On 3 Apr 2024, at 18:58, shaider.msee20seecs via groups.io <shaider.msee20seecs@...> wrote:

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Hi All,

Thank you for adding me to the group. I have HP 8510C which is given me “Caution: No IF found” and when it tries to measure higher frequency (say above 5 GHz) then the signal gets acquisition becomes slow and distorted.?

From a service manual i saw that it occurs when power is very low about -20dB but in my case i had set to -5dBm. I tried increasing the power but all in vain.?

I suspected that there might be issue with source. It comes with 8360 swept series synthesiser which i have one going upto 20GHz and other going upto 50 GHz.?

I connected spectrum analyzer at the output of the source synthesizer (50GHz option) and saw really less power of about -39dBm @5GHz with a 10db attenuator.

I did the same steps with source synthesizer (20GHz option) but saw a higher power at @5GHz. Thus, i knew something was wrong with source synth (50GHz option).

After that, i disassembled the source top panel to see if i can detect a faulty connection/ component. I noticed the last component in the chain is a component named 5086-7603. I believe its an amplifier that also provides power levelling (need anyone of you to confirm that).?

I then proceeded to disconnect the input of this component and connected it directly to spectrum analyser and saw power was -34dbm which was 5dbm better than what i measured before (39dbm).?

I have so far established that this component might be faulty. I would like to know from your experience if you can guide me further on this with any suggestions. Share any block diagram of the swept series synthesiser.?

Any suggestions to fix this issue are most welcome.

Thanks

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