[Amps] Macaw PRM-1

[Alek Petkovic]

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