Posts: 1,107
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City: Tacoma
State, Province, Country: Washington
Good chance this beauty blared out ".. a date which shall live in infamy...", being one of the last sets put out before we entered the war.
This one drove me a bit crazy(er) for a while. Hooked it up to a D cell and 90V DC and all I got was a pop. Looked at the current draw and the DC supply meter was pegged, over 150mA.
Changed out all the paper caps (5) and the electrolytic. Nothing changed. I disconnected the B+ from the output tube, still no change. Disconnected the B+ line to the rest of the tubes, current dropped to zero. Reconnected the output tube, current now at 14mA (still seems a bit high to me, but much better).
I couldn't find any problems with the IF cans or any other shorts. I reconnected the B+ line to the IF/RF sections, back to over 150mA. I scratched my head for a bit then decided to pull the tubes one at a time to see what happened. Pulled the output first. No change on the meter. Pulled the 2nd Det/AF, still no change. Pulled the IF tube. Bingo! Current dropped to about 3mA.
When I looked at the tube, I noted that it was a 1A7: NOT the tube that belongs in that socket. Looked at the tube in the 1st Det. socket: Aha.. there's the IF tube! Switched these two around and turned the radio on YES! it works Total current draw: about 22mA.
Just got the information download from Steve. I see that the total current draw on the B+ is supposed to be only around 7mA.. so it's drawing 3x what it should. Wonder if this means I have a gassy output tube? The sound is a bit muddier than I think it should be....
Posts: 1,107
Threads: 88
Joined: Jun 2011
City: Tacoma
State, Province, Country: Washington
Ron,
Please move this thread to the Philco Home Radios section. Thanks.
Brenda Ann
Posts: 13,776
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Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Done.
--
Ron Ramirez
Ferdinand IN
Posts: 1,107
Threads: 88
Joined: Jun 2011
City: Tacoma
State, Province, Country: Washington
Well.. it's finished. Found all the problems. The biggest one was apparently my DC supply. Though the range switch was in the 150mA position, it was actually showing the 30mA range. Switch was dirty. Radio is actually drawing about 7.2mA. Also changed out the grid bias resistor, which had drifted from 2.2 to over 6Mohm. This seems to have cleared up a lot of the muddiness.
Had to restring the dial cord. A shame, too, since it had apparently been done in the not too distant past with modern dial cord. But the sheathing had come apart where it went around the tuning shaft, and would not go past a certain point.
Everything works like a champ now. Always amazed at how well these little farm sets pull in the stations. In fact, if I hook it to my random wire (approx. 100'), it's too much for it. I think I can probably blame that on my friendly neighborhood 1.5MW flamethrower across the bay.
Posts: 54
Threads: 8
Joined: Nov 2012
City: Wilton, Iowa
Did you make up a supply for this unit, or is it a commercial one? I re-capped
a 41-95 a short time ago, & it really brought in the stations with just a 10 foot
antenna in the house.
Congrats on your success.
Jim
Posts: 143
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Joined: Dec 2013
City: Ithaca NY
Brenda,
I am curious as to your living situation. You mentioned a 100' random wire antenna. When I think of Korea I think of high rise apartment buildings and not a lot else in residential areas. Where do you manage to string up a 100' wire?
Congratulations on the newest restoration. I have never dealt with farm radios. It is something I will have to keep an eye out for in the future.
Regards,
Herb S.
Ithaca NY
Posts: 1,107
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City: Tacoma
State, Province, Country: Washington
Herb,
I'm lucky enough to live in a small enclave of smaller residences. We control two adjacent buildings, one of which has my shop, a sublet, and guest accommodations. The random wire runs up the side of that building, then goes in a 3/4 loop around the building roof. I'm actually giving some consideration to closing the loop (running that last wall, and then down and connect the other end to the ground) to see if that lowers my hideous noise level.
Farm radios seem to run the gamut from some really poor performers to ones like this one that seem to hear almost everything. I have one farm set, a GE U-80, IIRC, that is quite the set. 3 bands, 8 tubes, vibrator supply (6V). Good performance, nice sound (P-P output).
Posts: 143
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Joined: Dec 2013
City: Ithaca NY
OK, it sounds interesting where you live. We have friends here in Ithaca from Korea and they always say how there is so much more living space here in the US compared to Korea.
I have just never run across farm sets myself although I've certainly heard of them.
Posts: 1,107
Threads: 88
Joined: Jun 2011
City: Tacoma
State, Province, Country: Washington
In most of Korea, it is indeed very VERY densely populated. There are over 54 million people here in a place roughly the size and shape of the state of Indiana. Even the town we live in is that way along the outskirts, but the town center is more of a densely packed small town, as contrasted with the high rise buildings outside of town. Most of the buildings are four floors or less, ours are 2 1/2 floors, with part of the basement floor being above ground.
Below is a shot I took from the roof of our building. The structure on the left is my former shop, now our SMATV headend. You can get an idea of the density of the neighborhood. As I said, we're fortunate to be in a small enclave with access to adjacent buildings, which gives us room to stretch our legs, as it were.
Posts: 143
Threads: 11
Joined: Dec 2013
City: Ithaca NY
OK, thanks for the photo. Very interesting situation!
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