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

38-116 Code 125 Tube Heater Circuit Issue
#6

I re-checked voltages.  Still 723 vac between the plate sockets of the rectifier.  Voltage at cap 120 is still low.  279 vdc from + to chassis ground and 331 vdc from + to - terminal on original cap.  The voltage diagram says first should be 315 vdc and second should be 385 vdc.  The voltage on cap 123A is now -54 vdc; but, the voltage on cap 123 is only 318 vdc (should be 370).  Voltages on caps 70, 70A, and 70B are just slightly low; 245 vdc vs 260; 76 vdc vs 90; and 218 vdc vs 225.  The plate on the 6J5 driver tube still reads low at 54 vdc.

I checked resistance between rectifier sockets 7 and 8.  Supposed to be less than .1 ohm but I get much higher readings, from 3 to 10 ohms, depending on how the probes are positioned.  Also checked the vac between those sockets and got 5 vac.

By the way, I have the input voltage to the radio set at 115 vac.

Added edit: I very much appreciate the time you've spent educating and helping me with this radio.  I thinking about just setting it aside for now.  There is a much nicer 38-116 that will be sold at an auction near me this coming Saturday.  The cabinet is in much better condition than mine and the chassis has all its tube shields which means it hasn't been hacked to accept metal tubes.  


Messages In This Thread
RE: 38-116 Code 125 Tube Heater Circuit Issue - by LarryFS - 09-21-2019, 01:43 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
My collection presentation
This article has been completely updated and finished. The beginning of a portable collection.Vlad95 — 11:49 PM
Philco 50-295 antenna connections
Thanks Rod, That makes perfect sense. Is there a way to edit my post? It's a Philco 50-925 and not a Philco 50-295. D...keith49vj3 — 09:55 PM
Philco 50-295 antenna connections
C is for an external speaker.RodB — 08:39 PM
Philco 370LZ chair side not a 71LZ
Can you send a couple of pictures?slford310 — 07:11 PM
Philco 370LZ chair side not a 71LZ
Thank you for the reply. After much studying I figured it just sat there and you have to open the top and pull up and/o...Villager61 — 06:42 PM
Philco 370LZ chair side not a 71LZ
Sorry, I haven't gotten to this project yet, so I don't have the answer, but I bet one of the experts on this site does....slford310 — 05:54 PM
Value of capacitor
That’s what I thought, but when I’m undoing 50 years of “repairs” it never hurts to check. Thanksbridkarl — 04:03 PM
Value of capacitor
According to AI, "Yes, you're reading that correctly. A .005 capacitor typically refers to 0.005 microfarads (µF), ...HowardWoodard — 03:57 PM
Value of capacitor
I’m having to replace this audio coupling cap between the plate of a 6F6 and a phone jack. The parts list just says .005...bridkarl — 03:45 PM
Philco 50-295 antenna connections
Shoot, just realized that the blue wire connecting to the top of the tuning cap can't go to terminal D since that's on t...keith49vj3 — 01:20 PM

[-]
Who's Online
There are currently no members online.

>