[murf]

Hi Guy's,
Have a question on my 40-190 that I am trying to resurrect.
SOmeone in the past has replaced the electrolitics in this chassis, which meant a little re-wiring to eliminate the cans.
Question is, the dogbone resistor connected in to one of the electrolitics has really faded colors which makes it hard to determine correct value. Might be blu or green with brown or red end and dot.
If I disconnect one end and measure with my ohm meter it reads .6 k ohm. Looks like probably a 2 watt resistor.
Looking at the parts list I see nothing around that value. Nothing over 1 watt.
Probably not the original I would guess.
Any suggestions?
murf

[Warren]

Have you tried to find that resistor on the schematic? Find it there and the schematic should tell you what value it is.

[murf]

Tried to track it down on the schematic, but due to the previous work done and moving and re-wiring of various components, I found it a bit of a challenge.
Suppose I could trace the wiring back to the tube pins, but the tube sockets are buried pretty good.

[DeckApe]

Can you provide us with a photo for geographic chassis reference?

[DeckApe]

Okay, here we go. Photos by murf:

[Image: http://i261.photobucket.com/albums/ii66/...-190-3.jpg]
[Image: http://i261.photobucket.com/albums/ii66/...-190-2.jpg]
[Image: http://i261.photobucket.com/albums/ii66/...-190-1.jpg]

That looks to be tied in to the 12uF e-cap... I'd guess it is a replacement; I don't remember dragging anything like that out from under mine, and since all my caps were stamped "PHILCO" I'm assuming it was all original. I also can't find anything of the sort on the schematic. *added thought* Okay, now that I've had my coffee and realized I'm looking at the wrong end of the capacitor, that looks to be dropped in between the blue-white wire from the field coil to the positive end of the e-cap.

What speaker do you have? The stock 36-1479, or a sub?

[Mondial]

Looks like someone did a lot of mods to that radio. I see a pair of silicon diode rectifiers bridged across the 84 rectifier tube socket.

Perhaps this is why there was no 84 tube present in the radio, as it was bypassed with the rectifier diodes and the tube was then not needed.

If that resistor does not appear on the schematic, the maybe someone added it to reduce the higher B+ produced by the silicon rectifiers compared to the stock 84 tube.

[murf]

I am thinking I might be better to look for another chassis to restore.
This one has been modified to the point where the schematics are of no value.
I noticed a 41 series on ebay.
Looks the same, different tube lineup.
Would probably fit the cabinet. Has the speaker included.
If anyone knows of a 40-190 chassis available, let me know.
Otherwise, any suggestions would be appreciated.
murf

[DeckApe]

Murf--keep your eyes peeled for a 40-180 or a 40-185 chassis too. They're the same chassis (well, the 180 is a 7-tube, but small matter) and will fit everything. (I'm flying a 180 in my 190 cabinet.) If you can find one that hasn't been heavily modified to start with, then I think putting the 40-190 back together will be easier afterward.

That resistor is on the positive side of the capacitor, where my copy of the schematic shows there shouldn't be one at all. I'm guessing it's some form of ballast. *edit* And since it's not tied to the rectifier socket (it should be), I'd agree it's tied into the rectifier bypass job.

Anyway, 40-180 chassis are out there, and will fit your cabinet perfectly (and once you've restored it, you have a pretty good road map to put your 40-190 back in vintage condition).

[murf]

I am looking as we speak.
Would be nice to find a 190 so that I would have a good reference to putting this hosed up mess back where it belongs.
Thanks

[DeckApe]

185 is electrically the same; the 180 is only missing one tube (the rectifier corner is unchanged). And there are a lot more 180s out there... just sayin'.

[murf]

There is a 41-250 chassis on fleabay which would fit as well.
Not sure about the speaker though.
This is from a table radio instead of a console.
I think the 41-350 uses an 8 inch speaker.

[37silverstreak]

Hey Murf,
Looking at my riders for the 40-190 the only big wattage resistor I see is part number 60 which is a 1 watt 150 ohm resistor which would be brown-green-brown. It connects directly to the negative of one of the filter caps and the center tap of the plate winding of the power transformer. hope this helps.
Kevin

[murf]

That was my guess too.
What would make a person want to completely change the power supply section of a radio.
Why not keep it original?
Makes me think there was a problem that could not be fixed the conventional way and he went to all this extra work just to bypass the original problem and make it work.

[Mondial]

The only reason I can think of for adding the diodes is that the owner did not have an 84 tube so he replaced it with the silicon diodes he had. Its a fairly common mod.

You can easily remove the diodes and just restore it to the original schematic using the 84 rectifier.

In any case, If you presently have around 180V of B+ then the power supply is working and likely is not the problem with the radio not playing.

[BrendaAnnD]

If the mod was done, say, 30 or 40 years ago, he may have had no recourse. 84's were long out of production, and there was no internet to go look for NOS or used ones. One does what one must to get something working.