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Building an iPod Adapter for Vintage Radios
Many antique radios and TVs have a Phono jack that lets you connect
a record player. This article describes a simple adapter that lets you plug an iPod or
similar audio device into that jack.
With this adapter, your vintage radio can play anything from your iPod: recorded music,
old-time radio shows, audio books, or content streamed from the Internet.
The adapter converts your iPod's stereo output to mono and boosts the output.
It also electrically isolates your iPod from the radio chassis, and best of
all, it requires no power!
Here's a photo of the completed adapter, mounted in a little
plastic project box.
The next photo shows the adapter's internals. Also shown are my iPhone, a standard iPod/iPhone audio/video cable, and a standard audio cable with phono plugs.
Schematic and Parts List
The iPod adapter can be built in an evening and it uses common parts
available at Radio Shack and similar sources.
For your convenience, I listed the part numbers of Radio Shack parts that I used.
Note that Radio Shack may change part numbers or discontinue products at any time,
so if you don't find those exact part numbers, search their website (or another
supplier's site) for comparable items.
Here is the schematic diagram:
Building the iPod Adaptor
In this simple adapter, the layout of parts is not critical. I used a ready-made
plastic project box, but you could use anything similar, even a large pill
bottle or 35mm film container.
You'll need to make holes for two phono jacks (the inputs) on one end
and one phono jack (the output) on the other. I drilled holes
and enlarged them a bit using a Dremel tool. You could also melt holes
with a soldering iron.
I glued the transformers into the box and connected the few
parts using point-to-point wiring.
As shown in the previous photo, you plug the two input plugs into
the pair of jacks on one end, and the single output plug into
the single jack on the other end.
I used phono jacks for the input because I use an iPod audio/video
cable to play music or movies on various devices. If you prefer,
you can substitute a stereo mini jack and matching cable for the input.
Using the iPod Adaptor
If your radio has a jack labeled Phono, simply plug
the adapter's output plug into that jack and switch your radio to Phono mode.
For instance, here's the Phono jack in the back of my
Stromberg-Carlson 440M console:
The iPod adapter mixes the stereo input to mono and it boosts the
output to make a good match for vintage radios. If you connected
your iPod directly, you would likely find the volume too low, compared to
traditional inputs.
A few 1940s radios had jacks labeled TV or Television.
These are also audio input jacks, designed for use with rudimentary prewar
TVs that lacked built-in audio. If your radio has a TV jack, you can use it
like a Phono jack.
Credit Where Credit is Due
I built this adapter using plans published in an
Antique Radios forum
discussion
and the schematic is reproduced by permission of its creator, forum
member processhead.
That discussion includes some talk of how the adapter works and
some alternative construction techniques. Thanks to forum members
Pbpix, processhead, and others for all of the good ideas.
This radio construction project, including all descriptions, diagrams, photos, and the underlying electronic design, is published here for the noncommercial use of radio hobbyists. You may print and reproduce these project instructions for your personal use. Commercial use of this material is not authorized.
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