Please be patient while this picture loads... It's worth it!
Updated 08/05
Please be patient while this picture loads... It's worth it!
A page from the 1939 Sears and Roebuck catalog featuring "The Rocket". Thanks to Eric Wissing for the scan.
The Silvertone 6110 Rocket was designed in 1938 for Sears by Clarence Karstadt.
I was fortunate to literally stumble across Karstadts' patent drawing for the "Rocket". This is a large drawing and may take a minute to load. If you would like to see this work, please click here. For those not familiar with design patents, they are basically just a page or two, usually a claim page, followed by one or more pages of drawings of the design. Not a lot of technical patent mumbo-jumbo.
Recently (08/05) I found yet another patent related to the Silvertone Rocket. This patent is not credited to Karstadt, but rather to one Alonson Scriven. I must assume Scriven was an engineer or designer for Sears, as the patent is assigned to Sears. This technology patent is remarkably true to the actual radio, with the exception of the cabinet "fins" having been left out of the drawing, presumably for clarity's sake. To see both drawing pages, please click:
here and
Now back to our story....
5/5/98 -- The Silvertone arrived today. I had gotten the notice last Saturday from the Post office that it was here. The three day wait was almost unbearable. To back up a bit, a week and a half ago, on the Friday night AOL chat, a fellow collector had offered up a Silvertone he had rescued from the scrap heap. Opportunist that I am, I quickly said I would take it. Later I looked up the set in Stein's Radiomania, Volume 1. It was a model 6110, and the book value was quite high ($750 in black bakelite). But all he wanted was postage. Even later, when I checked back with him to be certain he knew what he was giving away, he said he did, and that he "didn't do Silvertones", and that it should be with someone who does. Well, I do.
I picked up the set and rushed home to unbox it. I had already been told it had a chip missing from the cabinet. It does, on the top rear. I'll devise a plan to deal with that later. First, let me describe the set to you. It is about the size of a shoebox, yet cylindrical in shape, with flat fins front and rear. The right end cap is the tuning dial, and below that is a large-ish on/off/volume knob. The owner had described it as a "Mix-master" flattened into a box. And yes, it does look like that. Also perhaps like a small Electro-Lux vacuum cleaner.
The complete radio after cleaning.
I noticed right away a very brittle, broken line cord and long-wire antenna entangled together.
As I lifted the set, I heard a rattling inside. My hopes were raised that the missing chip
might be inside! I rushed the set down to the workbench and began to open it. On the bottom,
there were three screws inside felt feet. I removed them, and the chassis came loose, but still
I couldn't open the set. Then I discovered the left end cap was loose. I pulled gently on it,
and to my surprise, it was held on only by a small rusty spring attached to it and the chassis.
I couldn't get my fingers in enough to get it off. Finally, I bothered to read the label on the
bottom. It told me to remove the tuning dial, depress the push-buttons, and slide the chassis
out. I removed the screw holding the tuning dial on, the dial popped off, and I easily slid the
chassis out. I set the cabinet aside, and studied the chassis.
The surface of the chassis is somewhat rusty. I found no sign of the missing chip, much to my dismay. The rattle was the result of two of the tubes having come loose during shipping. I reseated those two tubes, noting that of the 5 tubes, three were the original Silvertone brand. In the process, I verified the correct tubes were in each socket. 6K7, 6K7, 6J7, 1V, 25A6. The 6K7's were not Silvertone tubes. I inspected the pushbuttons. Of the six, four were labeled with Minneapolis stations! (The set was shipped to me from the east coast, I live in the Minneapolis metro area.) The other two were not legible. I removed the volume knob and set it aside with the cabinet. I tried gently to remove the pushbuttons, but had no luck. Setting the chassis aside for now, I went back to re-evaluate the cabinet.
The black bakelite cabinet is in reasonable shape, except for the chip. It basically is 3
pieces, the body and the end caps. The left end cap is perfect, with a nice shine still intact.
