Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

84b Power Transformer
#1

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
#2

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.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#3

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.
#4

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
#5

OBTW here's the service bulletin for your 84. https://philcoradio.com/library/download...%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.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#6

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.
#7

[Image: https://philcoradio.com/phorum/images/sm...humbup.gif]

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Need Help to ID this radio 11 tube Philco
It is a 16B tombstone.morzh — 06:13 PM
Zenith H725
David - sorry, I reread your post and finally saw THD - now the % figures make sense. Thanks for explaining. The PSU...EdHolland — 06:06 PM
Need Help to ID this radio 11 tube Philco
Hi Everyone, New member but have been reading this for awhile for tips! Vaccum tubes were before my time so bear with ...Ken D. — 06:03 PM
My Philco 37-116 Restore
Thank you MrFixR55, I appreciate your comments very much. I do not detect much hum if any so I will be staying with the ...dconant — 05:15 PM
My Philco 37-116 Restore
Hi DConant Yes, you can replace chokes with resistors.  You do stand the risk of increased hum.  the solution is to inc...MrFixr55 — 04:23 PM
Zenith H725
1.7-3.9 %, a modified Sine wave inverter is around 25%. Most generators from big box stores run 10% at a 50% load. What ...David — 04:06 PM
My Philco 37-116 Restore
I am having a heck of a time doing the alignment on the AM band. I can't seem to dial in the 1500 KC oscillator. I can h...dconant — 03:35 PM
Zenith H725
David - I think I understand but what units are you discussing (Low of 1.7, high of 3.9)? Budget constraints for Ham ...EdHolland — 01:43 PM
My Philco 37-116 Restore
You're doing great. I wish I could be more involved, but my mind is right now preoccupied with the reason I am here in ...morzh — 12:21 PM
My Philco 37-116 Restore
Hope you guys are still with me. I have moved on to the alignment. I completed the IF alignment which was pretty muc...dconant — 10:47 AM

[-]
Who's Online
There are currently 750 online users. [Complete List]
» 1 Member(s) | 749 Guest(s)
Avatar

>