[PhilcoPhan1936]

I'm starting to check out the 1st of my 1933-34 89Bs. A question on the Cap block: The Philco Repair Bench site states the voltages of the cap block to be 2000/1200/1200/2000/2000 volt rated caps . Is this really necessary? Or can lower rated caps go in there

[Ron Ramirez]

No, you can use 600 or 630 volt rated film caps as replacements. There are some that could be replaced with 400 or even 200 volt caps, but 600/630 volt film has become the standard among collectors - they are cheap, easily available, and generally small enough to fit inside bakelite blocks easily.

[PhilcoPhan1936]

Thanks Ron. I think I have those on hand, and I can get them locally if needed.

[morzh]

There is usually only one cap in radios that is intentionally rated about 1000V. This is the one that goes from the plate of the output tube (in case of CLASS A, a single ended output) driving the output transformer to the GND.
The reason is, if unplugged while in operation, the speaker creates disruption to the current that creates overvoltage, that when reflected back to the primary can reach into some pretty high numbers, even over 1kV.
In normal operation the voltage there is no higher than the B+.

If the speaker is soldered it, there is no way for it to be unplugged. And then, even with the plugged speaker, it is unlikely.

So, personally, I use 600V-rated caps in that circuit.
The rest of the caps also d not need to be rated any higher than that.

[Ron Ramirez]

Split into its own topic per Da Boss Sam.

[PhilcoPhan1936]

Thanks Ron. Sorry about hijacking earlier. Another couple questions:

1. What would be the value of the cap on the tone control? I looked up the part No. on Philco Repair bench and it wasn't listed. It's a 1-position click switch.

2. Are 450v rated electrolytics OK to use?

This is my earliest radio to work on thus far. I'm used to later 30s Philcos. I noticed in the paperwork it's not as well documented as far as parts lists for the earlier 30's models.

Thanks for any info.

I'm sure I'll have more as I work on it. I actually have 2 copies of this. The idea is to hopefully restore both and sell one.

[PhilcoPhan1936]

For those curious, here's some pics of the 2 I have. The 1st one I'm working on was picked up at my 1st ever radio swap meet in October 2015, along with a Philco 604C and a 59C.
Here they are on my bench after getting them home.

[Image: https://farm5.staticflickr.com/4212/3581...0ecc_b.jpg]

Here's a studio glamour shot:

[Image: https://farm5.staticflickr.com/4033/3487...35b0_b.jpg]

It needs a couple of little pieces of wood replaced up near the top of the speaker grill. That should be relatively easy to patch.

Here's the 2nd copy, I acquired through a barter deal earlier this year.

[Image: https://farm5.staticflickr.com/4011/3551...fa82_b.jpg]

[morzh]

IS yours the initial release or the code 123?

In the first case in the Rider's the values are missing, so the top cap has to be at least 450V (I use 600V - rated there), the bottom, if the values are equal with the top one, can be 300V, if much smaller than 450V.
630V to me is preferred.

In the case of code 123 the sch has a mistake: the cap #47 is shown as 0.15uF whereas it should be 0.015uF (0.15uF will muffle the sound so much it won't be good at all); , and the voltage - 450V to 600V for both.

[PhilcoPhan1936]

I started by pulling the chassis and speaker out of the cabinet.

This service tag fell out.

[Image: https://farm5.staticflickr.com/4472/2425...7171_b.jpg]

I took the chassis and speaker outside to dust off, then printed up the paperwork for it. I had to fight with my old printer for about an hour to get 2 pages printed.  

I have started highlighting the coils, transformers and resistors that I checked and have so far checked out.  

[Image: https://farm5.staticflickr.com/4462/3807...4e95_b.jpg]

[PhilcoPhan1936]

IS yours the initial release or the code 123?

In the first case in the Rider's the values are missing, so the top cap has to be at least 450V (I use 600V - rated there), the bottom, if the values are equal with the top one, can be 300V, if much smaller than 450V.
630V to me is preferred.

In the case of code 123 the sch has  a mistake: the cap #47 is shown as 0.15uF whereas it should be 0.015uF (0.15uF will muffle the sound so much it won't be good at all); , and the voltage - 450V to 600V for both.

I'll look and see if I can determine which it is, and report back. Under chassis pics coming soon.....

[Ron Ramirez]

Jeff

You want documentation for Model 89? Have you looked here?

http://philcoradio.com/phorum/showthread.php?tid=15002

Everything you would want to know about Model 89...all known (and some unknown) production changes, etc.

[morzh]

Yeah, the very first tone control simply would not work.....that is, as a control, as shorting out 0.15uF in series with 0.01uF will change the capacitance from 10nF to 9.4nF which would be barely noticeable and is less than the tolerance of the caps itself.

[PhilcoPhan1936]

You want documentation for Model 89? Have you looked here?

http://philcoradio.com/phorum/showthread.php?tid=15002

Thanks Ron! I'll look it over, and if I have any questions I still can't figure out, I'll ring.

[Ron Ramirez]

How is Felix-Antoine, anyway? Is he still in the Facebook radio groups?

[PhilcoPhan1936]

Felix is doing well. I think he has other interests and school that keep him busy. I still see him occasionally comment or post, but he's not as active in the groups as he used to be. I can pass your greetings on if you like.
Vincent also is quite busy with college, but he drops in and posts once in a while.