The personal website of Scott W Harden

Impeded Progress

Spring break is over and dental school classes have resumed. An unexpected side-effect of spending all of spring break working so hard on my QRSS VD software project is that when I resumed dental school, I actually feel more relaxed. It’s like spring break was my period of intense work, and the rest of dental school is my “break”. It makes me a little disappointed though - I feel like dental school isn’t pushing me very hard, and I don’t feel like I’m learning or growing like I could be. With the estimated cost of tuition totaling ~$200,000 for four years of dental school, I’d have expected classes to feel a little less trite. Anyhow, it is what it is, and I’ll make the best of it.

I’m spending the weekend polishing-up code and reading circuit diagrams. I have a few projects on my plate (involving QRSS in some way or another) and I’m managing the transition from productivity back to dental school the best I can…

W4DFU Gator Seen in Canada

I don’t have long, but the picture speaks for itself. Sent from Florida to Canada. I used VE1VDM’s “Big Ears Grabber” in Canada.

QRSS VD version 1.04 Released

I’m proud to announce the first public version of QRSS VD has been released!

Edit: QRSS VD is now on GitHub: https://github.com/swharden/QRSS-VD

How to Destroy a Radio Operator

After priding myself on my ingenuity a few weeks ago for documenting my homemade stealth indoor apartment antenna for 40m and 20m, it seems that the green movement has contrived a plan to cripple my successes. So far I’ve made a few dozen contacts in Morse code with my humble little setup (~20 watts of power, direct conversion receiver, indoor homemade antenna). The photo shows some QSL cards I’ve gotten. Anyhow, my apartment manager decided that my apartment needed to have solar panels added to it. It’s too early to tell for sure, but spinning the dial a few times and hearing *nothing* makes me think that it dramatically impacted my reception (and likely transmission) in a dramatic way.

There are the QSL cards I got so far:

I think the AJ4VD station has been effectively shut down!

Overseas QRP Transmission

While working on the spectrograph software I’m trying to complete this spring break, I happened to capture a cool signal from Italy. IW4DXW was sending some cool signals that I captured around 10.140 MHz. See how his call sign is written “visually” on the spectrogram? I thought I’d post it because it’s an encouraging sign that my software is going in the right direction. Also note the numerous QRSS FSK signals around it! So cool.

__I sent an email to the operator and he responded __with station information:

Hi Scott! Thank you so much for nice report. This is a short description of my homebrew beacon. The audio source is a normal MP3/WAV player. The file (.WAV) of my hell message (8x8 char) is generated using Chirphel (program by DF6NM) with a fmax~=800Hz and BW=5Hz, and processed with Csound to obtain the phase relation R = L + 90° between channels (hilbert function). A 10.140MHz oven xtal oscillator (adjusted for +880Hz) is a PLL reference used to obtain a x4 frequency. This clock with the 2 audio channels are applied to a “Softrock style” SSB phasing modulator (double H-mixer with 74HC4053 ic).

The LSB output signal (10.140,080MHz @ ~ -3dBm) is amplified by a 2N2222 (driver stage) and a 2SC2314 (linear PA stage ~1W P.E.P. max, but 100 – 200 mW of average power). I’m using a 30m dipole (inverted vee @ about 50 feet). 30 meters looks good today! My signal heard in VK2 too…

Greetings from north Italy, dear Scott!

Riccardo, IW4DXW

__200mW? That’s awesome! __Maybe one day I’ll build something cool like that! I will now return to the programming project that has been eating-up my spring break.

Here’s a screenshot of what I’m doing now I’ll keep for the future memory of this break. Yes, I’m on a Windows machine. I’m at the W4DFU radio club station (they have nicer computers than I do!)