AM/FM Radio

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Turbo4whl

Supporting Member
Supporting Member
Joined
Oct 30, 2019
Posts
3,347
Reaction score
7,938
Location
Downingtown, PA
First Name
Wayne
Truck Year
1974
Truck Model
Jimmy
Engine Size
350
Is this what GM called the multiplex stereo or something like that?
I think that meant the tuner would grab the FM stereo signal if it was available. Usually lit a light too.

The reverb dash control I don't have, stated Reverb.
 

j69shep

Junior Member
Joined
Apr 24, 2025
Posts
15
Reaction score
12
Location
Scottsdale, AZ
First Name
jim
Truck Year
1978
Truck Model
C10
Engine Size
350
Upon further examination that’s a Motorola reverb. I don’t have a schematic for it. I’d need to get a closer look at the inside of the unit to figure out power, input and output. Yes these units typically had a 3 position switch on the dash that switched between front speaker reverb to rear speaker and reverb off. It looks to be a 65 unit. I’m not sure which models came with the Motorola unit. Maybe a riviera. Not sure. If you can get me a good shot of the inside of the unit near that 4 pin connector I could get you a good educated opinion.
 

Turbo4whl

Supporting Member
Supporting Member
Joined
Oct 30, 2019
Posts
3,347
Reaction score
7,938
Location
Downingtown, PA
First Name
Wayne
Truck Year
1974
Truck Model
Jimmy
Engine Size
350
@j69shep Looks like a lot going on from the drawing of the dash control. Transformer and other components beside just the switch control. Without that I am done.

I'm at camp today on staff for a scout activity. I send pictures later
 

j69shep

Junior Member
Joined
Apr 24, 2025
Posts
15
Reaction score
12
Location
Scottsdale, AZ
First Name
jim
Truck Year
1978
Truck Model
C10
Engine Size
350
Okay sounds good. Can I ask what this is going into? I'm not sure you need the transformer it's likely just used of coupling anyway. The 67 and up don't use it. With that you could just use a 3 way switch to turn on and off the reverb and front speaker. I'll see what I can come up with once I hear back from you. Enjoy the day. Jim
 

Corvette Ed

Full Access Member
Joined
Nov 29, 2020
Posts
3,880
Reaction score
14,679
Location
East Tennessee
First Name
Eli
Truck Year
79
Truck Model
C10
Engine Size
250
I used to find them at pick and pull yards. Most had problems with scratchy controls. Bought cans of spray contact cleaner and drenched the inside with it while moving the knobs. Nearly everyone one came out of it. In the last few years those radios have dried up.

Keep in mind GM used the same radio in cars. Only mounting brackets and knobs were different.
I’ve picked up several at swap that didn’t work or unknown condition from free to $5. A lot of the time contact cleaner will do the trick!
 

Latest posts

Forum statistics

Threads
45,579
Posts
986,819
Members
38,671
Latest member
Mavric16
Top