[murf]

Hi guy's,
Picked up a nice looking model 29 the other day.
Person that had it inherited it from her dad who restored it 15 years ago.
After removing the chassis and looking it over,I realized that he had made some mods to the electrolitics.
On the schematics it shows number 61 electrolitic as a single 6 mfd.
The can for this one is marked as a philco 30-2028a with 2 terminals plus a ground terminal.
The cap he installed is a 20 mfd 450 volt on this one.

The other Elect Cap #64 is supposed to have two 8 mfd caps and a 10 mfd cap.
The can for this one is a mallory type FP. It is marked as having two 20mfd x 450 volt caps, but the schematics list two 8 mfd caps and a 10 mfd cap.

The cap he installed for this one is a single 100 uf 25 volt.
Would anyone at the forum have a good clear closeup picture of the underside of the chassis showing the original electrolitics in place?
By the way, the radio barely played when I tried it.
I would like to bring it back to being close to the schematic if possible.
I am at a loss as how to wire in new electrolitics on this one.
I know he did not do it right.
Label inside the cabinet says model 29, 45
How can I tell which model I have? No markings on the chassis, but tube count and numbers are the same for both.
Thanks

[Arran]

Here is a link to some Philco model 29 data at one of my favorite radio sites:

http://www.nostalgiaair.org/PagesByModel...013181.pdf

There is even a parts location diagram for under the chassis, though it does not show wiring, as usual with Philco diagrams. It looks like there are two 8 mf caps and one 10mf cap inside part #64 with the negative end connected to the transformer center tap, they appear to be in the same can. One 8mf has it's positive connected to a filter choke and the input side of the field coil. The other 8mf has it's positive end connected to the output side of the field coil and one end of the primary for the output transformer, the screen grid of the #42 output tube, and a 5000 ohm resistor. The 10mf cap has it's negative end connected to the center tap of the power transformer, the same as the two 8mf caps, and it's positive end connected to chassis ground. The 6 mf cap is called part #61 and is connected between the output side of the filter choke and chassis ground.
All of these caps are mounted in two cans on top of the chassis, nothing underneath other then the wiring, and none can be replaced by a 100 mf 25 volt cap, the strange part is that they are on the opposite end from the power transformer and #80 rectifier. The two 22 mf caps could be used to replace the two 8mf units, or one could be used to replace one 8mf unit and the 10 mf unit.
One thing that you will not like about this set is that it appears to use some form of early circuit board, like an early 30s GE or RCA, this will have to be rebuilt with new capacitors and resistors most likely. The good news is that it looks like all of the parts are facing the bottom of the chassis so you may not have to remove it to replace the caps and resistors mounted to it.
Regards
Arran

[Ron Ramirez]

...and here's some links to Model 29 info at one of my favorite websites:

http://www.philcoradio.com/gallery/1935a.htm#l <--- I actually have one of these, I need to get it photographed and put in the Gallery to replace this poor illustration.

http://www.philcoradio.com/gallery/1935a.htm#m

http://www.philcoradio.com/gallery/1935b.htm#c

http://www.philcoradio.com/gallery/1935c.htm#e

Model 45:

http://www.philcoradio.com/gallery/1935a.htm#u

http://www.philcoradio.com/gallery/1935a.htm#v

http://www.philcoradio.com/gallery/1935c.htm#i

Quick way to tell the difference: Model 29 has a shadowmeter; Model 45 does not.

[murf]

Thanks for the info guy's.
Will give me a place to start.

[Glenn Roberts]

Nice!! Great find!

[TA Forbes]

There are several schools of thought about replacing the electrolytic filter caps in the power supply circuitry. Many restorers believe that the biggest considerations for replacing electrolytics are only cost and size of the replacement cap. What I mean by this is that they see no problem with larger cap values, as long as they physically fit.

Some restorers limit this to no more than 100% over the original value.

It is important to consider that the larger the electrolytic value in microfarads, the larger hit your rectifier will take until the caps are fully charged. ONCE charged, however, no difference.

Personally, I like keeping it close to the original value. Maybe a couple of mFd higher, NEVER lower.

[murf]

Great info guy's,
Without getting too technical, I want to get the electrolitics and wire them into the correct components.
With having the original components basturdized, I am looking for an easy way to wire in the new ones.
The schematics are not making alot of sense to me if I can't relate them back to the chassis, due to someones shortcuts.
I will try taking Aaran's verbal description and using my highlighter, I will try to trace everything back to where it belongs.
Be patient please as I am still learning.

[Ron Ramirez]

So, Murf...don't leave us in suspense...which model do you have, and is it 29 or 45?

[Steve Davis]

"It is important to consider that the larger the electrolytic value in microfarads, the larger hit your rectifier will take until the caps are fully charged. ONCE charged, however, no difference."

Actually, the rectifier will take a hit once every cycle. Think of it as butting your head against a wall 120 times a second. Would you rather the wall be padded or bare concrete?

Steve

[Arran]

I know that some say that using larger value caps is hard on the rectifier tube but I haven't really noticed whether they wear out quicker or not. In the clock radio next to my bed I used a pair of 160 mf photoflash capacitors and it's been in use for years. The 35W4 rectifier tube did die but it was because the 50C5 was loose in it's socket and making intermittent contact, but it was playing for at least 3 hours a day for 5 years prior to that. In this case they used a 25 volt cap in place of a 450 volt one so the capacity is really a moot point.
Regards
Arran

[murf]

Ok guy's,
Replaced 2 of the electrolitics with the proper value caps,and it now works like new.
The previous owner did a really nice jobe when he re-capped it.
Removed the circuit boards and did it right. Replaced the resistors too.
Very nice clean job.
Of course once I replaced the tuning condensor grommets and installed the chassis back in the cabinet, the bulb burned out for the shadow meter.
Haven't looked at it yet, but I think I can replace it without removing the chassis.
THink I will put it on CL tonight for a couple hundo's and see if anyone bites.
It was re-laquered quite a few years ago and still looks real nice.
Will be bring home a Grunow 835 and another Coronado 2CM tomorrow.
Again, thanks for the input.
murf

[murf]

Here[Image: http://i1161.photobucket.com/albums/q509...xfront.jpg] is the 29x sitting pretty and working awesome.

[Arran]

If the party that you got this set from gave this to you as a gift I would not recommend posting it for sale on craigslist, at least not right now. In fact it's my policy to either keep or trade radios that I got as a gift since I usually know the people who give them to me and I don't wish to offend them if they should run across other radios or parts. If you did actually buy this model 29 then it isn't an issue but just mentioning the craigslist name creates an image of sleaze with some people. One thing that would net a better price, if the cabinet was indeed refinished with lacquer, would be to take some tone spray to the solid wood portions and get rid of the blond look.
Regards
Arran

[murf]

Hi Aaran,
Whatever made you think it was a gift?
Purchased it from a woman on CL who got it from her dad.
Just bought it to flip.
Radios works very nicely. The previous owner did a nice job when re-capping it.
He replaced everything.
Don't think I want to re-finish it though.
Maybe someone else will like the color.
Thanks