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June 11, 2024. Revisiting the Design Process

As result of time constraints and not building any new hardware, I am forced to look back at stuff I have built in the past. Given the sheer numbers of SSB Transceivers built, there is no question I am in need of some serious psychotherapy.

I am having a difficult time internalizing the amount of hardware that is in storage boxes. I think I could operate a different transceiver (both commercial and homebrew) every day for a two month period without using the same rig twice. That is a definite sign of a serious illness. 

One factor has emerged and discounting the KWM-4 all the homebrew stuff is pretty bare bones and not complex. The P3ST uses only 7 Transistors

The use of the same modules in both Receive and Transmit cuts way down on the number of circuits. What is cool is that many of the circuits use a different form of topology and devices. Read they are not simply a warmed over Bitx with a new front panel.


  1. The Plessey circuit with the cool bilateral 2N3906/2N3904
  2. The Steered IF module with two NE602's
  3. The Dual J310 configured as a DGM Module
  4.  The 2N2222A Steered Module
  5. The BFR106 Steered Module
  6.  The MC1496 Modules 
  7. The MMIC Bilateral Module
  8. Dual Filter with fixed BFO
  9. Finally, an actual TIA Based Transceiver

As I ponder over the list and the fact there are so many approaches, gives rise to the question does one stand out? My answer is that some have features that are more useful than others. Read the TIA and Bitx approach does not sit at the top of the list!
 
I think also that when you only build with the TIA topology or Bitx you miss out on capabilities of some of the devices like the BFR106, Dual J310 and the MMIC's.


Lower Board of The Simpleceiver 40M SSB XCVR
 
In a 4X6 area, starting on the right, we have the Band Pass Filter, ADE-1 Tx RX Mixer, the IF Module (steered) with the J310s configured as a DGM, the Product Detector & Balanced Modulator (ADE-1),  the Mic amp and in the lower center the Audio Amp.
 
 
Top View


The above photo is of the the top board of the two Board transceiver. In the lower left is the steerable Rx RF Amp / Tx Pre-Driver using the Dual J310 and to the right of that is the two transistor amp circuit from EMRFD where the final version has the BD139 versus the 2N3866. In the upper right hand corner is the IRF510. Not seen is the underside aluminum plate that is 3 X3.5 inches -- the heat sink for the IRF510. In the upper left is a blank space for the Arduino Nano and Si5351.

Listen to how this radio sounds as you ponder a purchase of a Xiegu G106C.

Simpleceiver 40M SSB


WYKSYCDS!
 
73's
Pete N6QW


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