Theres a youtube video out there of a tech locating a bad Pin Diode, CR104 on the output PCA section in the SM, Pg 8-17 for the famous "Uncal" issue when using the lower frequencies the instrument can generate.
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He borrowed a Pin diode from another part of the board CR205-CR208 saying these in parallel were overkill and got the error cleared.My copy of the schematics for CR104 are bad so I cant see the actual PN but the other ones are MA-4P532.
Web search no longer yields that as a valid part but there are more in the series number available.
Any ideas on what would be a good sub for this Pin diode?