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: 206

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
Model 70 Cabinet Trim
Although I have not made any cabinets or cabinet parts for a couple of years, I still have some parts left over, includi...Steve Davis — 06:26 PM
philcorepairbench.com - shadow-meter
Thanks Ron.fenbach — 02:43 PM
Model 70 Cabinet Trim
Thank you, Gary. Before making my original post, I had clicked on "Steve Davis Cabinets" only to find that it...musar — 02:25 PM
philco predicta
Welcome to the Phorum, cgl18! I am not your resource for television repair, but lots of friendly help is available here...GarySP — 02:12 PM
Model 70 Cabinet Trim
Welcome to the Phorum, musar! You can send Steve Davis a private message (PM). The site is at the top of the Home page...GarySP — 02:09 PM
Model 70 Cabinet Trim
How do I contact him? The only contact information for him I could find when searching online was a telephone number th...musar — 10:38 AM
philco predicta
Hello, good afternoon, I would like to ask what the possible problem could be if I don't have an image on the screen. I ...cgl18 — 10:19 AM
Philco model 38 code 121 not receiving signal.
So one last question before I finish this radio. Regarding the speaker and output transformer. I salvaged the original o...Stormlord5500 — 09:31 AM
462ron
It’s on the bottom of the homepage of our Philcoradio.com homepage! Ron462ron — 07:20 AM
Model 70 Cabinet Trim
Steve might have some trim left. Not sure he is making anything.morzh — 06:12 AM

[-]
Who's Online
There are currently 546 online users. [Complete List]
» 3 Member(s) | 543 Guest(s)
AvatarAvatarAvatar

>