[bridkarl]

I don’t get it either. It doesn’t seem necessary. 

 In any event I have this all complete. Just tried bringing it up on the variac but have no voltages - even filament. Checked the fuse I installed and it’s good. 

I need to check the tubes tomorrow. Fortunately I
have another unit of this model arriving today or tomorrow so I’ll have a set of spare tubes. Checked the rectifier just now and it tested good.

I just checked the power switch. With the switch pushed in - checking between the one lead on the condenser block and the other lead on the rectifier - pin 5 it looks like - I’m seeing no continuity. So it looks like the switch is bad.

Is this switch unique to this model or could I do a pull from another model? What would be the best way to by-pass the switch? Just put a switch in the cord ? I’m not sure how to clean this as it seems like a sealed switch - unless that round cover comes off?

[patrician56]

Regarding your question about the original power cord. Here is a photo of my 41-255 power cord. It was a brown plastic (rubber) cord molded with a gromet (strain relief) going into the chassis and a plug molded onto the other end.  I would think that the '41 and '42 models would be similar.

[bridkarl]

Thanks. In the 42-345 it seems like it was the same.
There was just a piece of rubber hose in there as an insulator when I got this so I ended up just opening up the hole and putting in a new 1/4 inch rubber grommet. 

Right now I’m just getting no voltage so I’m trying to diagnose that problem.

[bridkarl]

There was an earlier post by Ron about replacing power switches on radios with push buttons  - a problem I’m dealing with right now.
Just as an update to that - I think I found the identical part he describes still being sold at Lowes - I found it at the end of the electrical fittings aisle on the display with switches. I expect it’s in the same place at allLoees. 
The number is 427662 for $4.68. 

I still need to disassemble this to see if it’s the same but it seems identical. 

In the meantime I carefully bent two tabs underneath the switch cover. There’s a third tab but working with two is enough to get you access to the switch without more extensive removal of the entire push button assembly.

 That allowed me to spray the interior of the switch with De-Oxit Gold - wiping out the excess with a small pipe cleaner. After that I simply exercised the switch 20 or 30 times - which seems to latch correctly.
As I saw no evidence of physical damage or burning I’m hoping this is enough. Boring issue I realize but I thought an explanation might help before someone just cuts a switch off. Cleaning first seems a good idea and I haven’t seen a description of this anywhere.

This did nothing. Radio is still dead. I’ll wait for my replacement unit to arrive so I can check my wiring/repairs against an original unit and the schematic. This is the second or third time this has been recapped so there may have been errors introduced by previous owners I’ve missed. 

The next step after that is putting a jumper bypassing the switch and establish that the switch is truly dead. 
Which leads to a full replacement of the push button switch. Arghh.

[bridkarl]

I finally broke down and installed a switch to bypass the factory switch. That was indeed a bad switch with infinite resistance.

With the jumpered in switch ON the radio pulls .83 amps at 112 volts - but the radio is still totally dead. No filament voltages - absolutely nothing. Swapped out the rectifier tubes - nothing.

So the checking will continue. Back to Marcus and Levy to diagnose this unit.  If this was an AA5 radio I’d think a bad tube is killing it but this isn’t. My suspicion looking more closely is some short in the transformer wiring.  Under my loupe I’m seeing some really crummy wiring which I previously missed.

That said, I tested my parts unit - it appears to be working and has a working power switch. It’s seemingly in better shape than this other one.

I’ll recap this one - I’ll have one nice working unit in a nice case for me and eventually an average unit I can put on eBay or use for spares. 
SUCCESS!!!!

Got that recap done - so much easier the second time. Radio works great. 
AM broadcast and shortwave seems fine. I’ll check again this evening.
Just need to restring the dial cord and do some physical cleanup. And figure out how it gets into the case. It seems to be catching about 1/2 inch from the front on something.  I’ll let this run for ten hours or so on the bench while I do something else

[bridkarl]

Is there an easy way to get these coils out of the way so I can replace the two .05 caps underneath? Last time I just sort of loosened them and gradually wiggled them off the chassis.  Or is there a way to do this without moving the coils?

[RodB]

When you have access to one end of a cap or resistor you can cut or unsolder the accessible wire lead. Then twist the part (just keep spinning) until the other lead separates from the part. You can then use the coil method to install the new part.

[bridkarl]

Thanks. 

There’s absolutely no room in there to do any kind of twisting or bending. I just carefully removed the two aerial compensators over these parts and replaced both the .05 mfd caps and the 4.7k ohm resistors. Obviously using a soldering iron anywhere near those wax coils is sort of scary. I’ve noted the area in question on the attachment.

Everything is back in place and the radio works well so success. Back to checking the other resistors while I wait for my dial cord to arrive.

Any idea what this uses for pilot lamps? LEDs won’t work because of the metal shield on lamp assembly won’t work with the physical design of the led which has a rim.

[bridkarl]

I figured out this uses a 44 for the band indicator and 47 for the pilot lights. Replacing with GE1847 -a little dimmer but not hot and will be long lasting. The band indicator looks like a piece of plastic - surprised it isn’t burnt after 80 years from a 44 bulb.


Does anyone have a correct dial string diagram for this? Specifically I need to know how to string the cord for the dial indicator.
This has two strings. I successfully strung the one for the tuning knob. Easy enough once I used some PB blaster and loosened the nuts to remove the wheel on the tuning cap. I made it really tight since I figure eventually the cord will stretch with age and use.

With the other on the large wheel I’ve tried various combinations. Clockwise, counterclockwise, tuning cap fully closed, fully open. Wrapping the cord twice around the wheel.


 All that happens is the tuning cap just sticks in place and the cord lifts off the wheel. 
I found this diagram from the 42-350 which is said to be similar but it isn’t working.  One thinks this would be the easy part but no.

[bridkarl]

This is all up and running. 
Restoration notes: 
New caps throughout including PS caps, resistors checked and replaced as needed, replaced bad wiring, Bakelite block redone with safety caps, new dial cord, new polarized power cord with rubber grommet added in chassis,  added 1 amp fast blo fuse, case cleaned, patched hole in speaker and replaced all bulbs with GE1847 

Had it running for several hours. No apparent problems. Sounds fine. Receives well on AM with internal antenna.  Still needs an alignment but I need to fix my signal generator to do that. Job for later.