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

35WG-1570B
#1

Hi Guys,


I have an interesting problem this time. I Did a full recap on this AM/FM radio, along with a complete tube and resistor check. I got it all together and had it up in the kitchen where I've been listening to it for a couple weeks. I was listening to it the other day when all of a sudden the volume dropped and I had no sound on either band. Well, back to the bench. I plugged my iphone and was able to hear it just fine. Put the band switch back to AM or FM and nothing.
The weird thing is that one resistor-R16 a 1K, was starting to smoke. I swapped out the 6X5 but it didn't help. I retested all connections and they all look good. Any ideas? (35WG and 25WG)


Attached Files
.pdf usa_montgomery_airline_25wg_1570b_sch1.pdf Size: 337.58 KB  Downloads: 183

Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org

#2

Either the tube 68A6 or C19 cap, 5000mmf connected to that resistor, SG of the tube and output xfmr

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#3

(12-09-2016, 05:22 PM)Eric Adams Wrote:  Hi Guys,


I have an interesting problem this time. I Did a full recap on this AM/FM radio, along with a complete tube and resistor check. I got it all together and had it up in the kitchen where I've been listening to it for a couple weeks. I was listening to it the other day when all of a sudden the volume dropped and I had no sound on either band. Well, back to the bench. I plugged my iphone and was able to hear it just fine. Put the band switch back to AM or FM and nothing.
The weird thing is that one resistor-R16 a 1K, was starting to smoke. I swapped out the 6X5 but it didn't help. I retested all connections and they all look good. Any ideas? (35WG and 25WG)

Check for shorts to the chassis around L-13 and bad C-19.

GL

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
#4

OK, here's what I did. I tested the cap, IF trans and resistor. They all tested good, each one was removed from the circuit for testing. So I put it all together and with all tubes out except the 6X5 (the way I ran all tests). I ran up the voltage slowly, watching the resistor in question for any smoke. Got it up to about 110v with no smoke or heat. After about a minute of this there was a spark under the area of the tuning cap. No smoke or flame (Wow, I sound like kirk). I figured I can't hurt it anymore so I killed the power and installed the tubes. I ran the power up and after a few minutes the radio was working fine. No, I haven't checked where the spark came from, but I will. Thanks to everyone for your help.

Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org





Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
An attempt to remove the Field Coil from a G speaker
Gary I in fact did, on a 38-14, I think, where I had a speaker with the dead coil. Well...it kinda worked. Kinda, be...morzh — 10:38 PM
An attempt to remove the Field Coil from a G speaker
Mike, what ever happened to that plan you had to try using a rare earth magnet to magnetize the pole? This looks like a...GarySP — 10:25 PM
RCA T62 is playing.....
Beautiful set.morzh — 09:07 PM
An attempt to remove the Field Coil from a G speaker
Well....here it is. The green stuff. Unfortunately, probably penetrates deep. I opened the top layer and saw that: ...morzh — 08:58 PM
Philco 91 Restore Code ??
:clap: :clap: :clap: :clap: Really nice workmanship!!! Top of the chassis looks great. Sorry about the long winded e...MrFixr55 — 08:09 PM
Philco 40-120C Restoration
Thank you for your reply. I will check voltages on the other tubes, look at resistor 23 and cap 25, etc. If all else fai...bluecap — 07:58 PM
RCA T62 is playing.....
Nice looking set great save. DavidDavid — 07:48 PM
Philco 89 indicator light.
Hello Jim, I have done several 89s. The trick is to move the drum in or out on it's shaft. You will need to loosen a set...dconant — 07:36 PM
An attempt to remove the Field Coil from a G speaker
MrFixr Yes, it is my plan to go with 45rpm spider if I go that far. No, the pole was not left-handed as I unscrewed ...morzh — 07:14 PM
Philco 40-120C Restoration
Change the tube. Check the tube's bias network. Are any other tubes experience the drop or just this?` Is resistor 23 OK...morzh — 07:09 PM

[-]
Who's Online
There are currently 6705 online users. [Complete List]
» 1 Member(s) | 6704 Guest(s)
Avatar

>