The PHILCO Phorum
84b Power Transformer - Printable Version

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84b Power Transformer - percyjd - 09-17-2022

Recently acquired a Philco 84b radio.  Have to rewire, recap, and replace the resistors, so I pulled the transformer too.  When I tested to see if any of the windings were open and came up with the below values.  My question is in regards to the low reading for the windings supplying the filaments.  Based on a handful of restoration videos for this model, the reading is usually around 1 ohm. My readings are obviously much lower.  This is my second restoration, having previously refurbished a curb-find Philco 41-608 that really only need to be recapped and rewired. So I'm still just a novice.  Any help would be appreciated.

Primary (terminals 1 & 2): 10.2 ohms
Secondary to filaments on output tube type 42 (terminals 3 & 4): .4 ohms
Secondary to rectifier tube type 80 filament (terminals 6 & 7): .4 ohms
Secondary to the plates on the rectifier tube type 80 (terminals 9 & 10): 413 ohms
CT (terminal 8) to terminal 9: 215 ohms
CT (terminal 8) to terminal 10: 199 ohms

RE: 84b Power Transformer - Radioroslyn - 09-17-2022

Wouldn't be too concerns about the heater windings. If you are going to have bad ones the HV is the 1st suspect and the primary is the 2nd. In Philco set the pt are pretty stout. when you take the chassis out of the cabinet and there's a big gob of wax stuck to the cabinet that's the time to be worry about bad a pt. Most of the 84's have some other tricks up their power cords which we here on the Phorum can guide you thru if you like.

RE: 84b Power Transformer - percyjd - 09-17-2022

Thanks for your prompt response.  I wasn't sure about the lower values, so I figured I'd ask just to make sure I don't create more work later once I power the radio up for the first time.  Thanks again.

RE: 84b Power Transformer - Simon Wa3uay - 09-17-2022

I don't recommend this because you can be electrocuted. But, you can always apply power to the PT and see what you got!
-Simon

RE: 84b Power Transformer - Radioroslyn - 09-17-2022

OBTW here's the service bulletin for your 84. https://philcoradio.com/library/download/service%20info/service%20bulletins/Philco%20Service%20Bulletin%20178.pdf
 It's the entree level set ($20) to up sell a perspective buyer a more expensive set probably a 60 or 89. Philco sold a lot of 84's. Nowdays from what I've seen 84s vs 60's it's neck and neck. There's lot of both.

RE: 84b Power Transformer - percyjd - 09-17-2022

Thanks.  I've located three service bulletins regarding the 84B. The Philco Library has been a valuable resource as well as all the posts on this site.

RE: 84b Power Transformer - Radioroslyn - 09-17-2022

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