Need Com 120A help .....

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Darel
New User
Posts: 10
Joined: Tue Jan 03, 2017 7:19 pm

Need Com 120A help .....

Post by Darel »

Hello all ...

I was recently given a IFR Com 120A that seems to be in very nice shape but the power button up front will not turn the unit on or off ( I need to use the rear switch ). Also, after the self test it gives the message "rf term overheat, reduce rf input" although I have no rf going into it. If I hold the front power button down while I turn on the unit from the rear I can get it going and it seems to work ok but if the front power button is pressed it will freeze up.

Has anyone else had a similar problem with one ...looking for some guidance!

Thanks,

Darrell
lc4600
New User
Posts: 16
Joined: Mon Aug 03, 2009 7:29 am

Re: Need Com 120A help .....

Post by lc4600 »

The metallized plastic switch has lost its ability to go low enough to toggle the on/off circuit in the power supply.
IFR just replaced the overlay to repair this.

Base Band PCBD needs washed and all the surface mount electrolyte capacitors replaced.
What am I saying- all the surface mount electrolyte capacitors replaced on all the PCBDs.
I use multilayer ceramics instead -rocks don’t leak
Carl N0PXJ
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