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Radio Make and Model: President Lincoln (HR2510) Year model 1988
PCB Number: Main board PB-111AB
PLL Number: PCB PB 121 AC HCT 58 NY 94V-0
Test gear available: F-Counter C57
Symptoms: Off Freq, on USB RIT is standing on 9 clock

What is working: Tx Am/Fm/Lsb/Usb/Cw Rx Am/Fm/Cw/Lsb Usb off freq,

What has been tried:Tried to adjust the Pll-board Tp 304 unstable 32,31000 to 32,65000 Mhz Tp 306 unstable 11,33900 to 11,62400 Mhz Tp 303 6,5 volt adjusted from 3,08 volt.
Tp 1 Cw ok in freq been able to adjust,
Lsb ok in freq been able to adjust, Usb not ok in freq not able to adjust freq fixed on 10,69405 Mhz nothing happens when I try to adjust L116

Did it suddenly happen ?: It have been stored for 10 years and It was working then.
Anything else that may be of help?: I did a misstake I shorten one off the MC301 so now Its only have one on D102 no D101.

Regards Per Andersson
PRESIDENT LINCOLN

All of these units, (including the HR2510) have problems when they get older, what you need to start out with is to replace ALL of the electrolytic capacitors on the MPU PCB, there is only one which you do not replace, the large one that is next to the MPU, as it is a special memory backup capacitor.

That may well fix the frequency issue, it likely will fix the instability in your readings, if not then there are a couple more parts that may need to be replaced.

I have now change all the caps and mcu/cpu
But it´s still fixed on 10,69405 Mhz nothing happens when I try to adjust L116 so I tried to change L116 and now I can adjust the freq but not adjust it higher than 10,69405 only lower and the L116 it´s taken from a radio that works (President lincoln) .
Q106 checked ok,D141 checked ok,C66 checked ok,L100 checked ok.
Lsb and Cw are ok in freq at tp1.

Cheers

Per Andersson