This page will feature the following radios:

Zenith Model 5S29

RCA Radiola RC33


My first exposure to electronic equipment was broadcast radios, that is the radios that everyone listened to on a daily basis. This was a time long before television and the average person's connection to the rest of the world was through the voice coming out of the radio. The radio in most homes was a prized possession and children generally weren't allowed to touch them.

Like every kid my age I listened to the radio shows of the day but I was more interested in what made the radio work, and of course, I wanted a radio of my own. You can read about my first radios on these pages.

As I mentioned before, as work has slowed in my regular business I have become interested in restoring some of the old broadcast radios that were stacked in the bone pile in the back room of my shop. Friends have brought in many old pieces of equipment for me to bring back to life.

Back to the top of this page

Zenith Model 5 S 29

Here is an example of a radio a friend brought in. This radio was popular about 1935 and I found it listed in Rider manual 7-5. It has a 5 tube chassis, which includes these tubes, 6A8, 6K7, 6B6 (6Q7), 6F6, 5Y3. It has an odd IF frequency of 252.5 KC (kHz) and another feature is it has an un-tuned pre-selector. Besides the regular broadcast band there are 2 short-wave bands 1.5 to 4.2 and 6.5 to 18 KC (kHz).

Zenith 5S29

The cabinet is constructed of solid wood with what appears to be walnut veneer. When this radio was brought in not only did it need some serious work on the electronic components, but also I noticed the finish was badly deteriorated and the veneer was separating on the front curved sides.

Using some home made clamps and some thin glue I was able to repair the veneer. I cleaned up the finish using Hornbey's refinisher and lots of elbow grease. I did need to add a little stain on the top where the finish was nearly gone along with the color. I completed the cabinet finish by spraying on several coats of satin polyurethane. I smoothed the finish between coats with a very fine steel wool.

The chassis of course needed all new "caps" (capacitors), dial belt, and new rubber mounts for the tuning condenser. I am happy to say that this very classy looking radio now performs very well, even with a short wire antenna. There is no comparison for the sound of an old wood cased radio, the sound takes me back to my youth, the only thing missing is the sound of the old programs like Little Orphan Annie and The Shadow.

Back to the top of this page

RCA Radiola RC33

Zenith is a name that is very common, in fact there are few radio owners that didn't own a Zenith set or know someone who did. Another very common name over the years is that of RCA.

But how about the set known as the RCA Radiola RC33? I haven't found too many people that remember this model. This set was purchased at auction; it is such an unusual radio I wanted it for my collection. When I bought the radio the top was missing its frame, which would have been a die-cast pewter type construction matching the cabinet corners. The radio did not work and my investigation revealed that there an open voltage divider resistor in the power supply section.

The circuitry for this radio includes a tube complement is 4 - UX226, 1- UV227, 1 - UX171, and 1 - UV280. It is a TRF style circuit. The first RF was un-tuned followed by 2 of the other 226ís in a tuned manner. The 227 tube is the detector driving another 226 first audio with the 171 as audio output. The UV280 is the rectifier. I found a full schematic in my Riders manual 1-28 which indicates that the vintage is 1928/9.

You can a peek inside by clicking here. This radio cleaned up very nicely and I did not need to do any restoration to the metal case with its wood base. A friend of mine constructed a wood frame to hold the metal top from falling on top of the tubes. I have not been able to find a replacement of the original frame. Of course I'm sure you've noticed the lack of a speaker.

I do not have the external speaker that would have been used with this set. It would have been a high impedance unit such a morning glory style.

Back to the top of this page

RCA 99

The next set I'll feature is not nearly as showy; in fact I received it "as is." Which translates to, "just the chassis, no cabinet." This is the RCA 99K.

My Riders Book 9-117 indicates this radio dates sometime during the years 1939 or 1940. It's 8-tube chassis featured electric push-button tuning. As I mentioned it was obtained without a cabinet, just the front wooden panel that was once part of the original cabinet. I have no picture of this cabinet but the research indicates that it was a chair-side style.

The restoration took several new caps and lots of time to get the electric tuning working. The plastic push buttons were replaced as the originals were badly deteriorated. The performance is very good with a short antenna Wire.

I hope to have a cabinet built that will replicate the style of the era since the original is not available.

Click here to return to my Restoration Page or here to return to my Home Page

If you want more information please send me e-mail.