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Ready for 41-290 upgrade - Printable Version

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Ready for 41-290 upgrade - madghost - 11-23-2005

OK, I am ready to start on the electronic restoration of my 41-290. I pulled down the "Replacing Capaciators in Old Radios" article off the Philco web site. Here is what I came up with taking readings off the caps themselves:
Non Electrolytic paper caps:11
2X .o5 mfd/200 Volts
1x ? mfd/400 Volts (part # 30-4518s)
4x .01 mfd/400 V (part # 30-4572)
2x.003 mfd/?V (part 4469)
1x .002 mfd/?V
1x ? mfd/? V (part 4472)

Two Electrolytic Caps
1x 12 mfd/400v (axal lead)
1x ? mfd/400 v (dual lead on one end)
The schematic I pulled down off the web at Nostalgia Air is in a very small font and I have trouble reading it. Also, it doesn't have the same complete parts list like I have seen on the some of the Zenith Schematics that inlude mfd and Volt rating in the parts table.
So, can I use the standard orange drop capacitors to replace the paper non elctrolytic using .05 .01, .033 and .022 replacements? Can somebody help me with the unknown Voltages and Mfd rates shown above?
As to the electrolytics, have I identified them all? Of the two I have id'd, can I use a 22mfd/450 or 630Volt replacement for the 12 mfdx400 V? What about the second one? Both of these were found underneath the chasis held in place with a soft metal clip to the chasis. Also, I can't seem to find a dual lead Electrolytic cap in my RD catalogue. Any tips?
Any assistance would be greatly appreciated.

Thanks much, MG


- Ron Ramirez - 11-23-2005

Dude, before you go much further you really need to acquire a readable schematic. There are two Philco web sites; this is one of them, Chuck has the other. Do yourself a favor and order the service info from Chuck's site; you will be glad you did.
http://www.philcorepairbench.com/schematics.htm

Now on to your questions:
30-4518 - .05 mfd, 400v
You can use replacement metalized film capacitors (or Orange Drops if you prefer) rated at 600 or 630 volts for all but the electrolytics; that's what most guys do rather than mess with the 200 and 400 volt units.

The dual electrolytic is 8 and 16 uF (mfd), 400 volts. You probably won't find a new dual unit of this type, you'll have to use two separate electrolytics. Replace the 8 uF with a 10 uF, and the 16 uF with 22 uF. Use electrolytics rated at 450V.

Good luck,


READING SCHEMATICS - madghost - 11-24-2005

OK, I'll admit it, I am an electronic illterate (much like my computer skills). I took the latest advice and I made a blow up of the 41-290 schematic. However, I am having trouble deciphering the schematic. I can't seem to make the mental connection (pardon the pun) from the schematic diagram to what I see under the chassis. Does anyone have a diagram that is superimosed on a picture of the under chassis components? Any tips? Also the schematic of the 41-290 I have does not have a parts list nor a component diagram that shows me where the components are under the chassis. I have ordered the diagram from Chuck's site as suggested by the last poster, and hopefully that will help.
BTW, Happy Thanksgiving to All.


- Ron Ramirez - 11-24-2005

I can see where you would have trouble following the schematic if you enlarged the Nostalgia Air scan - it's fairly low resolution to start with, and when you enlarge it, detail gets fuzzy pretty quick.

The info you get from Chuck will include an under-chassis illustration, but it will not show the wiring underneath - only placement of the parts. Unfortunately, such an illustration (showing the wiring as well as parts placement) was never made, and is not available. RCA was good about doing this, but not Philco. (did I say that? Icon_eek )

I've sent you an e-mail on this subject.

Hang in there - you can conquer it. We're here to help.
--
The last poster Icon_smile


- Chuck Schwark - 11-24-2005

Yes, I got your order Keith - thanks. Like Ron says, the info packet you'll get has a fully annotated schematic (parts values and tube pin voltages) and an underside chassis parts placement diagram, Production change notes, as well as a dial cord stringing diagram, parts listing alignment instructions and pushbutton alignment info.

And Happy Turkey to you. Icon_smile


tv input - Guest - 12-14-2005

Chuck Schwark Wrote:Yes, I got your order Keith - thanks. Like Ron says, the info packet you'll get has a fully annotated schematic (parts values and tube pin voltages) and an underside chassis parts placement diagram, Production change notes, as well as a dial cord stringing diagram, parts listing alignment instructions and pushbutton alignment info.

And Happy Turkey to you. Icon_smile

I ordered the same information a few weeks and its great stuff. Per info "these models are designed to receive the sound of a tv program tuned in by special type Philco Television Radios.". Alright, is there anyway to input a lineout off of a cd player or some other device.