Trutone Radio Model D2634

Circa 1947

This set was my first antique radio and has always been one of my favorites. I purchased it in 1995 at the Tulsa Flea Market for the lofty price of $7. The cabinet was in rough shape and the chassis was just sitting in the cabinet. All the knobs were missing. Surprisingly, after reconnecting a wire that led to the speaker, the radio worked, and worked well. I spent many hours listen to programs such as Bruce Williams and Art Bell with this set.

Above is a picture of the radio. In 1997 I had the speaker re-conned professionally by Speaker Works in Tulsa (I believe they are no longer in business). Since the chassis and speaker are all one unit, I had an empty cabinet for about a week, so I sanded and re-stained it. This is the only radio cabinet I have ever refinished. I also used some rub-on transfer letters to identify the knobs. From left to right the knobs are: Volume/on-off; phono/tone switch, and tuning. The phono/tone switch is a six-position switch that give high-medium-low tone for radio, and high-medium-low for phono. This eliminates needing a separate tone control and radio-phono switch.

The tuning range of this radio is 540Kc to 1620Kc, the standard AM broadcast band. The Intermediate Frequency is 455Kc.

 

You may be asking yourself at this point "where is the tuning dial?" This radio had a slide-rule on a clear plastic part  that went just above the "window sill" over the control knobs. The scan below from the Rider's manual should give you a clue to its appearance.

A lead coupling is attached to the dial chord which stays with the chassis when you remove it from the cabinet. This coupling engages a pin on a slider that slides on a metal track. To this slider, the dial pointer is attached. I had made a dial pointer from an old red clock seconds hand years ago, but it broke off when moving the radio a while ago, and I haven't replaced it yet. If anybody has a dial scale for this radio, please email me because I would love to have one.

Above, a picture of the radio's interior. With the exception of the two middle tubes, all are the same ones that came with the radio. One tube was eventually replaced because it became microphonic (the 6SQ7) and another was used in a substitution in another radio, and I haven't switched them back yet. The following table gives the tube line-up as well as the brand names of the tubes as they were when I purchased the set.

ID Type Function Brand
V1 6SK7 Radio Frequency Amplifier Ken-Rad
V2 6SA7 Converter-1st Detector Ken-Rad
V3 6SK7 Intermediate Frequency Amplifier Ken-Rad
V4 6SQ7 Detector-AVC-1st Audio Amplifier Ken-Rad
V5 6V6-GT Beam Power Output Sylvania
V6 5Y3-GT Rectifier RCA

I have several radios with the RF stage ahead of the converter, but only a few with a 3-section tuning capacitor. This radio is one of those. Thus the input and output of the stage is tuned, resulting in much improved selectivity. In this radio, the tuning capacitor  is inside the chassis, and the oscillator coil for the mixing stage is in a square can on top of the chassis similar to the IF transformers, but shorter.

The audio section of this radio is very fine for a table top radio. The 8" speaker has very good bass, and with the tone control set to the bass position, the bass is boost quite a bit, giving so-called "rich" reproduction, as the service sheet for this model claims. I liked the audio section of this radio so much that I actually designed and built a modified stereo version of it, my popular 5 tube stereo amplifier.

Above is a close-up  of the radio's interior. This radio has an electro-dynamic speaker, that is, it uses an electromagnet for the speaker field as opposed to a permanent magnet. This field also serves as a filter choke for the radio's power supply. The chassis is made of very heavy gauge steel, and for its size, is very heavy.

Trutone was the brand name for radios sold thru Western Auto stores. With very minor modifications to the cabinet design this radio was also sold in Gamble-Skogmo stores under the brand name Coronado. I have actually found that the schematic and chassis drawing for the service info on both versions to be identical. The chassis was used in quite a few different models, and with a separately mounted speaker can even be found in console sets. You can see many of these by simply flipping thru Rider's Perpetual Troubleshooters manuals from the era.

Service Data:

Riders Volume 18, Western Auto Page 18-29 and 18-30.

Back to the Radio & Electronics Page