AUX input jack for 67-72 AM radio

[blkcorvair]

Here is my simple install of a Stereo type 1/8” input lack into my stock 67-72 AM Radio. This allows for the use of any low signal output to be played right through the radio without sacrificing the AM portion of the radio. Such devices like an MP3, Ipod, or portable CD player, or in my case my adroid phone with Pandora app. You won’t need any separate switch. The stereo jack used will give priority to any device plugged into it. And when the device is remove from the jack your AM radio will function as it normally would.
This is a pretty basic install and with a few basic tools and a careful approach nearly anyone should be able to do this for about $20 including the 3’ patch cable.

You’ll need to visit your local radio shack and obtain a pack of small resistors 1k or 2k ohms and an 1/8” Stereo Phone jack (Closed circuit) If you don’t have one already grab a 3’ or so patch cable. (This is a standard headphone type end)

Below is a diagram I found very useful that I found out on an antique radio forum. Basically you’ll need to remove the top cover of the radio and locate the blue wire from the volume potentiometer to the circuit board. You’ll be installing the input inline between the board and the pot in this circuit.



First I assembled and soldered my input jack. If you are installing the jack in a ground metal opening then there is no need for a ground wire and the #1 terminal need not be used. The two resistors get soldered together at the #5 and #2 Terminal and then one lead gets attached. The #3 and #4 terminal get “jumped” and than a second lead will be attached. For the leads I used some old thin speaker wire off an other radio I had.




I than removed the chrome face of the radio and located and drilled a 15/64 hole all the way to one side. (I wanted to be sure the AM dial needle would not hit my stereo jack inside the radio once completed) Be sure to carefully de-burr the inside and outside edges of the new hole.



The terminal lugs on the back of the stereo jack are very close to the edge and once installed could ground out on the inside edge of the faceplate. So I slightly bent the terminals inward with a needle nose pliers and put a few small scraps of heat shrink tubing in different spots. Im sure electrical tape would work fine too. I than carefully installed and tightened the stereo jack into the faceplate.



Once I fished the leads into the case and re-installed the faceplate I was ready to connect the leads.
I “de-soldered” the blue lead at the circuit board. The lead without the resistors was than soldered in its place. The lead with the resistors is than soldered to the blue lead going to the potentiometer.

And that’s it! I used a small wire tie to keep all the leads away from the dial and put the top cover back on. Check out the picture below of my Android playing music through my radio.













Just so everyone is aware. Im in no way any kind of electronics wiz. I used all this info that I found on the net and combined it to set up a 67-72 Delco AM radio as shown above. I plan to install this in my truck and don’t forsee it will damage anything but do this conversion at your own risk.

Below are a few links to other people who have posted thier "succesful" conversions and from where all my info has come from

http://www.antiqueradios.com/forums/...p?f=6&t=166720


http://www.spridgetguru.com/TA0041.html

http://autoxer.skiblack.com/nallm/mp3jackinamfm.htm

[VA72C10]

very cool! recommending for an FAQ!

[oldblue1968chevy]

awesome

[GCncsuHD]

Great job, I did a similar conversion on the stock BOSE radio in my 2003 GMC Duramax a few years ago using the same stereo jack.

[blkcorvair]

I forgot to mention. If you make the wires longer there is no reason you cant install the input jack somewhere on the dash or even in the glovebox out of site. (Just if it is not installed in grounded metal you must add a ground wire to the #1 terminal.)

[cjohnson6772]

Very very slick. I am now on the hunt for a stock AM radio and will be selling my ken harrison piece of junk!

[kvn1011]

Nice!
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[camaney]

great.. no i can do it my self

[70 supersport]

Does it work the same for a factory am/fm radios?
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[70 supersport]

Will it work the same for a am/fm radio?
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[blkcorvair]

Originally Posted by 70 supersport

Will it work the same for a am/fm radio?
Posted via Mobile Device

I would think it would as they were mono as well. If you open the cover and it has three leads into the potentiometer I'd say your good to go. Ive only done this one, but Ive heard it relativly easy to do to a "stereo" radio as well. Never tried....Yet.

[71meangreenc10]

Do you only use "one" speaker with this mod or did you add something for multiple speakers?

Curious......

Smitty

[oldgold70c10]

Originally Posted by 71meangreenc10

Do you only use "one" speaker with this mod or did you add something for multiple speakers?

Curious......

Smitty

It uses the stock speaker and stock radio....just lets you connect an ipod, mp3 player, or cd player to the radio.

[blkcorvair]

Originally Posted by oldgold70c10

It uses the stock speaker and stock radio....just lets you connect an ipod, mp3 player, or cd player to the radio.

Thanks

[chevy88]

Will a 3 terminal 1/8" input jack work instead of a 5 terminal? Can't find a 5 terminal, and from my understanding you are just taking the left and right speaker side and putting them into one as you are just hooking up the one original speaker.

[red71c10]

Perfect! That is just what I want! To be able to keep the factory radio and have an easy way to run my iPod through it! I know I can do that! I'll have to buy a new speaker to go along with the input install!

Very Cool!!!

[tommyd241]

Very cool!

[chevy88]

To save people looking up parts, here are the part #'s from radio shack.

The resistors in picture are 1k ohm 1/4 watt. part # 271-1321 package of 5 for $1.19

1/8" stereo panel mount phone jack with 5 terminals. part # 274-0246 for $2.69

Original replacement speaker 4" x 10" delco style special rectangular $49.95
Phone # US 1-877-780-2861 or outside US 1-763-780-2861 here is website http://www.turnswitch.com/speakers.htm

I jumped the gun and ordered 2k ohm resistors 1/2 watt before I knew what was exactly in the picture can some one tell me if this matters???

[Kidd-7]

Originally Posted by chevy88

I jumped the gun and ordered 2k ohm resistors 1/2 watt before I knew what was exactly in the picture can some one tell me if this matters???

It will not matter, they may be a little larger. That rating only has to do with how much power before the smoke comes out of the resistor...

[MistaGavin]

Just got my parts for this upcoming small project. Resistors and 1/8 jack were a whopping $3.88

[Normru45]

very cool, just posted somthing kinda on the same page as this but i really like what you have done!

[claytonisbob]

This is too awesome! I am going to do this this weekend.

[MistaGavin]

This is very cool. I think I will do this as well.

[Bassetlounge]

I am about to try this myself.. How have the others done implementing this? Anything to watch out for? I assume the radio still works if the aux jack is unplugged?
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[BBrendal]

Sweet!