I had two problems with my brand new Kuhne MKU 23 G4 transverter.  Both were my fault.  I blew the PTT input protection diode, so that needs replacing.  I’ve removed the original and at the moment I’m using an external diode.  Second issue is that I can’t get enough output when driving it with my DDK Anglian 2m transverter, so I need to change the input pad resistors. As I have already invalidated the warranty, I might as well go ahead.

Anyway, here is what it looks like inside.  Note the missing diode…

Nicely CNC milled cover

You *can* see that missing diode, can’t you?

OK, here’s a clue. It is near to the 16 other diodes at the top left, near the Atmel CPU.

To fix the second issue, I need to change two 1.2k resistors next to the relay and TX level pot.

Just hope I have something suitable in the junk box.  I found a 39R 1206 in there and used it to increase the gain of my Kuhne 3cm transverter kit just now, so I can get full power out of that now. For reference, the coding on SMD resistors is here :  http://www.resistorguide.com/resistor-smd-code/

Finally, a gratuitous shot of the PA stage and input amplifier