Hi,
Thank you for posting the pictures.
If I had to guess the schematic, I would guess this:
If you still have the unit open, may be you can confirm the component values?
Make sure that you protect your spectrum analyzer input, preferably a dc block and a limiter or as a minimum a high power 10dB attenuator.
Regards,
Jay_Diddy_B
Good guess:
- the 4uF's are actually 5uF
- the 1k is actually 1k1, (only one) and is connected from the BNC out to chassis
- there is a 560k in parallel with the 5uF capacitors
- There is a 51r in the switch circuit
Good advive, I will use a DC block and attenuator, or perhaps add one internally to be on the safe side.