The wattmeter circuit is pretty simple. There's not much that can fail. It is essentially the same as a W4. Put your meter on the FWD wattmeter and see if voltage goes up when you transmit power. If you see a sensible increase in voltage suspect the FWD/REF pushbutton or associated wiring. If you don't, meter the high side of pot R2001 on the back side of the Low Pass filter module and do the same. If you don't see voltage check the diodes in the meter circuit (CR2001 and 2002). If the diodes are good check that your transmit output is where it is supposed to be, not oscillating out of band and being absorbed by the low pass filter. You may also have a band switch, T/R relay, or low pass filter issue.
The RS cleaner should be OK, but you will want to take precautions to ensure it doesn't spray everywhere.
73
-Jim
NU0C
On Mon, 12 Feb 2024 11:07:19 -0800
"Bill NZ0T" <nz0tham@...> wrote:
[Edited Message Follows]
Hi Jim,
I really appreciate your help.? I was loking at the wrong PDF and the ALC board pic was so blurry I didn't see the label.? I was able to get the voltage down to around 0.5 VDC on a multimeter.? I don't have a VTVM but I'm pretty sure these new meters work OK for this.? The AC control on the ALC board is still extremely touchy and the Forward/Reflected power adjustments do nothing.? In both Forward and Reflected as selected by the pushbotton the panel the meter actually goes below zero.? I was able to get the S-meter set so I know the meter is OK.
So as far as I can tell the ALC is still not working properly.? Still think that control could be the problem.? I do have a can of the old Radio Shack control/contact cleaner and lubricant - wopuld that be OK to use on that control?
73, Bill NZ0T
--
73
-Jim
NU0C
Jim Shorney