7A18/Repairs: Difference between revisions
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==Variable gain pots== | ==Variable gain pots== | ||
These pots (R237A,B and R437A,B 315-0241-00) are bonded together - that bond can break which stops the gain push from working. Looking at a few 7A18s, I see that the design was changed at least once. | These pots (R237A,B and R437A,B 315-0241-00) are bonded together - that bond can break which stops the variable gain push toggle from working. Looking at a few 7A18s, I see that the design was changed at least once - some revisions don't use epoxy. | ||
[[Category:Instrument repair reports]] | [[Category:Instrument repair reports]] | ||
Latest revision as of 07:14, 20 July 2024
Attenuator solder joints
The pins of the attenuator modules are connected to conductive traces on the ceramic substrate inside by low-temperature soldering, which can go bad. Re-seating the module can temporarily restore the internal contact but will usually not fix the problem permanently. Repair is possible by opening the click-locked lid and carefully resoldering.
Variable gain pots
These pots (R237A,B and R437A,B 315-0241-00) are bonded together - that bond can break which stops the variable gain push toggle from working. Looking at a few 7A18s, I see that the design was changed at least once - some revisions don't use epoxy.