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Hello all
I am doing a 49-504 and in section 4 I see C401is that a 5mmf ? I did not see that when I replaced the caps.
Thank you
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Also wheni first power on the 7a8 gets very bright more than normal not sure what I did wrong
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https://philcoradio.com/library/download...8-1949.pdf
I wouldn't loose any sleep over the 7A8 filament unless you can use it for a nightlite. It's just the cold resistance of the filament is lower than the rest so it dissipates more power in brightness than the others. When it heats up the resistance rises and filament dims. Such is the life of a fil in a series strung set.
On the 5mmf cap if it's a mica leave it paper replace.
I had one of those sets many yrs ago. Nice clean cabinet design and a good player too.
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
(This post was last modified: 09-28-2024, 07:48 AM by
Radioroslyn.)
Posts: 88
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City: West Milford NJ
Posts: 88
Threads: 20
Joined: Apr 2012
City: West Milford NJ
So now I have an issue where as the radio gets warmer the volume gets very low and the stations don’t come in as well. Can this be a tube ?
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Hi philco4me,
So, your issue with the low volume after warmup could be a few things. One being what you suggested, weak tube. You can do 2 things to try and narrow it down. You can substitute the tubes one at a time, and I would start with the 14B6 detector. Or create a voltage chart of tube voltages right after power-on when the tubes are cool, should take just a few minutes. Then, when the volume decreases, read the voltages a second time. Keep in mind, if it's not a flaky tube, it could be a e sistor or capacitor changing value after having voltage applied. In either case you should see a change in voltage readings.
The other issue with the 5pf cap is more than likely a gimmick cap. That's two wires twisted together with one wire soldered to the tuning condenser, and the other wire connected to the loop antenna. You may have inadvertently removed them during your restoration. (What's up with these extra wires?) Hope this helps.
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Thank you for the help. All tubes tested strong so I will double check my recap.
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Would a bad r204 be the issue ?
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Possible yes likely not so much.
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
Posts: 88
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Joined: Apr 2012
City: West Milford NJ
I will test that one and see. Is there anything else you can suggest ?
Thank you
Posts: 88
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City: West Milford NJ
After some adjusting I was able to get a stronger signal but when the set gets hot and you turn up the volume it gets distorted yet when it’s first turned on it works fine. Any suggestions ?
All help is appreciated.
Thank you
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Check the cathode resistor for the output tube. If that does not resolve, get a can of freeze spray. If you can't get freeze spray, turning an air duster can upside down will give you freeze spray. With the distortion present, spray each component one at a time. DO NOT spray the tubes, they will crack.
Hope this helps.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis
Best Regards,
MrFixr55
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Hi, I would monitor the voltage on the control grid of the 50A6 pin 6. On 2 occasions on different sets I would see the control grid slowly go more positive after awhile and the sound would get weak and slightly distorted even though I had recapped it. Turned out the tube had gas or some issue even though it tested good. Make sure you replaced the C200 coupling cap on your set.
Ron
Bendix 0626. RCA 8BX5. RCA T64
Philco 41-250. Philco49-500
GE 201. Philco 39-25
Motorola 61X13. Philco 46-42 Crosley 52TQ
Philco 37-116. Philco 70
AK 35 Philco 46-350
Philco 620B. Zenith Transoceanic B-600
Philco 60B. Majestic 50
Philco 52-944. AK 84
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Thank you all. I will try both your suggestions and let you know.
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Replaced the 50a5 and the radio plays fine. The tube was the issue. Thank you all very much for your help