RF Cafe Software
About RF Cafe
1996 - 2022
BSEE - KB3UON
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...
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Melanie and I drove 300 miles from Erie to Harrisburg, Pennsylvania, back in June of 2013 to pick up this circa 1941, Crosley 03CB floor console model radio. As can be seen in the 'before' photos, it was in pretty rough condition. The wooden console was dinged and the walnut veneer was separated and missing in places. A severe overheating condition must have occurred the last time it was plugged in because the plastic front panel knobs were partially melted and distorted. Both concentric tuning, band switching, volume, and on/off switch shafts were rusted together. It was definitely a diamond in the rough. After a year and a half of wood, metal, and electronics work, it is now what I believe is one of the fine examples of a restored Crosley 03CB radios in existence.
As the photos show, the wood cabinet and metal electronics chassis were completely stripped of all components. Paint stripper was used to remove all the original finish from the wood, and then many hours of careful sanding, gluing, and repairing were performed. The darker areas are walnut veneer, and I'm not certain what the solid wood parts are made of; it does not appear to be maple, but it is very hard - -maybe ash. A coat of Minwax Golden Pecan stain was applied over all surface to even out the coloring. No attempt was made to replicate the striated plastic stencil covering on the speaker grille rods or the solid wood parts. I decided the risk of screwing up the wood during a hand painting of the design would not be worth it. Four base coats of Minwax semi-gloss polyurethane were brushed on, sanding with 220-grit paper between every coat. Because preventing runs and/or sags on vertical surfaces is difficult with polyurethane, the final (fifth) coat was sprayed on. The result is as perfect of a finish as I have ever attained. Use of a tack rag prior to application helped obtain the nearly dust-free finish.
After all of the electronics components were removed from the chassis, it was sanded to bare metal, primed, and painted with Rustoleum enamel. All of the major components were cleaned, painted where needed, and reinstalled. Leaded resistors, capacitors, and inductors were left out - at least for now. If I live long enough and am motivated to do so, I might someday attempt to get the original circuit working again. For now, however, I settled for wiring a few of the vacuum tube heaters and the front panel lamps to light up when the power switch is turned on. A 3-wire power cord is used with a safety ground connection to the metal parts. I bought an 8' extension cord and cut it about 18" from the receptacle end, and used the plug section as the power cord. The receptacle end is on the load side of the power switch and hanging inside the cabinet so that at some point I can set a working radio inside, plug it in, and have it be turned on and off by the front panel switch.
I have searched extensively for an advertisement for the Crosley 03CB in magazines and newspapers in the 1940 through 1945 and the most that has appeared thus far is this single line of text in the July 1943 issue of Radio News. The price makes me wonder if the cabinet itself was sold without electronics since it uses the same components in the easy to find 02CA model. I found a second 03CB on Craigslist in Harrisburg, Pennsylvania, so that makes two from that region. The one featured here on this page was gotten from (Harrisburg), and my first one was from Maryland.
Farther down on the page you can see the postings I made as work progressed. There are many more photos available with a higher level of detail. If you have need of anything, please let me know.
Melanie and I have decided to eventually offer the Crosley 03CB to a museum. We will be doing research into which museum would most benefit from it. This might well have been one of Crosley's final commercial radios built prior to converting its factory to wartime radio production. Here is a brief news item from when Crosley announced it would be scrapping its 1943 line of household radios to dedicate all production to the war effort.
As the old saying goes, a picture is worth a thousand words, so here are a few thousand words for you:
(Replacement knobs available at renovatedradios.com)
November 21, 2014 Update:
As promised, here are the first of the electronics chassis restoration photos. It was decided from the beginning that the chassis would be stripped of all its components so that the metal box could be completely sanded and re-painted. That involved not just unsoldering all the individual components, but also drilling out the rivets that secured the tube sockets and solder terminals. My plan was/is to someday rebuild the original circuitry, but because I have so many other projects (both electronic and woodworking) in the works and in the queue, for now I am just going to re-install all the major hardware and wait until later to solder back in all the resistors, inductors, and capacitors - all of which will be newly manufactured components rather than trying to rehabilitate the originals. See the bottom of this page for some 'before' photos.
