Well, FYBO was a total bust for me. I setup in the backyard with a 40m EFHW, HB1B, J38 and the Android keyer. The temperature was about 20 degrees and breezy. I found that I was getting much colder than I expected. Initially I had a hard time finding an open frequency to call CQ since there were so many other contests going this weekend. The contest ops were sending way faster than I could copy, so I had no chance of working any of them. I managed to work 1 FYBO station - Nick WA5BDU. (I recognized the callsign from the QRP-L)
Anyway, I gave up after about 45 minutes because I started picking terrible EMI from somewhere and could hardly pick out anyone. I normally have an S7 noise floor in my house, but outside is mostly quiet... Of course not this time.
The Android keyer worked well, but I realized that it might have been best to use a 10 turn pot instead of a fixed value resistor, because as the circuit got cold, the frequency shifted some. As a result, I had to adjust the sidetone on the Android app to find the LM567's frequency. Also, I should consider some RFI mitigation because unless I kept the keyer away from the feedline, the circuit was a bit sporatic.
Oh well. Maybe someday I'll move somewhere with more property and ZERO neighbors to cause EMI.
Sunday, February 5, 2017
Friday, February 3, 2017
Homebrew Android based keyer
Every year the QRP group Arizona ScQRPions host a field day contest called FYBO (Freeze Your Butt Off). The premise is like any other radio contest except it takes place out doors in the cold, and your score multiplier is based on the lowest temperature at your operating position.
This will be my first CW contest that I'll participate in. I only use a straight key, and for sure don't want to send CQ FYBO DE AB9LM for the duration of the contest.
Rather than programming a micro controller with my message, I decided to use an already existing device that can hold any number of messages, has a thermometer, browser, and clock: My Android device.
From the App store, I downloaded Androidomatic Keyer to handle the generation of code. To actually key my radio, I built an LM567 tone decoder circuit "hard coded" for 1khz. I've been sitting on a package of 10 of these things and haven't yet come up with a use for them. This seemed like a great application.
I followed the schematic from http://www.m0tgn.com/2015/07/cw-decoder-electronics.html
to get me in the general ball park. Getting the frequency set was a real pain using a trimmer, so I opted to use a 4.7k resistor instead. Using the formula 1/(4.7k X .22uF) put me pretty close to 1khz.
There is a bit of a sweet spot for setting the frequency and the volume level, but once found, it doesn't miss a beat.
I even plugged the input to the audio out of my TS-830 and it kept up fine with the speed demons on 14.015
The video below is a demonstration of the interface at work.
Using this circuit, I may see if I can make a CW decoder for the pizero.
Hopefully the propagation Gods smile on me tomorrow, or at least hope my CW isn't too rusty.
This will be my first CW contest that I'll participate in. I only use a straight key, and for sure don't want to send CQ FYBO DE AB9LM for the duration of the contest.
Rather than programming a micro controller with my message, I decided to use an already existing device that can hold any number of messages, has a thermometer, browser, and clock: My Android device.
From the App store, I downloaded Androidomatic Keyer to handle the generation of code. To actually key my radio, I built an LM567 tone decoder circuit "hard coded" for 1khz. I've been sitting on a package of 10 of these things and haven't yet come up with a use for them. This seemed like a great application.
I followed the schematic from http://www.m0tgn.com/2015/07/cw-decoder-electronics.htmlto get me in the general ball park. Getting the frequency set was a real pain using a trimmer, so I opted to use a 4.7k resistor instead. Using the formula 1/(4.7k X .22uF) put me pretty close to 1khz.
There is a bit of a sweet spot for setting the frequency and the volume level, but once found, it doesn't miss a beat.
I even plugged the input to the audio out of my TS-830 and it kept up fine with the speed demons on 14.015
The video below is a demonstration of the interface at work.
Using this circuit, I may see if I can make a CW decoder for the pizero.
Hopefully the propagation Gods smile on me tomorrow, or at least hope my CW isn't too rusty.
Thursday, February 2, 2017
TS-830s -- Fixed!
The new capacitors arrived today. Of course I forgot to take a picture of the caps or of the installation... But I'm very pleased to say that this is exactly what the issue was.
After soldering in the new capacitors, bypass cap, and bleeder resistor, the output peaks 100 watts and HV is back up to 800v like it should be.
Wow... I finally fixed something.
After soldering in the new capacitors, bypass cap, and bleeder resistor, the output peaks 100 watts and HV is back up to 800v like it should be.
Wow... I finally fixed something.
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