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Ok.. Its re-wound. Got correct plate voltage across all points now. Still only tunes in that one channel. Starts around 1200khz and gets really loud and clear at the extreme end of the tuning caps range 1500khz(where it stops turning). No other stations will come in. The volume control works now too. Im at a loss here. I'm used to seeing variable caps and adjustment slugs on the RF towers. Trimmers and such. Whats the next step?
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State, Province, Country: Indiana
Unless you have an early production model, there should be three trimmers mounted on the side of the tuning condenser.
Alignment is simple, but you should do this carefully:
Tune your signal generator to 1400 kc.
Tune the Philco to 140 on the dial. Turn the volume control wide open and use the weakest possible generator signal so that it is audible without being too loud.
Adjust the trimmer closest to the back first, then the one in the middle, then the one in front. Adjust each for maximum output.
You may not hear the signal when the Philco dial is at 140, so tune in the signal and carefully adjust the trimmers so the 1400 kc signal "moves" to 140 on the dial. This is done by readjusting the tuning condenser as you adjust the trimmers.
--
Ron Ramirez
Ferdinand IN
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Do the trimmers look like brass nuts screwed down over lugs protruding thru copper plates on the left side of the condenser? Sorry if thats a crude description...
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What should I attach to the ground clip on the chassis? Should it go to a water pipe or ground rod outside the house? How long should the antenna be? Loop it?
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The answer to the first question is yes.
Gnd connection can be a water pipe,gnd rod,or gnd pin on wall outlet.
Ant connection a wire that is as long and as high as you can make it. Clear of power lines and metal structures.
http://www.radiolaguy.com/images/misc/AM...ltions.jpg
Terry
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
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Some goofball before me turned all the trimmers tight. I'm still working on it.
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And unfortunately my sig generator only goes to 1000 khz. Dunno how to work with that. I will be so glad when I've learned more. I feel like an idiot with these sometimes.
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I'd loosen up about 4 turns from being tight. Find a station around 1400kc and align the set to that. You will find that tuning is a bit broad compared to a superhet and there isn't an adjustment like the oscillator which will cause the stations to move quickly across the dial. Then you are aligning a TRF set what you are doing is peaking each rf amplifier at a set frequency. There is no low frequency padder like you may have on a superhet.
Terry
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: 40
Threads: 2
Joined: Jul 2011
Had a ground issue but figured it out. With that and a good antenna it tunes pretty well across the dial. I aligned it to 1000kc because thats what my transmitter broadcasts at. I hooked up a modern speaker and it does sound surprisingly good. Plenty of volume and a nice warm tone with a hint of treble. Now I need to get it set up with a seperate output trans and choke (which i dont have) so I dont have to have the original speaker hanging around the cabinet. Maybe something in my misc parts box. Would any choke work? How do I wire it in? I'm learning slowly but surely... Thanks for all the help so far. I would be lost without you guys.
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So what was the problem with the original?
Terry
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: 40
Threads: 2
Joined: Jul 2011
The voice coil is locked up on the pole piece. No cone travel at all. Also the cone is torn and has seperated from the surround over almost 2/3rds of it's circumfrence. The cordset from the chassis is worn through in 3 places and the wiring from the output transformer to the wire lugs on the basket are crumbling to oblivion. Other than that its just fine.
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I would probably do the easiest thing. That would be find an 8" speaker and just wire the VC to the output transformer mount it in the cabinet. The cord can be repaired with some shrink tube once unsolder at the spkr end. As you may notice the spkr plug is not a standard 4 pin (tube) base as it only has one fat pin and 3 small ones. Your original speaker sounds repairable and is not very difficult to recone. A used one is going for $75-100.00. A replacement 8" cone can be had on epay for about $10. You'll want the one with a 1" center hole and 1 1/2" depth.
Terry
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: 40
Threads: 2
Joined: Jul 2011
Yeah, the original is pretty much a "basket" case..
![Icon_lol Icon_lol](https://philcoradio.com/phorum/images/smilies/icon_lol.gif)
I will definitely repair it though. I built a small 2-way speaker to use for now. I'm going to remove the output transformer and use a 10 watt resistor for the field coil so I dont have the stock speaker hanging off the back of the cabinet. It really does sound good though. Not exactly Hi Fi but definitely nice for an 80 year old radio. Anybody going to Kutztown in a few weeks?
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If you are going with the 10W resistor you may have a hum problem unless you increase the value of the filter caps (not the input cap). A choke will work much better. Value isn't very critical 5-10H @ 75-100ma would work ok. If you have an old power transformer or a big output transformer you can use that for a choke too.
Terry
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: 40
Threads: 2
Joined: Jul 2011
I have a pile of transformers. Which would you recommend? How would I wire it in? I have the choke from an old Admiral console (7c64). Would that work?