Bearcat III light repair

[N4GK]

Anyone know how to repair a scanning light bulb for a Bearcat III? I’m donating it to a place for old radios, but one of the lights is out and I want to repair it. Any ideas?

 

[tvengr]

Does the channel work or is the light just out? If the channel doesn't work, it may be the switching IC. IC7 is for channels 1-4 and IC6 is for channels 5-8. Part# is SN-7426. The lights are not bulbs. They are LED's with a 1.6v forward drop at 20ma. Each LED has a 470 ohm resistor in series with it. I would check for bad solder connections in the channel not working. You can also try cleaning the associated switch.

 

[N4GK]

Does the channel work or is the light just out? If the channel doesn't work, it may be the switching IC. IC7 is for channels 1-4 and IC6 is for channels 5-8. Part# is SN-7426. The lights are not bulbs. They are LED's with a 1.6v forward drop at 20ma. Each LED has a 470 ohm resistor in series with it. I would check for bad solder connections in the channel not working. You can also try cleaning the associated switch.

I already fixed it.

 

[tvengr]

I already fixed it.

What was the solution?

 

[N4GK]

Took the crystal out for that channel. Apparently, it was bad.

 

[arlo]

I found a shorted crystal.