Need help adding input jack to 80's car radio

[Mark M]

New guy here. I have a mid-80s Delco AM FM Cassette radio that I am installing in a 1964 Chevrolet Corvair and I would like to add an input jack so I can connect to my iPhone. I have a cassette adaptor that works, but would prefer to have the jack so I can eliminate the wire hanging out of the cassette opening. I am willing to sacrifice the operation of the cassette if necessary in order to wire in a jack. After a search I found a similar thread, but the wiring of the radio was different than mine.

There are two connectors coming from the cassette. I believe the one I need to connect to is in photo below. There are 6 wires: Red, Wh w/red, Green, Black, Orange and Yellow. Green and Black go to the "Tape" light on front of the unit. How do I splice into the other wires to add a jack to the circuit?

Can I add a DPDT switch to select from radio, cassette and input? Or, do I need to sacrifice use of the cassette. If so, will I need to put a cassette in the unit to signal it to switch to aux input? Diagrams will help - I am not good at electrical.

Thanks,
Mark

[SuperDuty]

Re: Need help adding input jack to 80's car radio

Hi,

Here's my simple diagram :


I used it on mu UU6 radio from 1984.

The switch is precisely used to feign the presence of a cassette so I don't have to put an empty one in. When the wires 3 and 4 are shorted together, the unit will think there is a cassette, when the 5 and 4 are shorted, it will believe it's supposed to play the radio and won't use the audio signal from the cassette player.

You will have to find which wire does what on your unit, even though some colors are the same, I can't tell your they serve the same purpose. I did not have to search on my unit as I had found a tutorial on TurboBuick.com where someone was doing the same thing on a similar double DIN unit (those Delco units with three mechanical buttons under the cassette deck).

[Mark M]

Re: Need help adding input jack to 80's car radio

Thanks for the help. So when the switch is in the leftmost position you have cassette. In rightmost, radio. What do you get when the switch is in the center? Or perhaps there is no center?

Not sure I can figure out how to wire the switch in, but I think I can find left and right channels.

If anyone else has input on how to wire the switch I would appreciate it.

[SteveNielsen]

Re: Need help adding input jack to 80's car radio

You could also try tapping into the high sides of the volume pot through a couple of caps (I'd try something between .05uF and .1uF) to block any DC that may be present. Like a signal injector.

[SuperDuty]

Re: Need help adding input jack to 80's car radio

There's no middle position, there's one common wire used in the system and that's the +12V. The switch just goes from +12V/radio to +12V/cassette.

I'm sure this design could be much improved, I'm by no means an expert but I just have a rough idea on how it works. If anybody knows a bit about these units and thinks of a better way to add an AUX input, I'd be very interested.

My unit was the high end stuff in 1984 and cost an arm (it was a $510 option in 1984), it sounds really good but I need better speakers. All I have is the stock 4x6 front speakers and some aftermarket stuff I found on parts cars. Not great.

[R_J]

Re: Need help adding input jack to 80's car radio

Why not use a wireless fm transmiter, like an iTrip

[audiofreak19]

Re: Need help adding input jack to 80's car radio

Why not use a hardwired transmitter. It ties in through the antenna plug on the back of the radio. They have a kit they sell made by I simple the model number is IS77. Bestbuy sells it and I believe it included installation and it has a direct plug for the iphone and will charge it as well. It's a good deal I used to install them.