Dark red paint was on the outside surface and a copper type of plating was on the inside of the steel metal chassis. I decided to sand, prime, and paint all the surfaces with dark red enamel. When the discrete components eventually get reinstalled, the paint will need to be scraped off areas where ground attachments are soldered, but that will not present a problem. Melanie volunteered to perform the tedious task of removing the solder and component wire lead stubs from all the tube sockets, rotary switches, potentiometers, and other components. I titled the picture below of her doing the chore, "Melanie the Service Maid," a la the "Sally the Service Maid" series that appeared in World War II era editions of Radio Craft magazine. All the parts were then scrubbed with acetone and a wire brush, then sprayed with a light coat of clear lacquer for preservation. As with the chassis ground tabs, the other solderable areas will be scraped later to facilitate soldering.
After allowing the paint to dry for about a week, all the tube sockets and other items were pop riveted back into place. The cleaned-up adjustable capacitor tuner, tuning coils, rotary switches, a very heavy transformer (with re-painted metal shields) and other hardware were all bolted back in place. Wow, do they ever look good! I'll bet the ladies who put them in 75 years ago at the factory in Cincinnati, Ohio, would be happy to know that someone cared enough about their work to find it worthy of restoring and preserving. The dial plate, pushbutton station changer assemblies, and tubes will be reinstalled after the wood console is ready, which hopefully will be by the middle of next week (the 4th and final coat of polyurethane is drying now).
It might seem a bit cheesy, but for now I am going to re-wire all the 6.3 V tube heater pins and the front panel light sockets to get everything to glow when the power switch is turned on - just for the ambience. I'm even considering cutting off the receptacle end of an extension power cord and plugging a modern radio into it so that a radio will play when the Crosley's power switch is turned on. Hey, don't you roll your eyes at me ! :-)
The next series of photos will be with everything back together.
November 17, 2014 Update: A couple months ago I finally picked up on the restoration of my circa 1942 Crosley 03CB console radio. All of the hardware was removed from the wooden console in preparation for restoration. Paint stripper was used to remove the bulk of the original finish, and then sandpaper along with a lot of muscle power took care of the rough and final sanding. As can be seen on some of the "before" photos below, there were many places where the walnut veneer had delaminated and other where small areas where pieces had broken off. I obtained some replacement wood from a vendor on eBay and spliced in the missing areas. Delaminations were glued back in place using Elmer's Carpenter's Wood Glue. A few of the wood corner gussets needed to be re-glued as well, and some of the solid wood frame pieces had glue smeared into the joints and then clamped. 80 grit sandpaper leveled off the really out of alignment areas, and 220 grit was used to prepare everything for stain and polyurethane.
A light wiping of a walnut colored stain helped even out the coloring, with some darker stain applied to patch pieces to bring them in color alignment with the original wood. Two base coats of Minwax polyurethane were applied, with 220 grit sanding in-between. I replicated the original information label that was on the original chassis and glued it inside where the original was. A third coat of polyurethane went on, including over the label. A final sanding with 320 grit sandpaper smoothed out the foundation prior to applying the final coat of polyurethane using a foam brush. I have found that a foam brush (or unused bristled brush) is best for at least the final coat of polyurethane because it will not deposit any small pieces of crap (technical term for bits of solid contaminant) in the finish. Be sure to strain the final amount of polyurethane prior to application to eliminate all traces of crap. Also, absolutely essential to obtaining a smooth, crap-free finish is to thoroughly vacuum, blow off with an air hose, and then wipe all surfaces with a tack rag between every coat.
Coming very soon: Photos of the electronics chassis restoration process.
August 3, 2013 Update: Read about my experience electroplating copper back onto some of the mounting hardware.
June 22, 2013 Update: After searching occasionally for many years for another Crosley 03CB radio in a location close enough to drive to, I finally saw one on Craigslist in Harrisburg, PA, about 300 miles from my home in Erie, PA. Melanie and I picked it up yesterday. It needs - and will receive - a total restoration for both the cabinet and the electronics, but it appears to be in better condition that my first pre-restored Crosley 03CB. This radio is Chassis #95.
If you look at the photo below of the first radio (the one with my kids and father-in-law sitting next to it), you will notice that the tuning dial has no cover over it. I never knew there was supposed to be a glass bezel in front of the dial. Back in the 1980s when I restored that radio, the Internet was still Darpanet and 'normal' people did not have access, so research was much more difficult. I could not even find SAMS Photofacts for it in order to work on the electronics. Fortunately, I was now able to buy a high resolution scan of the original Crosley documentation for a mere $9.95 in PDF format (AntiqueRadioSchematics.org).
