Tube Radio Restoration
Intro: Tube Radio Restoration
This instructable is for a 1948 philco 48-200i case restore.The "i" in 200i stands for Ivory. This is a fairly common radio but it immediately interested me when I first saw it. Only it wasn't in the best condition cosmetically but it reminded me of a old truck in some ways. And I like old trucks. These radios came in two colors orignally, which were mahagony, and ivory. Restoring these old radios is a hobby of mine and I just love seeing them go through the before and after. In this I will briefly show you how I did it. The cost of this restoration as far as the cosmetics go was less than $10 total. In the picture I have posted my finished product as well as what the radio looked like before I redid it.
STEP 1: Preparing the Case
The first thing you got to do is remove the chasis before you can proceed with the case. These radios are great for that reason. They are fully serviceable. Just four screws under the case and it slides right out. Something you can't do easily with more new radios. While I had the chassis out, I went ahead and redid the capacitors(although it didn't hum) and cleaned out the tuneing components. All this was a job unto itself. Other than that It needed a new tube installed and a dial light bulb. The rest of it worked as it should. I didn't do anything to the dial face because I wanted it to have some originallity left in it for that nostalgic feel. As you can see from the pictures how they built these radios in the day was great, nothing in it was cheaply made, all the components were metal and made to be replaced if broken. The hardest part is locating them if they are broken in todays world. But the engineering was just well done and in the USA.
STEP 2: Power Cord
The power cord was appauling. Years old and grimy it was just nasty. It had to go!! Replacing a power cord was easy in this situation. It doesn't have a transformer to connect to in this model, instead it connects directly to the on/off switch and also to a tube. I found that interesting but hey it works. Just two solders and a knot to stop it from pulling out and thats that! The pictures speak for themselves.
STEP 3: Prep Time
With that all done I was ready to paint. I turned on the chasis in the background while I worked to make sure it was ticking properly before putting it back together. Preping the radio wasn't hard. Just a good ol' scuff sanding. I covered the dial lense and holes with painters tape to keep out paint where it shouldn't be. From the picture you can see the ivory color but it had been repainted sometime ago. Once I prepped it, I just had to choose a color for it. I wanted to two tone it to give it some personality. So I chose blue and white. White for the speaker grill and blue for the rest of the case. I used krylon peekabo blue. Both were a gloss finish paint. With the music going in the back ground I went to town on it. For the white I just went over the entire case with it getting it nice and wet with two coats. After it dried enough, I taped off the grill area with painters tape and scuff sanded the rest of the case and followed suit with the blue, and for that I did 3 light coats. The white undercoat gave it a nice brightness under the blue. The knobs I did separately and those were more of a challenge due to years of oil and who knows what.
STEP 4: Finshed!
After a good day of drying I put it back together. And behold its glory! So much better than it was. It definetly was one of my more easy restores. A lot of these old radios don't have spare parts and some parts are impossible to find so it does come down to having to get creative and make your own parts sometime. Knobs are a huge issue with radio restorations, they are the most handled part of any radio and easily get broke or lost. So it was amazing to me how complete and well taken care of this one was when it came in my path. A lot of my other radios that are waiting for restoration are missing knobs and other pieces that they just don't make anymore..unless I had a time machine... but I don't so unless I could just print them out like on paper I'll just have to come up with other solutions.
18 Comments
Mtixe72 6 years ago
Sparker94 6 years ago
Hello, I would first say does any of the tubes get warm or light up? if they do, you got power coming into the chassis, however if all tubes or cold and none light up, I would see if it has a transformer (some do and some don't) like the one in this instructable does not. If you got a DMM handheld meter I would start by seeing if the wires coming into the chassis from the wall outlet have voltage. If It does, then see if the transformer (assuming it has one) has voltage coming out of the output side. if nothing is then i would say it has a bad transformer. sometimes the on/off switch is part of that circuit and may not be working either and you would know when its switched and has no voltage on either side. Now a radio that does not have a transformer you would do the same test only instead of the wall outlet wires going into a transformer, one goes to the on/off switch and the other goes to a tube. use the DMM at both ends to see if it has power applied when on/off switch is switched to "on". if it does have power the wires are good but the first tube the wires go to after tha are probably bad. Thats the same method i would try with either type of radio. Generally with a old unrestored radio, its the transformer, power switch, bad power tubes (most common and most easy to fix), and least likely would be a broken connection somewhere in the chassis so give it a good look over first then try those steps. Feel free to let me know how it goes. Thanks!
Tangski 6 years ago
Check on Ebay for vintage knobs...there are all kinds out there, and some reproduced to suit the old radios. Since this is a rising hobby, and the old is being restored now, there are actually parts out there...who knew, eh? Good luck and I loved the project!! Thanks for the hints from those below to get the right voltages etc...thanks guys! Cheers to all!
thegoom 11 years ago
And unless you are a purist you could use replacement transistors in stead of those hard to find tubes.
Sparker94 11 years ago
Tangski 6 years ago
could you tell us where you have some old stock supplied? Would be nice to order a few for others too? Just wondering if you are willing to give the information:) I have 2 old radios I would love to restore, one is from the early 1940's. Cheers and thank you!
mattthegamer463 11 years ago
Ham It Up 7 years ago
Excellent paint job! How did you get the clean lines between the two different colors?
Tangski 6 years ago
use automotive paint tape to mask off areas around the edge, and either wax coated auto paint paper to mask off the rest as you paint one color:) Hope this helps you in your project:)
SzabolcsK 7 years ago
You should consider adding a 1:1 isolation transformer for safety.
richard1947 8 years ago
The intriging question ot the line cord connection to radio is because this kind of receiver were called "transformerless", meaning that the tubes filaments are designed to get certain amount of voltage, (35, 50 and 12 volts) and since they are all series connected, the total amount is around 127 volts. The first tube connected is the rectifier, and it draws the neccesary voltage to make the circuit works. Of course, when one filament is gone, the whole receiver becomes "dead."
dsandds2003 9 years ago
Well considering I have repaired hundreds of these tube radios. I have LOTS of tips I can share. Contact cleaner works great for the scratchy volume controls. If the tuner is full of dust you use a pipe cleaner the clean between the plates for better reception.
For tubes you can leave the original tube in the set a 1n4004 works for bad section of tube diode, triode or pentode.
have lots of repair tips
LOVE them old radios!!!
zomfibame 11 years ago
RangerJ 11 years ago
mattthegamer463 11 years ago
Otherwise, great work. Glad to see someone fixed up a wonderful old device without making it "better" by gutting it and putting in some $5 powered speakers and an iPod connection, and painting it some ridiculous Andy Warhol scheme. Classy baby blue is definitely a '40s look. Well done.
Sparker94 11 years ago
Sparker94 11 years ago
Phil B 11 years ago
As concerns the lack of a transformer, these radios economized to make a less costly design. There are usually five tubes. The heating element in each is designed to consume 25 volts. The tube heating elements are in series, so in a 125 volt household circuit, 125 volts is consumed and no transformer is needed for a power supply.
It has been about twenty years since I had to buy an electron tube. They were becoming less available then. I am surprised you were able to get the tube you needed, but, maybe I should not be.
When I listened to "popular" music during my teen years, it was most often by means of a tube radio. A few years ago someone gave me a couple of old tube radios. From the two I was able to make one work pretty well, at least for a while. I listened to an oldies station with it and was surprised to rediscover favorite music as I originally heard it with all of the pops, wows, and hisses that are part of AM tube radios. The super-clean sounding FM oldies stations are nice, but, the extra noises made the experience a real authentic trip down memory lane.