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SATOLEX · 16th Mar 2021, 11:15 pm

I have measured the mixer separately and it worked fine. It has a conversion loss of about 8 dB if I apply a 800 MHz signal to the RF input. I have also remeasured the IF1 and observed the same interconnection issue. Outside the analyser it was working fine. I have opened the mixer to see what the condition is. It has the same issue as the mixer of Matt, lead rot. What do you think, do not touch it and wait until it falls of or clean it? I saw a note on the cover that the diode was replaced in 1989. It would be wise to buy a spare diode but what Jeremy mentioned is that it is hard to get one. The 39 Ohm series resistance looks strange, what do you think?

Regards, Lex

16th Mar 2021, 11:15 pm	#126
SATOLEX Triode Join Date: Feb 2021 Location: Leiden, Zuid-Holland, The Netherlands Posts: 26	Re: Spectrum Analyser TR4172 I have measured the mixer separately and it worked fine. It has a conversion loss of about 8 dB if I apply a 800 MHz signal to the RF input. I have also remeasured the IF1 and observed the same interconnection issue. Outside the analyser it was working fine. I have opened the mixer to see what the condition is. It has the same issue as the mixer of Matt, lead rot. What do you think, do not touch it and wait until it falls of or clean it? I saw a note on the cover that the diode was replaced in 1989. It would be wise to buy a spare diode but what Jeremy mentioned is that it is hard to get one. The 39 Ohm series resistance looks strange, what do you think? Regards, Lex Attached Thumbnails