Sunday, September 15, 2019

Virginia to New Hampshire (one way) on 8 Parts and 20 mW


Having gotten the regen receiver portion of the ET-1 transceiver working nicely, I'm now working on the transmitter.  This is a much easier circuit to get going. (Check out the right hand side of the schematic below --- that is the transmitter.)  I have not made any contacts yet, but yesterday I called CQ on 7050 kHz and watched the Reverse Beacon Network to see if any of the skimmer stations picked me up.  Success!   W3UA up in New Hampshire received my signals. 

I was running about 30 milliwatts to my doublet antenna. The transmitter consists of EIGHT parts.  And three of them are the low pass filter. 

Next step:   Bring the transmitter and receiver together by using the switching scheme that OM Yingling used.  The RX and TX will share the same single FET (MPF-102 or J-310) with all three leads from the FET switched from TX to RX.   Then I will try for the elusive QSO with a single FET. 

More ET-1 related posts here: https://soldersmoke.blogspot.com/search?q=ET-1





3 comments:

  1. Put a relay (4PDT - using 3 poles) in place of the switch and you can get full QSK! Bruce - KK0S

    ReplyDelete
  2. Been watching this minimalist adventure. Amazing what just a few parts can do. N0WVA

    ReplyDelete
  3. I'm glad my skimmer could pick you up... it's antenna is directional (beaming NE) on higher bands, but on 40 it's effectively stacked dipoles (at 40 and 80 feet) -- so it was receiving your signal from the SW. Considering power factor 50,000 vs Legal limit (47 dB), if you were full power, your S/N should be 54 dB. You got a pretty good antenna!
    73 Gene W3UA

    ReplyDelete