More Techie bits.

The parts used so far and the prices:

  1. CM108 USB Sound card,       £2.32
  2. CH340G USB-Serial Bridge  £0.74
  3. 1:1 Audio transformers, 2 of  £0.29 each.
  4. PC817 Optocoupler                £0.02 Yes, 2 whole pennies each, this part controls TX.
  5. 3.5mm Jack Plug                    £0.49 For the CI-V port on the radio
  6. USB Hub                                £2.30 Not as expensive as I thought it was
  7. 13 Pin DIN Plug                     £3.79 The most expensive bit, the Icom Accessory socket plug.
  8. Proto board                             £0.30 Absolute bargain, great quality and through hole plated too.


Cables were from the junk box and the resistor (there is one) a penny?

So, total price to buy all the bits (and you may not need the USB hub if your PC is well endowed)

£10.54.

There's still the Isolated CI-V interface and I will probably need to attenuate the audio coming into the sound card as I've had to take the record level *all* the way down and WSJT-X is still reporting it a little high but I think we're going to be on the right side of £13 total cost for all the bits.

I'll be recycling a case from an old external hard disk and I'll tidy up all the cables as well but I'm very satisfied with this work in progress.

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