[vecher]

Picked this up when I was living in Chicago area. Only paid $25.00 for it. Not sure if these are Rare or very common.Looks like someone started to replace caps. Not a good job.. Radio does play but not great on SW band .. Here are some pictures..
[Image: http://i292.photobucket.com/albums/mm38/...lel8vg.jpg]
[Image: http://i292.photobucket.com/albums/mm38/...x7na2y.jpg]

[Image: http://i292.photobucket.com/albums/mm38/...mn4ciq.jpg]

Cabinet is not that great. Speaker is perfect looks like it was redone.. looks like it has a small bias cell 1.5 volts that is probably no good.

Did the cabinet have any markings on front to tell what controls were?

My guess is someone started this and maybe lost interest??

Skip...

[Arran]

 There isn't anything wrong with Sprague Orange Drops in and of itself, but the installation was rather sloppy, the electrolytic placement seems just as bad. I would bet that whomever did the work probably just clipped the old caps out and tacked the leads of the new ones onto the old terminals without doing much else, so they will probably fall off within a few years. You could probably go in there with a soldering gun and remove most of them within 10 minutes. As for the bias cell, that really has to be there for the set to work properly, especially if it's on wiper of the volume control, if you rewire the holder so the polarity is reversed you can use a modern watch battery in it's place, or use the old cell as an adapter for the new watch battery.
Regards
Arran

[Radioroslyn]

Hi Skip
Just got your message will take a look.

Terry

[vecher]

Terry, OK thanks.. I will redo the Capacitors. and Check the dog bone resistors and replace anyway,in fact I will check all resistors. it seems that they used a lot of high value ones 47 Meg, 20 Meg, 56 Meg, 100 meg , 560 Meg??? I know I don't have values that high?? Do they make them??

Skip...

[vecher]

Ran into a problem checking the resistors
EX: Here is a picture of part of schematic..
[Image: http://i292.photobucket.com/albums/mm38/...fovfvb.jpg]

Part number 33134 say's I think 100 M ohms. However when measured it reads 100 K ohms.

Here is part list..
[Image: http://i292.photobucket.com/albums/mm38/...4tdplu.jpg]

the part list say's 100 M ohms.. Does the M mean kilo ohms??? This is from 1937..

All resistors that I thought was Meg ohms all measure K ohms..

Very confusing.. Any thoughts??

Skip...

[Warren]

what does the 560m resistor above it on the schematic measure? Does your meter say 560 k or 560 m?

[jerryhawthorne]

Skip, when it says "M" that relates in today's talk as "K". You will notice on the parts list you posted a "1 MEG", that is today talk as 1 Meg.
Jerry

[mikethedruid]

Another thought on the bias cell. There appears to be plenty of room under that chassis to install a single AAA cell holder, which would do the job nicely, last about as long as the shelf life of the battery used, and be easy to find when replacement becomes necessary. I think this radio must have been gone through back in the 1980s or 90s, from the look of the orange drops, and the electrolytics. The orange drops were very good condensers in their day, just a bit grunganous looking when used to replace old paper tubular caps, but that was what was commonly available in a lot of electronics shops for hobby and replacement use back before the internet. Be thankful, fellows, the internet has made the hobby of keeping the old radios alive a lot easier.

[Arran]

Ran into a problem checking the resistors
EX:  Here is a picture of part of schematic..
[Image: http://i292.photobucket.com/albums/mm38/...fovfvb.jpg]

Part number 33134 say's I think 100 M ohms.  However when measured it reads 100 K ohms.

Here is part list..
[Image: http://i292.photobucket.com/albums/mm38/...4tdplu.jpg]

the part list say's 100 M ohms..  Does the M mean kilo ohms???  This is from 1937..

All resistors that I thought was Meg ohms all measure K ohms..

Very confusing..  Any thoughts??

Skip...

 The "M" after each resistor value stands for Mill, or latin for one thousand, like millennium. On those older schematics the draftsmen sometimes used "M" whilst others would used "K", notice that the one million ohm resistor above the bias cell says 1 meg ohm. If the 100M resisistor tests as 100,000 ohms that's great, it means that it does not need to be replaced.
  Regarding the bias cell, another way around those is to redesign the circuit, like replace the bias cell and the 1 meg resistor with a 10 meg ohm one, but connect the cathode of the first audio tube to B-, but try a watch battery there first to compare.
Regards
Arran

[vecher]

Thanks All, All the resistors that I checked were measuring K ohms.. So that makes since .. I will go back and check values again. Thanks for the info on the bias cell.. That would have been my next question.. You guys are good.. answering my question before I asked it..

The big blue Electrolytic caps I think are replacing the Cans.. But looks like the cans are still hooked up also..

Skip...

[vecher]

Well checked the resistors most are Ok.. I will replace the Dogbone's however.. But found a new problem See picture...
[Image: http://i292.photobucket.com/albums/mm38/...hr2msq.jpg]

Wires from IF can are missing insulation.. And a really mess adding the Electrolytic

[Image: http://i292.photobucket.com/albums/mm38/...iviimr.jpg]

Looks like they added 2 caps in Parallel with existing Can .. The Can was 12 Uf at 450 volts.. They added an additional 147 Uf at 450 volts.. ???? Maybe to get rid of Hum.. or maybe not knowing what they were doing...

Anyway a lot of work cut out here..

Skip...

[Arran]

 If the resistors are in good condition and measure within 10% (some go up to 20%) I would leave them as is even if they are of the dogbone style. Believe it or not some dogbone BED coded resistors were quite stable, most were not, but in any even if they haven't drifted in value after all this time they likely never will.
 Regarding the leads into the IF cans, by all means replace those, the primaries often carry near or full B+ voltage so the wires shorting to the chassis will not be a happy experience. One part that you may want to take a closer look at is that square molded capacitor connected to one of those rotted IF can leads, it says "Micamold" on it, it may be a mica cap or it may be a small paper cap, check the parts list to see what value it is.
  As for the electrolytics, don't even bother trying to figure out the state of mind of whomever put those in there, just take them out, test them, and if good hook them up the way the factory intended, or order some new name brand radial lead jobs to restuff the original cans. The way they have them mounted is just moronic, the connections are made in mid air to some original wiring, that's a big no no given the voltages they handle. It would not surprise me if the reason that the set hummed was due to a wiring error, particularly on the negative side of those filter caps, sometimes the chassis is not the most negative point in the set.
Regards
Arran

[codefox1]

If you have the schematic, you should replace capacitors with close to original values (a little higher is OK, but no real advantage in going much higher, and can actually cause problems.) Those replaced caps might be OK, but don't know how long ago repairs were made. I'd replace all of 'em and do it neatly with shrink wrap/spaghetti insulation. As for the resistors, for the pennies involved consider replacing all of them as many may have drifted up or become noisy. Certainly the decals disappeared when someone refinished the cabinet. Dunno where to get specialized decals, maybe someone else does.

[vecher]

Ok Next problem .. Does anyone know how to remove the IF Cans?? See picture..

[Image: http://i292.photobucket.com/albums/mm38/...mlhiri.jpg]

Looks like you could compress the tabs but I was afraid of breaking them .. Any thoughts??

Skip...

[jerryhawthorne]

Skip, if you feel the wires insulation is compromised at the entry point through the chassis for a potential short to ground, I would remove the wires in question from their external attachment and sleeve them with a bit of heat shrink at the entry point, don't push it in too far, just enough to clear the entry. Heaven knows what you might hit (a lot of small wires etc. if you go way in). A 1/4" piece should work fine. Reconnect the wire end back where it came from. I hate digging into the depths of IF cans!
Jerry