The main body is a little rougher, the shine gone completely from the top, the front and rear
fin areas dirty. It's hard to determine exactly how much shine is left on these areas. The dial
end cap is dirty, and the white paint from the dial numbering grooves is either missing or
dirt-filled. The large bakelite "screw" that held on the end cap is damaged around the slot
area from someone using a screwdriver over zealously. The key holding that "screw" to the
shaft was not original, and was too long, so the screw didn't seat into the dial. The slot was
damaged by someone trying to tighten it down. Inside, the license label is intact, but peeling
from the top surface, and slightly torn. The grill cloth is in good condition, but also
seperating due to the age of the glue. The label on the bottom is 90% intact, but
water-stained. It gives the model number as 6110, serial no. 693299. At this point, I decided
to give the cabinet a perfunctory cleaning. I removed the grill cloth and set it aside.
Left end cap, right end cap is the tuning dial.
My favorite cleaner is Westley's Clear Magic. I liberally sprayed it on the top and sides of the
cabinet, and let it soak. A brisk rubbing with a soft paper towel removed 90% of the dirt in
less than 5 minutes. This revealed a dozen or so paint spots, ranging in size from a pin point
to pea size. The Westley's didn't loosen these, so I turned to another chemical, Goof-off #2.
I soaked down the paint spots with this product, and removed them without much trouble. Another
round of Westley's, some good elbow grease, along with a soaking of the end caps. I invested
about 3 hours total cleaning the cabinet, including much time spent cleaning the fin areas with
Q-tips. All the cleaning did restore some of the shine, and now the cabinet is much better.
Now I can go to work on the chassis. Still need to deal with that quarter-sized chip, however.
Photo showing the chipped corner.
Stay tuned for more updates on this project. I've now obtained a schematic. Click here to view the Silvertone schematic. Beware, this is a large file.
Update, 6/23/98
I've now posted the correct schematic, thanks to my friend Sal. He located it in Riders and scanned it for me. This isn't the benign transformer powered set I thought it was. If you look at the new schematic, you will see the transformer is not an isolation type at all. One side of the AC line is tied directly to the chassis. I'll be using my isolation transformer on this set! The previous schematic, for a slightly different set, showed an isolated chassis. The other difference is that the antenna on this set is capacitor-coupled to the RF amp.
I've now ordered and received replacement capacitors for the set. This weekend, I hope to begin the electrical restoration. I did manage to fire up my Eico 666 tube tester and run all the tubes thru it. I'll post an update on the outcome of that testing soon. I apologize for the slow progress; I've been busy for the past 6 weeks cleaning up tornado damage.
Update, 9/14/2000 --- yes 2 years later!
While I've neglected this page, I haven't neglected the Silvertone. In response to a whole bunch of emails lately asking what's been happening with the set, I'm finally going to get off my duff and fill you in on the progress (or lack of!). More pictures of the progress will follow soon.
Back in late '98, I recapped the radio, and measured all the resistors. No resistors were horribly out of spec. The caps were ALL bad. This chassis had a 3 section electrolytic, mounted above the chassis in a cardboard can. I decided not to try to restuff the can, as it looked like I would end up destroying it while removing it. And I wanted the chassis to retain its' original appearance. So I simply clipped the leads below the cap and soldered modern miniature electrolytic in place below the chassis. The rest of the wax caps were replaced with modern poly caps as well. I also replaced the long wire antenna and cleaned the volume pot. Of the five tubes, one 6K7 had checked out bad. A Silvertone brand replacement was secured and installed.
The original line cord was brown, the radio case is black. I replaced the badly deteriorated line cord with a modern non-polarized black cord. The cord had no strain relief originally; I added a snug fitting rubber grommet to the exit hole. I also managed to remove the pushbuttons and clean them thoroughly. The chassis itself has a mottled, spotty, and even a bit rusty appearance. Because of the fragile nature of the coils and transformers, I decide not to attempt any kind of rigorous cleaning of the chassis. I only wiped it down with a rag and solvent to remove dust and loose dirt. This improved the chassis look greatly. The pictures at the bottom will show the completed chassis. The tuning cap was also given an air bath.
I fired up the freshly restored chassis on the iso-variac, it quickly came to life and pulled in stations all up and down the band. This set has no AGC or AVC, so reception is highly dependant on the antenna and signal strength. Satisfied that it was working correctly, I replaced the chassis into the still unrepaired cabinet. At this point I corrected the length of the key that held the tuning dial to the shaft. I buttoned it all up and tried it again. It still worked, and that is always a satisfying feeling. The stations even lined up perfectly with the dial calibrations!
Over the last year, I had made two unsuccessful attempts at repairing the damaged bakelite cabinet. I was finally ready to admit I needed help with this. More on that to follow.
