Bearcat III Electra Scanner with hum

[jdeverett]

Hi all,
I just obtained a Bearcat III electra crystal scanner and it has a humming noise from the speaker. I am looking for some ideas on what this could possibly be. I was thinking a tired cap... We still have a lot of old solid analog systems here on the North East Coast. Nothing beats the old flashing LED's and solid sound from this old rigI have many new digital rigs but I needed those flashing lights. Also is anyone aware of any shops that have parts available or do quality repairs.

Thank You

 

[N_Jay]

Yep, first guess is a bad cap in the power supply.
Second guess is AC on the ground of the antenna (ground loop issues)

Does it go away if you unground the unit? (including disconnecting the antenna)

If so, then try flipping the AC plug and checking your antenna ground.

If it does not, then it is almost 100% a bad power supply, most likely a bad cap from age.

 

[pro92b]

You can get a service manual at mods.dk – manuals

I would replace all the electrolytic capacitors, marked as "Lytic" in the service manual parts list.

 

[gewecke]

exactly as he said. I would start with filter caps first.
N9ZAS

 

[tglendye]

Can't contribute anything more, but the Bearcat Electra III was my 1st scanner- and I loved it!!!

 

[DELTA60]

Ah Yes, those were the days..the Bearcat III was my first scanner also. I remember ordering the cyrstals and having to wait on them to come in

 

[jdeverett]

Thanks all for your help.

W2WEG