LK-800 Amp Supply/International input tune caps

[Radio Tech]

I have a LK-800 in the shack. The ceramic tune caps on the 10 meter & 15 meter input tune board are shorted. Most likely from excessive drive levels.

The four capacitors (2 per band) have no numbers on them that can be read. Looks as if they were sanded off.
On the schematic they are listed as 10/15 meter input capacitors. No part numbers or values noted on schematic.

Anyone know what the values are or at least the part numbers?

This is the Amp International version. NTC
Only 10 and 15 are out. Rest of the bands work well.

I am thinking they may be around 300pf but want to be sure.

Thanks

 

[paws264]

I have a LK-800 in the shack. The ceramic tune caps on the 10 meter & 15 meter input tune board are shorted. Most likely from excessive drive levels.

The four capacitors (2 per band) have no numbers on them that can be read. Looks as if they were sanded off.
On the schematic they are listed as 10/15 meter input capacitors. No part numbers or values noted on schematic.

Anyone know what the values are or at least the part numbers?

This is the Amp International version. NTC
Only 10 and 15 are out. Rest of the bands work well.

I am thinking they may be around 300pf but want to be sure.

Thanks

Disconnect the trimmers from the circuit, visually inspect the device by removing the screw and counting the mica / metal plates; go to your junk box and match it up with one you find.

If you have to crank the trimmer too tight for max output/minimum SWR then, you need a larger value while, if your compression trimmer is loose, you need a smaller value.

.

 

[Radio Tech]

Disconnect the trimmers from the circuit, visually inspect the device by removing the screw and counting the mica / metal plates; go to your junk box and match it up with one you find.

If you have to crank the trimmer too tight for max output/minimum SWR then, you need a larger value while, if your compression trimmer is loose, you need a smaller value.

.

I did find the part numbers. The part number for the compression mica trimmer is GMA 30600 and measure from 160
pf to 230 pf.

I have already done what you suggested but was going to see if I could find originals. I think I am going to upgrade it to a bigger package and do away with the smaller trimmers. I just dont want to make it to strong so the owner want damage something other than the trimmers.