Thanks for your patience. I promise it won't be another 2 years before the next update. Pics soon!
Update, 9/27/00 --- Dial restoration
I finally located a source I trust to restore the cabinet. The plan is to repair the chip, paint the repair area, blending the paint into the rest of the radio case, and clearcoat the entire cabinet afterwards. Before that, I needed to do something about the dial markings.
I used Goof-Off #2 and many toothpicks to remove all traces of the old gold paint (which I had thought was dirty white paint) from the dial markings. Then I used more toothpicks and painted in the dial markings carefully by hand. I cleaned off any mistakes once it dried, using my thumbnail. I also painted in the reference line on the cabinet. Here is a photo of the completed dial.
Photo showing the restored dial.
This week I'm going to package up the entire cabinet and ship it off UPS to the fellow who's going to do the repair work. I also discovered I have more work to do on the chassis; the pushbutton assembly needs cleaning and lubrication. More soon!
Update 11/18/00
Photo showing the restored tuner mechanism.
The cabinet got shipped off to California some weeks ago, and now it is in the queue for repair. I anxiously await its' return. I've spent the last few nights disassembling and rebuilding the push button mechanism. The buttons sit on fork shaped stamped metal shafts, which are held in the up position by springs. The center of the forks each push down on one of six seperate cams, locked into position by the tension applied by large bakelite screw on the end of the shaft. The cams are on a shaft that is coupled to the capacitor shaft by an insulating "spider". The pushbuttons were very stiff, and wouldn't reliably return to the up position. I took the entire assembly apart up to the spider, cleaned off the old lubricant (which was like glue after 61 years) and reassembled the entire mechanism. I fabricated a new black cardboard "mask" for the top surface. The mask simply hides the steel from the operator. I also fabricated a new cardboard cushion stop for the forks. This serves to soften the hard return and avoid that metal-on-metal "clunk" that would otherwise resound. After assembly, I lubricated the forks at their slide points with a white lubri-plate product. The buttons now operate smoothly and return nicely.
Front and Rear views of the completed chassis.
3/2/01 Flash -- the cabinet repairs are complete, and the result is amazing. The repair is nearly undetectable, and the entire cabinet has a beautiful new coat of shiny black paint. The radio looks beautiful. Joe at radiosphonos.com and his team did the cabinet work. Please visit his web site and let him know what a great job he did! Following are two shots of the completed cabinet. I now only need to assemble the radio and the project will be complete!
Two shots of the completed repairs.
This weekend I'll be gluing the grille cloth back into the cabinet, then assembling the radio. I still need to make some station call letter labels for the buttons. Watch this page for the wrap up very soon.
3/4/01 Today I installed the grille cloth. This was a tedious process. The last thing I wanted to do was to get glue on the exposed portion of the cloth. I ironed the cloth, dampening it first. I pressed it between two paper towels and ironed it for just a few seconds. Then I laid it flat to dry and cool. I used white glue and a fine brush to spread the glue onto the grille bars and the surrounding area. Carefully placing the cloth in, I had to get it right the first shot.
After letting it dry for a couple of hours, I was ready to re-install the chassis. That itself is quite a process. First I washed and installed the volume knob, then I depressed all six preset buttons. I inserted a piece of stiff wire thru the push-button assembly as per the instruction label. Then I slid the chassis slowly into the cabinet. Near the final position, I had to sneak a screwdriver in and depress the last three buttons individually to achieve the final chassis position. I then installed the three feet/screws that hold the chassis in place. Each has a well-worn felt pad on it. Next I put the tiny key in the keyway on the shaft and installed the tuning knob. Finally I installed the bakelite screw that holds the knob on and applies pressure to the preset mechanism. Lastly I made new station call letter tabs, (reproducing the original stations and adding two for the missing ones) and clear plastic covers for them. Here is the finished product!
6/6/01 Two weeks ago, at the Northland Antique Radio Club's (NARC) spring swap meet, RadioDaze, I entered the Silvertone in the contest. There really wasn't a category perfectly suited to this classic machine age design, so I entered it in the Art Deco category. That category technically did not include Bakelite sets, but it was the only one close. Maybe next year there will be a category for machine age sets.
As you can see, the radio did quite well. It took first place in the Art Deco category, and won the Peoples' Choice award as well. Now how do I top that next year?
On to the next project!
