Highlighted Radio Restoration Projects
Adapting an Old AM Tube Radio to Play MP3s September 08 2014, 0 Comments
These old radios are woefully behind the times in their design. But, they can be easily adapted to play MP3 using your iDevice, SmartPhone, or other MP3 player.
All you need is:
1. 3.5mm jack mono
2. 2 or 3 position toggle switch DPDT
3. 3.5mm to mono RCA cable
1. Solder iron
3. About 24” wire 18-24 AWG solid or braided
4. wire snippers
Here’s a Magnavox AM tube radio that will be converted to play MP3.
This Magnavox model R5 was made in 1957. Right now, it only plays AM radio. It has duel speakers and features vacuum tube amplification that sounds great. Your iDevice, MP3 player, smartphone plays your favorite music but its audio fidelity is passable at best.
How about getting the best of both worlds? Plus, the Magnavox retro looks isn’t too harsh on the eyes either!
Here is the Mag opened up to reveal all the lovely tubes that glow orange when it’s turned on. Isn’t that sweet?
The painful part is cutting into the radio original back panel to fit the toggle switch and 3.5 mm jack. This is not a reversible modification so be sure it’s what you really want.
Here it is with switch and RCA plug.
Here’s the back side:
Cut into the circuit before the signal goes into the volume potentiometer. This way you can use the Am radio’s original volume knob to change the loudness. You also have the volume setting on your player device to vary the loudness.
Here is where you cut into the circuit with switch and auxiliary input.
Here’s what it looks like applied to this radio’s circuit board.
It’s important ground the lead from RCA jack to the radio circuit ground or chassis. Most of these old radios did not feature a third plug or negative plug to differentiate positive from negative.
Here is an old original plug next to a modern polarity keyed plug.
Here’s the modern plug cord hard wired to the radio circuit board.
Here’s the finished product with MP3 conversion:
Hear it play on my channel on You Tube. https://www.youtube.com/watch?v=wb6yuy8gkX0&list=UUNXdUWfWZHpaDdrOyesz1Cw
Western Air Patrol Radio Restoration Project August 07 2014, 0 Comments
It was a Saturday morning in May and I was a little excited. I had gotten permission from The Wife to spend the day trolling for old radios and in particular I was going to visit Burlingame TV & Radio Todd the owner operates the store in a cozy strip mall in Portland, OR. Todd’s father started Burlingame TV & radio in 1952. Todd had a lot of great old radios and televisions, but this one caught my eye.
It was a rare brand, Western Air Patrol and wood from one of my favorite eras, the 1930’s. But it was in need of some serious TLC so I picked it up for about $20.
My first steps after I make a great find like this is to do a little research. There are some great websites out there that provide good information on radio models over the years. One of my favorite websites is RadioActticArchives.com
On RadioAtticArchives.com I found these other 1935 Western Air Patrol 4G2T as an example of how it should look.
Now I had an idea of how the original radio looked back in 1935. With this information I could now begin the best part: the process of turning this old beast into a beautiful singin’ lady.
This one had been a little mistreated; an amateur painted it in white latex paint and had even painted over the grill for the speaker. The wood cabinet was cracked and peeling in a few places. However, the wood veneer on the front and top of the radio was in condition. Of course, it was missing knobs (that always happens!)
Aside from these problems there was another thing. It didn’t work at all. The only sound this could produce was a loud crackle and some humming. This is why I love these things. After I get through refurbishing the outside, I will get to work giving this thing its voice back.
Now, Step 1 is to strip the paint. You can see it below. I use an environmentally friendly paint stripper made from oranges. It takes off the paint without marking up the wood below. It works well and I use it mostly because I have small kids and the fumes can be unhealthy.
This is a messy job but when all the paint removed, the radio looks like this:
Now, the front fascia didn’t respond well to the paint stripper and moisture. It buckled and separated so I used some wood glue and masking tape to bind it back together.
Next Step, I disassemble the radio almost completely. I have to examine all the parts to see where the damage might be. But I also use this time to clean everything up.
I always remove the back panel. This is a rear view with electronics removed:
When I first brought the radio home I plugged it in and it hummed loudly.
At that point I knew I had to restore the electronics. Now, that I had cleaned up the outside and inspected the components, I was ready to restore the electronics. I had a plan to test the circuit voltages and the vacuum tubes. I already knew that all the capacitors were dried out and needed to be replaced.
Online I found an accurate circuit diagram at NostalgiaAir.com. I used that circuit diagram as a reference to guide part of the restoration. Take a look below, the schematic was hand written, drawn with ruler and hand drawn symbols! Incredible!
For the restoration I replaced all filter capacitors and I replaced a few resistors too. It sounded a little weak after replacing out-of-spec components so I adjusted some of the wiring.
Now the transformer on this unit had an adjustable coil sleeve that had come loose and was sliding back and forth along the solenoid.
With the electronics in good working order I next began to complete the exterior restoration. I refinished the wood cabinet. I painted trim brown and gave it am clear coat with semi-gloss. I like the finished result.
Then I used brass cleaner to remove oxidation from round dial bezel. The dial glass was cleaned and the damaged dial face while replacing light bulb. This unit used two 57 pilot light bulbs. Bulbs were soldered in place. There were no sockets.
Here, you can see it posted for sale at Retroradiofarm.com on June 2, 2014
The project from start to finish lasted about three days, just a little weekend project. Now, what’s next?