01 December 2011

TX-only transverter for 4m

While I have no news about a possible 4m allocation for Italy in the next months, I have started working on my TX-only transverter - a "txverter"? - for HF-to-70 MHz.

The idea behind this project is that the IC706MKiiG receives on 4m, so there is no need for a full transverter, provided the operator accepts to operate split. It is a KISSAL principle: Keep It Short Simple And Lazy :-)

I decided to replicate G3XBM's simple transverter, TX chain only. I will build it manhattan/dead-bug style using an ADE-1 passive DBM mixer.

The picture shows first components placed on the copper clad board:
  • 5V voltage regulator
  • canned oscillator @44.900 MHz
  • HF input attenuator of about 30dB (50, 680, 100 ohms)
Current drain at 12V is about 18mA, all for the voltage regulator and the canned oscillator.

The output of the latter is not a sine wave on a 100 MHz scope&probe, but it swings 0-5V if left floating.

I plan to blog how the circuit grows and how it performs.