Here are a few initial photos of how the radio looked when I picked it up. A thorough documenting of the restoration process will be posted here over time. Before doing any of the major work, I need to complete the grandmother clock I've been working on for the last couple years. It was built from scratch using hickory wood from the local lumber mill. I'm in the final sanding phase as this is being written, so the stain and polyurethane will come soon. Then, finally, the clockworks will be mounted inside (it's already been test-fitted), glass panels installed, and the clock will assume an esteemed spot in the living room.
Console Top View
This 1941* Crosley floor console radio model 03CB was given to me as a Christmas present in 1983 by my wife, Melanie. It was found by my sister, Gayle, and her husband, Mike, in a barn on Kent Island on the Eastern Shore of Maryland. It sported a couple shortwave bands and AM (no FM in those days). Unfortunately, I did not take any detailed pictures of the unit, so the best I could come up with is this shot of my two children (Philip & Sally) sitting with my father-in-law, Marlet Goodwin, on Christmas day of 1990.
Its original finish was peeling off, and all the metal parts - the dial and trim plates, electronics chassis, etc., was rusting. It sat in our house for a couple years and then I tackled the refinishing project. Every bit of of the stain and shellac was removed from the case, and paint from the metal parts, using naval jelly (the good, caustic pink stuff). Hours of scraping, filling and sanding took care of the wood, and then a Minwax stain was applied, with a top coat of a few coats of Deft lacquer. The dial was carefully cleaned and lacquered. The dial trim plate was primed and painted gold (the original color). I removed all the tube and primed and painted the chassis gray (its original color). All the paper capacitors were replaced, and the tubes were tested on a portable tube tester that had been given to me by überengineer Jim Wilson. Only a couple needed replacing. Those were the days before eBay and the Internet, so finding replacements took enlisting the help of Ham friend who found them at a Hamfest. The antenna was a solid rectangular coil that ran around the rear outside edge of the entire chassis.
After doing a good visual and continuity check of the electronics, I plugged the radio into the wall. No smoke - that was a good start. A beautiful warm glow appeared at the base of all the tubes, and before long there was a welcoming 60 Hz hum coming through the huge electromagnetic speaker (no permanent magnet). I turned the dial and, voila!, the local AM stations came in clear as a bell (well, as a bell with a 60 Hz hum). The hum was eventually tamed by adding a couple caps across the coil. It probably killed some of the bass, but who would notice on AM? I pushed the "Japan" button and picked up some foreign station, but it definitely was not from Japan. Similarly, other far away broadcasts were received on the other bands, but I cannot recall the details.
Melanie and I gave the radio to her sister as a wedding present in 1993, since her sister's home was decorated in a Victorian theme. It has since, shall we say, "moved on," and I now have no idea where it resides. Oh well, that's the risk I took in gifting it. Here are a few of my other projects.
* I originally had 1926 as the year since I remember seeing the date on a label inside the radio, but research has shown that it is most likely a 1941 model. The 1926 date was probably for one of the patents listed.
If you have any interest in vintage radios, you undoubtedly are familiar with Crosley products. They were very different from today's Crosley products in terms of quality. My experience with Crosley was while restoring a 1941 console (floor) model that was given to me by my sister. It was constructed of solid wood and a nice mahogany laminate. The face plate, dial, and knobs were heavy gauge metal. Following the success of their radios, Crosley ventured into the automobile market from 1939 through 1952. Little known even amongst Crosley fans is that they built proximity fuses during World War II. "Crosley's involvement began in late October 1941 when they were contacted by the Bureau of Ordnance and told that they would be contacted later that month concerning a 'top secret, top priority' project." A Crosley VT (variable time) fuse was credited with the downing its first Japanese dive bomber in 1953. The Brits used them against German V-1 Buzz Bombs. Thanks to RF Cafe visitor Kevin A. for the tip.
- 1941 Crosley 03CB Floor Console Radio Restoration Project
- Tesslor R-601S Vacuum Tube Radio Teardown
- Tesslor R-601S Retro Vacuum Tube AM/FM Radio w/Bluetooth 3.0 Modification
- Crosley 03CA Floor Console Radio for Sale
- 1941 Crosley Model 03CB Radio Photos (Tim O.)
- Radio & Electronics Restoration Projects
- Vintage Ads with Science / Technology Themes
- Vintage Magazine Ads from Duke University's Ad*Access Website
- Vintage Radio Control Systems
Posted June 22, 2013