The PHILCO Phorum
1933 60L Restoration - Printable Version

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RE: 1933 60L Restoration - morzh - 11-04-2018

No this is the sch I had when tackling mine.
The sch shows the cap of 0.18uF which is physically a backelite with the two caps, two of the ends connected to the GND screw, and two separately connected with that bare wire (middle and left), the flex 200 ohm resistor going from the left pin to GND screw terminal.
It is in perfect agreement with the schematic.

RE: 1933 60L Restoration - klondike98 - 11-04-2018

OK...so there are many versions of the 60 schematic and they are nicely documented by Ron at the following LINK.

You may have Run 3, which has the extra 5th lead coming from cap can #20 that connects to cap #8.

If you look at Run 2, they added a .02uF paper cap and then in Run 3 incorporated that paper cap into the larger condenser can.

RE: 1933 60L Restoration - Greggshere - 11-04-2018

Awesome, thank you both!

RE: 1933 60L Restoration - Radioroslyn - 11-05-2018

>The sch shows the cap of 0.18uF which is physically a bakelite with the two caps, two of the ends connected to the GND screw

Just to clear up perhaps a little confusion I'm not sure why but Philco back in the late '20s used .09mfd caps and continued to use them in to the '30s. It's a non standard value. That's how your model 60 has a .18mfd it's two .09's in parallel. Perfectly fine to use a couple of .1mfd cap to replace the .18mfd.

RE: 1933 60L Restoration - Greggshere - 11-05-2018

Thanks Terry, Bob and Mike, yes you have all cleared it up for me, and I do indeed have the Run 3 Chassis. That schematic you posted is what I have and is why I was confused. Being new to this hobby I have a lot to learn, and I appreciate both your patience and assistance. I bought my schematic off of Steve's Antique Technology and did not realize there had been a schematic / parts change (run 3). All of you have helped tremendously.

RE: 1933 60L Restoration - morzh - 11-05-2018

Yes, 0.1uF is what I used. These values most times are not critical.

RE: 1933 60L Restoration - morzh - 11-05-2018

https://www.mouser.com/ProductDetail/Cornell-Dubilier-CDE/930C4P18K-F?qs=sGAEpiMZZMsh%252b1woXyUXj4g0ZAJG5DeW2brfg4UM9lI%3d

Just to clear.....0.18uF is also a standard value today (0.09uF is not) and is stock in Mouser (the link above).

However this i rarely needed in radios and 0.1uF is a very popular value so I use two of 0.1uF instead.

RE: 1933 60L Restoration - Arran - 11-07-2018

I don't know if this is true or not but I remember reading somewhere that paper capacitors of the 1930s and 40s , had a tolerance of + or - 20%, which may be optimistic. So if the schematic calls for a .09 mf cap use a .1 mf, since a modern film cap is probably closer to spec then the original.
Regards
Arran

RE: 1933 60L Restoration - Greggshere - 11-07-2018

I did use the .1 caps in that Bakelite condenser. Also, on the AC power in condenser block I installed a .015 safety cap. and per the service update I was going to add a second .015 for the other line, but I couldn’t physically fit two .015 safety caps. in it. I used a physically smaller .01 safety cap in there with the .015. Should that work ok for the hum reduction? Will having two different values on the lines be an issue?

Also, below is a photo of the chassis before I started working on it of a blue .04mF capacitor that was in this chassis and I have not done anything with it yet. I'm trying to restore this as close to original as possible, which is why I have re-stuffed all of the bakelite blocks, the electrolytic cans and the condenser filter block. This puppy appears to be an add on someone did in an attempt to repair an issue. The electrolytics had also been by-passed with some old big loose caps. At least one of the cans was there and I got another one on Ebay cheap that matched.

Anyway, can anybody provide a photo/diagram/etc. that shows what this chassis should look like without that cap and resistor (wired in parallel to the cap)? If it was an attempt at some repair, I need to determine what is most likely defective, so I can correct it. The cap is going between the 6A7 and the wire that is going down into the top of the Oscillator Transformer can. I haven't removed that yet from the chassis. Any help would be great.