Ramsey HR-1 40 meter DC receiver
I've mentioned the Ramsey before:
https://wb9kzy.blogspot.com/2022/02/including-ic-sockets-with-kits.html
Any time I wanted to try the Ramsey out it meant also getting out the DDS VFO and then hooking them together. So I thought why not revert the Ramsey back to the original Varactor based VFO.
Since I had just unsoldered 1 leg on 4 different parts (C2, C3, D1 and R5):
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It was easy to unsolder the RCA jack for the DDS VFO and resolder those 4 parts. I left the other mods in place. A 7808 8 volt regulator was used in place of D2. Also a cap was added across the feedback resistor to reduce hiss. BTW, the HR-1 differs from the schematic - it has an 8 pin dual op-amp instead of the LM386 amplifier shown. Not sure where the manual and schematic are for the HR-1. Also, I added an LM386 audio amplifier on the bottom of the chassis.
Then I tried it out and realized why I had added the DDS VFO input to begin with. The receiver was drifty, hard to tune due to the lack of bandspread and simply would not tune below 7280 kHz no matter what I tried.
Probably the Ramsey should be ditched and some different receiver put on the chassis (from an old Conrac video monitor) - we'll see.
Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm
https://wb9kzy.blogspot.com/2022/02/including-ic-sockets-with-kits.html
Any time I wanted to try the Ramsey out it meant also getting out the DDS VFO and then hooking them together. So I thought why not revert the Ramsey back to the original Varactor based VFO.
Since I had just unsoldered 1 leg on 4 different parts (C2, C3, D1 and R5):
Then I tried it out and realized why I had added the DDS VFO input to begin with. The receiver was drifty, hard to tune due to the lack of bandspread and simply would not tune below 7280 kHz no matter what I tried.
Probably the Ramsey should be ditched and some different receiver put on the chassis (from an old Conrac video monitor) - we'll see.
Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm
