Here's an update on my BITX 60 project. The modified module is in the lower box. An Arduino Uno and an Si5351 (this one with unreleased smoke) is in the Heath QF-1 box on the top. I am using an Arduino sketch written by Don ND6T. It spits out the needed 17 MHz LO freq needed for each of the five 60 meter channels. You can scroll through the channels by just holding down the rotary switch interrupt button.
There is a move afoot to liberate from channelization about 15 kHz of the 60 meter band. When that happens, I'm ready to go -- I'll just reconnect the rotary encoder for the Si5351 and load some new code. I suspect that by the time that happens, Don will have modified his code so that the 15kHz "tunable" segment will be integrated into the current program and will appear as one of the options as you scroll through the choices.
For reasons that most readers will understand, I have resisted channelization for many years. But here I am, channelized on 60. It is not so bad. I'm having fun listening to a new band, using a modified BITX, an Arduino, a bit of Heathkit and code from a fellow ham.
Inspired by Don ND6T, I decided to put a BITX40 Module on the 60 Meter band. All you really have to do is modify the bandpass filter. Don showed us how to do this by simply adding three 100pf caps. I was going to order SMD caps, but this just didn't seem right -- I found three of the old "with wires" kind and easily soldered them into position. The bandpass shifted as Don had promised.
You also have to change the VFO freq. You need it to be in the 17.3 MHz range. Don has a nifty program for the Raduino that also works with the Si5351/Ardunio Uno combo that I use. It keeps you on the five channels currently authorized on 60. Unfortunately I managed to let the smoke out of yet another innocent Si5351 breakout board. Amazon and Lady Ada are sending me another one, but in the meantime I pressed into service an old AD9850 DDS. I had a little trouble getting the 17MHz signal through the BITX's VFO 4 MHz VFO system, but I eventually figured it out. (More on this later.)
The receiver is working nicely. I like the relaxed 60 meter conversations.
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