Rohde & Schwarz CMU200 CMU-B95 ADDITIONAL RF GENERATOR removal?

[Ringmodulator]

Hi,

for my understanding, the CMU-B95 ADDITIONAL RF GENERATOR limits the max RF input to 2W.

 Is it sufficient to remove this unit, to be able to use the full RF input of 50W, or do I need some kind of "jumper cable" to bridge the connections of the removed board?

Chris

[Ringmodulator]

My further investigation turned out, that the B95 is mounted directly to the RF frontend module and replaces the heatsink with air channels and fan of the standard frontend module.

So simply removing the B 95 module will not work, as the heatsink with the fan will still be missing.

If someone has a defective unit, I would be interestef in the heatsink and fan. Please feel free to contact me.

[RF_fanatic]

You would need a different frontend

I do not have my data here but I think you need a 1100.3120.02 module and probably now have a 1100.3120.04 or similar

I can check if you want when I'm back in the hobby lab.

[CJay]

Interesting, so is the front end different inside or is it just the lack of heatsink and fan that limits it to 2W...

I have both types, if I get a day spare I might investigate.

[sparkchaser98]

I'm curious about this issue too! I just purchased a CMU200 online and it has a sticker saying 2W on the front as well! I haven't actually received the unit yet so I can't see what options it has yet. But I need to be able to measure 40 watt VHF mobile radios, and I was hoping to do so without worries of needing an additional attenuator or such. So, if there were a simple mod to handle 50 watts that would be great! But what would the tradeoffs be?

[oh2ftu]

Just use a suitable pad. It can be preprogrammed into the CMU (Attenuation values per frequency).
Even Motorola recommends using a 20dB pad while tuning their radios. Just in case.

[Ringmodulator]

Thank you for all the responses.

Just use a suitable pad. It can be preprogrammed into the CMU (Attenuation values per frequency).
Even Motorola recommends using a 20dB pad while tuning their radios. Just in case.

Yes, that was also my thought and I am awaiting the delivery of a 20dB/50W attenuator.