This is a
Grunow model 750 also known
as the "World Cruiser" from 1937. The tube compliment consists of
6F7, 75, 42, 76 and an 80. It has four bands covering 550 kcs. to
21 mcs. with no gaps. This is a real performer with the tuned RF
(Click on the images for a larger
is an RCA model R-70 from 1933. It is a seven tube superhet with
three 58's, two 56's, a 47 and an 80. It is BC only with RF
I picked this up at a swap meet in Henderson, Kentucky in 1994.
cabinet was in pretty good shape. I only needed to remove the top
coats of lacquer, touch up the accents and reapply about four coats of
new clear gloss lacquer, sanding after each coat. The brass
had turned black, so I removed it, cleaned it with Ajax, polished it
with Brasso then put it in a pie pan with some
vinegar and heated it in the oven at 250 degrees for about 30
minutes. After removing from the oven, I buffed it to bring
out the highlights then coated it with two thin coats of clear mat
before reinstalling. This technique usually works on most old
brass parts to give it a nice aged patina. The dial scale was
another story though. Made of paper, it had been exposed to water
at some time and had several stains on it. It was also warped and
had a piece missing. I was able to drill out the tiny rivets that
held it to the backplate and make a copy of it onto white paper with a
copy machine. I then
removed the staining and other defects with Whiteout then made a copy
of this onto tan colored stiff card stock. After carefully
cutting it out, I soaked it in some strong tea to give it an almost
original color. I then dried it thoroughly, punched out the
mounting holes and apply two thin coats of clear mat lacquer. I
remounted it with 4-40 hardware. The whole dial now looks like
new. I was able to save
the original grill
cloth by removing it, washing then stretching it onto a new cardboard
frame I had made. I then reinstalled it behind the grill.
You should always try to save the original grill cloth. Yes, I
have replaced them with reproductions, but only as a last resort.
I can always tell a repro. when I see one.
The chassis had those metal cans on the underside that contained
multiple capacitors, which of course, had to be replaced. I
removed each one and rebuilt it with new caps before reinstalling
it. I had a bad volume control which I had to replace.
Luckily, I had a salvaged one that was close in resistance and
taper. The 47 was the only tube I had to replace. After
realigning the IF, it seemed to work very well except for the
AGC. It has none! I have several sets with no AGC, but I
don't listen to them, I just display them. But, with this set, I
wanted to make it an often used one. The lack of AGC is very
annoying, so I played around with adding my own. I know, never do
this, but I was able to come up with a circuit that used only one
resistor, one diode and one capacitor. I will show you how to do
this someday. The circuit worked so well, I left it in the set,
at least for now. Shame on me...
This radio sets in the foyer and is the first thing you see when you
enter our house. It is my favorite radio.
I purchased this one at an old radio swap
meet in northern Indiana the spring of 1999.
When I first brought this one home, the cabinet looked pretty
bad. There was veneer missing from the top and grill area.
There was a one-inch chunk of wood gouged out of the top corner.
I am not sure, but the band switch knob might be a replacement. I
stripped the finish completely, replaced the missing veneer and
the other damaged wood areas. My wife repainted the black
accents. Finally, I applied some toner and six coats of clear
gloss lacquer. I was able to save the original grill cloth.
As for the chassis, I replaced the 6A7 that was very weak, then
replaced all of the suspect capacitors and checked resistors for out of
tolerance. After bringing it up on a variac, it was dead.
After a lengthly bout of troubleshooting, I had found an open IF
transformer and two open RF coils in the band switch section. I
was able to repair the broken winding on the IF rather easily, however,
the band switch coils were another story. There was what appeared
to be corrosion on the coils, possibly from moisture, which had turned
patches of the windings into a green mass. Removing the coils
from the band switch was not a job for the faint-hearted. It was
as though the set was built on an assembly line and the band switch was
the first part installed with everything else added on around it!
After a lot of work removing the coils, I was
able to count the number of turns and rewind them with the same size
wire. After this, it came to life. All the work on this one
had payed off. The dial tracked very well on all bands and the IF
just needed a touch up. Not only is this a sensitive set but it
really has a great sound. As you can see from the picture, it is
a big table set but it fits nicely on my night stand.
Everyone's collection would not be complete without an Atwater
Kent. The is the AK model 55C in a lowboy cabinet. It is a
TRF set from 1929 and has two 24's, two 27's, two 45's and an 80.
Atwater Kent had their consoles built by fine furniture makers such as
Red Lion, Kiel and Pooley. I haven't been able to identify the
cabinet maker, so far. If someone does, please let me know.
I bought this in 1992 from a local antique dealer. Usually, I
don't buy from antique stores, but I couldn't pass this one up. I
just liked the look of it. It reminded me of a similar set I had
dragged home when I was a kid.
This turned out to be one of the most difficult restorations I have
been involved in.
The cabinet had water damage from the floor up to the top of the
spindle legs. Part of the wood trim pieces were missing.
The grill cloth was missing and the wood grill was broken with half of
it gone as well. The top looked like it was used to crack walnuts
on and one side was faded from, what looked like, sun exposure.
hardest part was making a new grill. All I had was half of the
original. I began by tracing an outline of what I had, then
flipping it to get a mirror image for the missing half. With this
as a pattern, I cut out a new one from one quarter inch plywood.
