• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

Old electrolytics

mechanic

Well-Known Member
Mar 4, 2009
596
126
53
North coast of the USA.... Da UP!
I have been running into some problems with some radios I have and friend's rigs as well. Also surface mount electrolytic caps in some SONY receivers, after replacing them the receivers came back! As they are aging, seems to me that electrolytic caps are starting to die, short out or open up. Example is the display caps on the 2510, I have two old and dead Cobra 148GTLs from the eighties and they only work partially, wondering if the caps have gone South...... :confused:
Any input on this would be of great help

mechanic
 

I have been running into some problems with some radios I have and friend's rigs as well. Also surface mount electrolytic caps in some SONY receivers, after replacing them the receivers came back! As they are aging, seems to me that electrolytic caps are starting to die, short out or open up. Example is the display caps on the 2510, I have two old and dead Cobra 148GTLs from the eighties and they only work partially, wondering if the caps have gone South...... :confused:
Any input on this would be of great help

mechanic
Solder connections degrade over time as do other components.
 
yes, electrolytics do dry out, and if a radio is over 20-25 years old, this is something to suspect when things go south.

there are a couple of caps in the 148gtl that can either kill all the receive audio or kill all the TX power if they go.
i think C95 is the one for the receiver.

i LOVE old MB8719 radios and i replace all the electrolytics in them when i buy one.

turns the radio back into a brand new radio in my experience.
LC
 
Especially suspect are the ones rated at 10 volts. Like loosecannon said, it returns the radio back to new. I have a Uniden PC122 and an RS HTX100 both had some old 10v caps that had outlived their usefulness and caused transmit problems. I recapped them both and they work GREAT now.
 
i second what warbird said.

the 10 volt caps are usually the first to go, especially when they are part of the audio section of the radio.

i have my own theory on why this is, but it is just that; a theory.

i think that when radios are modified for more modulation and power, that voltage spikes that exceed the 10 volt rating occur, and these transients cause the caps to break down over time.

just my thoughts on this,
LC
 
I had a Uniden Grant that burned out a couple of internal and external speakers. Turned out a shorted electrolytic cap allowed DC to the speaker and in a short time.....gone.
The Taiwan Cobra 148 GTLs are famous for dried out caps.
 

dxChat
Help Users
  • No one is chatting at the moment.
  • dxBot:
    Tucker442 has left the room.
  • @ BJ radionut:
    LIVE 10:00 AM EST :cool:
  • @ Charles Edwards:
    I'm looking for factory settings 1 through 59 for a AT 5555 n2 or AT500 M2 I only wrote down half the values feel like a idiot I need help will be appreciated