'71 Radio Troubleshooting
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 793
Likes: 11
From: Grafton MA
'71 Radio Troubleshooting
Hi,
The original (mono) AC Delco radio in my '71 LT-1 recently started acting up. The radio will work for a while, then out of nowhere the volume will fade quickly to silence. If i turn the radio off and then back on again sometimes it will start playing again...or sometimes i have to leave it off for a little while for it to start working again. Based on this behaviour I'm thinking it may be the radio and/or amplifier (as opposed to the speakers) but don't know how to test these.
Any tips on how to diagnose the problem would be appreciated.
Thanks,
Paul
The original (mono) AC Delco radio in my '71 LT-1 recently started acting up. The radio will work for a while, then out of nowhere the volume will fade quickly to silence. If i turn the radio off and then back on again sometimes it will start playing again...or sometimes i have to leave it off for a little while for it to start working again. Based on this behaviour I'm thinking it may be the radio and/or amplifier (as opposed to the speakers) but don't know how to test these.
Any tips on how to diagnose the problem would be appreciated.
Thanks,
Paul
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 793
Likes: 11
From: Grafton MA
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
With ignition OFF, give the radio volume **** several full turns CW and CCW. That will allow the potentiometer wiper to rub any dirt and/or corrosion off the windings. If that solves your problem, so be it. There is a spray cleaner than you can shoot in dirty 'pots', if needed.
If you have replaced the speakers in your car and kept the original Delco radio, there could be an impedance mis-match which could cause the amplifier section to run 'hot' (over-current condition). If this is the case, please fill in some gaps on how many speakers, how they were wired, and what their impedance is. If done properly, there will be no issue with the setup. But modern speakers have much lower impedance than the ones installed in C3's; and lower speaker impedance means higher current draw by them.
If you have replaced the speakers in your car and kept the original Delco radio, there could be an impedance mis-match which could cause the amplifier section to run 'hot' (over-current condition). If this is the case, please fill in some gaps on how many speakers, how they were wired, and what their impedance is. If done properly, there will be no issue with the setup. But modern speakers have much lower impedance than the ones installed in C3's; and lower speaker impedance means higher current draw by them.
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 793
Likes: 11
From: Grafton MA
