Repairing a poorly radio receiver

My friend Brian M6BOH inherited a JRC NRD-525 receiver which at first glance seemed in good condition.

JRD-525 Receiver
JRD-525 on the bench for some TLC

However, it soon became clear that all was not well. The set could be tuned with the large tuning knob, but several keys on the number pad would not work. Closer inspection revealed that the set had met up with a cup of coffee and the encounter had not ended well for the radio.

Damage to keypad
Coffee damaged keypad

Once the radio was disassembled we could see the damage to the circuit board. With a bit of gentle persuasion some of the keys were returned to life with a stiff brush and some isopropyl alcohol, but others were beyond hope and needed replacing.

Damaged switches
Coffee has got in to several of the switches. Not all could be saved and so would need replacing.

MyGoodLadyWife agreed to do the surgery for us on this occasion and after cleaning the coffee stained area thoroughly she then removed the dead switches.

MGLW removing dead switches
MGLW gathering up the removed dead switches.

MGLW then cleaned up the circuit board ready to receive new switches. The original JRC service manual lists a part number that allowed us to buy the exact replacement part from Farnell which was lucky indeed. They were cheap too, so we bought a good stock of them in case more are needed in the future.

The switches are removed
MGLW has removed the dead switches.

Finally, the part MGLW likes best – soldering in new parts. Within a few minutes the new switches were fitted and we were re-assembling the radio ready for testing.

All repairs done
MGLW has finished the repair. Now to re-assemble and test.

So… power on, tune up and… it works! I’ll do some experiments over the next few days and post up some of the results…

3 thoughts on “Repairing a poorly radio receiver”

    1. Hi Ben. The switches are from uk.farnell.com – Farnell part number 182-9495 and it is called “B3F-1022 – Tactile Switch, Non Illuminated”
      Hope that helps!
      73s

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