I painted the inside edges black and stained the front to match the
rest of the cabinet. Fortunately, there was a scrap of the
original grill cloth left on the inside of the cabinet. I used it
to find a reproduction from Antique
Radio Grille Cloth Headquarters that matched pretty well. I
made new trim pieces from cross sections of dowel rods and glued them
in place. I was able to restore the legs and sun-faded side by
removing all of the old finish then adding a combination of stain and
toner to get the original look. As it turned out, the top was
solid wood with no veneer so sanding down the scratches and gouges was
no problem. Again, several coats of lacquer provided the final
The chassis was rather clean on this one with practically no
rust. I have seen other 55C's and they all looked good
too. Atwater Kent was known for their quality of
parts. They could make bakelite parts with such detail that
they were amazing for their time.
Upon first checking, I found both 45's to be rather weak and needed to
be replaced. As you know, these are not cheap! A matched
pair of 45's sell for more than what I paid for the whole radio!
I happen to have two NOS GE 45's that I reluctantly installed in
it. After replacing the usual caps and one resistor, I powered
it up on my variac just to learn that I needed to do more
troubleshooting. I found one of the RF coils open which was an
easy fix but further investigation found a problem which, as it turns
out, is common with AK 55's. The interstage audio coupling
transformer was open. This is a real bear to repair because the
transformer is encapsulated in a black tar-like substance within a
metal can. The only thing you can do is carefully remove the unit
and heat it in an oven, about 300 degrees for 10 to 15 minutes or
until the tar softens enough to pull the mess out of the can.
Once out, I used a heat gun to remove enough tar to find that the
transformer was unrepairable. I should have just discarded it
when I got it out. I found an almost exact replacement for it at Play Things Of Past. I
installed it in the can and packed it with styrofoam peanuts. At
least it won't be a problem to get it open again if it ever
fails. You can remelt the tar and put it back in if you want the
ultimate in authenticity but I have heard the potted transformers like
these fail because of the sulfur in the tar that corrodes the copper
windings. See links for other sources
for a replacement transformer. If you still can't find one, you
might check out what Norman Chamberlain has as a solution by clicking here.
This was the last problem
other than tightening the
metal drive belt on the tuning mechanism.
For a TRF,
this set works very well.
Almost as good as a superhet
without all the squeals. The only thing I don't like is
the lack of AGC. As a collector, you must have at least one
console in your living room so I chose this one. Here, you can
see it fits in very well with our "old maid" decor (notice the doily on
This is a RCA B-411 tube portable radio from 1951. It has four
tubes, 1R5, 1T4, 1S5 and a 3S4. It operates form one "D" cell and
a 67.5 volt "B" battery. The case is made of a plastic called
"Santay" which has a beautiful swirly look.
I have three of these, but this is the only one I have restored.
This was an eBay purchase about seven years ago for $17. The case
was in pretty good shape with no cracks and the dial knob still had the
chrome trim intact. This is a common problem with these.
The metallic backing comes off easily and you will see black splotches
in it's place. The RCA Victor raised logo on the front was
originally chromed but is usually worn off on every B-411 you
see. I believe this is caused by rubbing on the leather
have two of the carrying cases with some cracking of the leather on
The chassis only needed a cleaning plus I had to replace a 100 mfd.
capacitor. I rebuilt the 67.5 volt battery with seven carbon-zinc
nine volt batteries I purchased at Walgreens for 39 cents each.
This, along with a new alkaline "D" cell, brought it to life.
Since these have quick heating filaments, they turn on almost
immediately just like a transistor set. Everyone that first sees
this radio thinks it is transistor, especially when they pick it up and
turn it on. They are amazed when I show them the insides!
construction, lots more coming soon!
This is a Raytheon-Belmont Model 7DX21 television from 1948. It
has 18 tubes plus a 7 inch picture tube. This set was also sold
as a kit by Heathkit for a short period.
A good friend gave this set to me. The cabinet looked pretty good
with the usual scratches on top as you would expect on a set this
The chassis was in good shape too, but it needed a lot of work
electrically. First of all, this set doesn't have a power
transformer so the tube filaments are wired in series-parallel with a
ballast tube dropping part of the voltage. On most sets like
this, the ballast is usually bad. This one had several sections
open. I was able to dissemble it and replace the "toaster wire"
like resistors with conventional power units. It was tight, but I
got them to fit. I replaced the selenium rectifiers with 1N4007's
along with the filter capacitors. The set was full of old paper
and wax capacitors, all of which I decided to replace. Two of
them were 5,000 volt rating which I finally found replacements for on
eBay. I cleaned all of the controls. Upon checking, about
12 out of the 18 tubes were either weak or not usable. Since
these were inexpensive, I replaced all of the suspect ones. I had
no way to properly check the CRT, so I just hoped it was OK. When
I first powered it up with a variac, I could get a raster and some snow
but no picture even when connected to our local cable. It turns
out the turret tuner needed further work. I had to get inside it
and clean the contacts and try to realign the channels. Slowly, I
begin to get a picture. With further realignment of the IF, I had
a decent picture with good sound. The old CRT was in surprisingly
On the cabinet, I had to dissemble the front bezel around the CRT and
clean under it. I was able to remove part of the original finish
and sand out all of the scratches on the top and sides.
Amazingly, the original decals by the knobs, were still intact.
After the final sanding and going over the cabinet with 0000 steel
wool, I applied 4 coats of clear gloss lacquer while using the steel
wool between each coat. I used bee's wax to get the final
I really like this set, not only for it's looks, but because it's
fairly small and lightweight because of the lack of power transformer.
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© 2006 ~ Michael R.
Starcher ~ All Rights