IFR Com120b errors

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jeryray
New User
Posts: 19
Joined: Thu Jan 10, 2019 7:11 pm
What radios do you own?: Many ICom, have 4 Mototrbo rep

IFR Com120b errors

Post by jeryray »

I have Com120b with Distortion meter and RX level errors.
Does this sound like caps on the baseband unit?
What else has caused these failures.
jry
Posts: 448
Joined: Fri Feb 06, 2004 3:14 pm

Re: IFR Com120b errors

Post by jry »

there are a number of boards on the COM-120 subject to cap failures ...the baseband card just has a lot more of them than the others.

i goes beyond just replacing caps ... you often have to remove and clean components ( op amps , resistors and capacitors ) and clean the PCB. If you wait too long you can have open traces from the corrosion as well.
Just repairing the baseband card can be an all day affair and often need an extender setup to troubleshoot.

The unit will have to be re-calibrated after repairs as well and both of those errors can come from the adjustments being out along with broken HW.

Usually I pull all of the cards and front panel and inspect for bad caps and leakage damage.

The keyboard is usually cleaned and repaired especially on the B and C version ( "A" version keyboard was better ...another example of newer is not often better....just cheaper to make )

Fans usually hit the can as well as the battery based components on the processor.
CircleBat
Posts: 171
Joined: Mon Oct 08, 2007 3:11 pm

Re: IFR Com120b errors

Post by CircleBat »

jry.. I have an ifr1600 with the same problem... cleaned all the cold solder joints up and connector and still does the same problem.. is there a specific spot where i can change out certain caps? greatly appreciate your help if you could point me in the right direction as there are no service manuals for this machine

CircleBat
jry
Posts: 448
Joined: Fri Feb 06, 2004 3:14 pm

Re: IFR Com120b errors

Post by jry »

1600's leverage some of the same engineering but for the most part did not have the amount capacitor failures as the COM-120.

Not sure which test is failing on the 1600 but usually there are HW failures and alignments to correct the issues.

The 1600 is bigger and heavier but usually more reliable than the 120's
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