mp3](http://www.SWHarden.com/blog/images/cw.mp3)

* [usb.mp3](http://www.SWHarden.com/blog/images/usb.mp3)

__Above is what the audio sounded like__ with a narrow CW filter (awesome, right?), and a 3KHz wide USB configuration. I think this should be more than enough to carry us through a mission, and aid in direction finding of a landed payload!

__Notes about filtering:__ The output of this transmitter is quite harmonic-rich. The oscillator produces square waves for goodness' sake! The class C amplifier smooths a bit of that out, but you still need some low-pass filtering, not shown on the schematic. I think for my purposes a 3-pole [Chebyshev filter](http://en.wikipedia.org/wiki/Chebyshev_filter) will suffice, but just keep this in mind in case you replicate my design. You certainly don't want to be transmitting out of band! Below is the output of the transmitter viewed on my scope. It's suspiciously smooth, which leads me to wonder about the accuracy of my scope! I really should get a spectrum analyzer.

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[![](DSCN1707_thumb.jpg)](DSCN1707.jpg)

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