This is a really long shot.
I am looking for a user manual and more importantly, a schematic for a "Agikawa APM-1H" automatic SWR and peak reading power meter, 1-8 ~ 60MHz.
One is pictured here.
It looks exactly the same as the Macaw PRM-1, for which I have the manual and schemnatic but the active circuitry inside is completely different.
Searches via Google and BAMA have drawn a blank, so I'm hoping somebody might have owned one in the past and still knows where to find the documentation.
I have changed the 2 ICs and 4 transistors. All the diodes check out fine as well but the fault persists. When switched to "PEP", the meter pins on 200W scale and shows around 400W on the 1000W and 2000W scales, without anything being connected to the device.
I would really appreciated any leads, so I can repair it and pass it on to a friend who is getting back into the hobby after many years away.
Thanks and 73, Alek VK6APK.