Quick Login

Author Topic: New Homebrew Transceiver at VE3LYX  (Read 1130 times)

Offline ve3lyx

  • Commodore
  • *
  • Posts: 159
  • Country: ca
New Homebrew Transceiver at VE3LYX
« on: June 13, 2016, 20:20:00 UTC »
I always had a curiosity about the Weskit BN-1 Transmitters from the 1950s. Recently I was given a schematic and while I didn't build a clone  what I did build was certainly influenced by the schematic.
I used a ECC832 (12dw7) instead of a 3a5 dual triode The ECC832 is a dissimilar dual triode. One side being like a 12ax7 and one like a 12au7. This gives the light side for a good regen and the power side for a power osc.  I built it as a VFO instead of a crystal osc as the Weskit was and I tuned both TX and RX wit a dual gang variable cap, using a bandspread on the regen side and a padding cap on the TX side to keep things in reach. Both circuits are based on a standard Hartley oscillator, my personal favourite. After initial fire up I added a 12aq5 simple audio amp. Despite the light parts count it works quite well. The RX can hear everything my digital Rx can and sometimes a wee bit better. The two sections track well and the station can be found if off a bit my a minor tweak on the bandspread. The TX puts out a reasonable amount for a QRP rig and is set up to operate on 40M. It has been a pleasant surprise and I find my self spending hours playing with it.
I am hanging around 7040 khz when possible and when the band is open looking for contacts.  Power out seems to be in the neighbourhood of 2 and a half watts.
donVe3LYX

Offline GM0LVI

  • Admiral
  • *
  • Posts: 393
  • Country: scotland
Re: New Homebrew Transceiver at VE3LYX
« Reply #1 on: June 13, 2016, 21:28:36 UTC »
Well done Don. Nothing like a rig that glows!
Dave

Offline ve3lyx

  • Commodore
  • *
  • Posts: 159
  • Country: ca
Re: New Homebrew Transceiver at VE3LYX
« Reply #2 on: August 02, 2016, 12:02:20 UTC »
After getting sidetracked by the build of the German style Spy Adapter Set Transmitter I pulled the transceiver mentioned here back off the shelf and spent last night testing and using it. The receiver in particular despite its simplicity does a good job of hearing even very weak stations. I bought an NOS J-38 CW key with a shorting bar as none of my many keys have a shorting bar on them. I needed it because on RX I need to close the B- circuit which is normally open with Key up on TX. The shorting bar does it nicely. The regular Rx TX switch is simply a DPDT and didn't have enough contacts for the job. This addition completes it satisfactorily. I think I will operate it for a few days just for fun so if you hear me squeaking on or around 7048 to 7054khz  feel free to jump in. It has been a pleasure this project. I am surprised by its performance. Time to just enjoy it.
donVe3LYX