I have a Macaw PRM-1 peak reading power/swr meter. From looking
through the archives on this list, I see that others have been
looking for manuals or schematics for this meter.
It seems that this unit has a commonly occurring fault. Namely, when
set to peak reading mode, the meter moves hard over to the full scale
position. Mine had the same symptoms.
There are two active devices in the meter. A 2SK117 mosfet and a 741
op amp. To clear the full scale fault, you simply need to change both
devices. I just did it with my unit and I'm very pleased to have the
meter working as it should. You don't need the schematic.
73, Alek
VK6APK
PS: I have 9 spare 2SK117's. If anyone else has the same problem, let
me know and I'll post one to you.
http://www.qrz.com/db/vk6apk
http://www.qrz.com/db/vk6ap
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