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Philco 60 Antenna Coil
#31

Sorry no #5 ant trimmer.
#12 is for the osc.

Terry
#32

Help! Forgive my ignorance.

I'm noticing several different views of the alignment docs. Hope I'm using the right one. I'm trying to correlate these to my schematic.

I think #5 and #12 are the same. I've been using the one on the bottom.

See pic.


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#33

You need to know which version of 60 you have. They changed considerably with time. See
http://www.philcoradio.com/tech/60evol.htm
#34

I'm a 1934, Run#7.

Thanks, I was using an alignment instruction from a different thread, so I'm back to checking my measurements.

-Brett
#35

So, as an amateur, I don't only just want to fix this particular radio, I seek to understand.....

My question is this: If I send a signal into the antenna, and it makes it's way, (via audio), all the way through the various stages, to the speaker, and the radio is aligned, yet there are no AM stations except a local boomer, where should I be focusing my attention?

-Brett
#36

(10-06-2015, 10:41 AM)Caperodder Wrote:  So, as an amateur, I don't only just want to fix this particular radio, I seek to understand.....

My question is this: If I send a signal into the antenna, and it makes it's way, (via audio), all the way through the various stages, to the speaker, and the radio is aligned, yet there are no AM stations except a local boomer, where should I be focusing my attention?

-Brett

Your antenna.

Crist
#37

I'm grounded, and have 20' of wire.

-Brett
#38

Have you tried connecting the antenna directly to the grid cap of the 6A7?

Steve

M R Radios   C M Tubes
#39

Steve DavisHave you tried connecting the antenna directly to the grid cap of the 6A7?

Steve

I'll try that next. Also suggested by Terry through a 30 pf cap.

-Brett
#40

(10-06-2015, 02:00 PM)Caperodder Wrote:  I'm grounded, and have 20' of wire.

-Brett

Is the wire outside?

Turn off flourescent lights.

Try another location, like a buddies house.

Crist
#41

As soon as I am home from travel, I'll be all over it! We're gonna beat this thing.

Thanks for the ideas.

-Brett
#42

Hi Brett,
Something else that can mask good reception is computer switching power supplies, phone chargers,and lap top chargers. Those things can generate alot of RF noise. It can be radiated though the house wiring and cover up the BCB and up into the SW bands easily. I end up unplugging my chargers and such if I going to listen that isn't a local blowtorch.

Terry
#43

OK. Tried lot's off different things.

20' of antenna wire.
Radio grounded.
No fluorescent lights.
No battery chargers.

To be even more certain, I took the radio outdoors.

Only the faintest reception of a local boomer. Connected antenna directly to the grid cap of the 6A7, and also through a 30pf cap. No significant difference.

This is exactly why I put the radio aside last time. I'm not giving up till it's fixed! Going to go through the wiring again lead by lead, and recheck values.

-Brett
#44

Ok....checking and rechecking.

I pulled the antenna coil from the chassis, and here is what I have:

From the bottom view:

Lugs -
(1 & 5) .7 ohm (This is the one I had originally rewound. 6 turns clockwise, starting toward the bottom. See pic)
(6 & 4) 6 ohm (schemo says 1 ohm)
(4 & 3) 5.5 ohm (perfect)
(3 & 2) 6.3 ohm (schemo says 1 ohm)
(5 to top of coil) 11.4 ohm (perfect)

Two questions:

1. Should I be concerned about the two 6 ohm readings?
2. Did I turn the new windings from lug 1 and 5 in the right direction?

I've checked other posts. Just looking for a sanity check.

-Brett


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#45

Brett,

I just finished a Philco 60 restore. I had to rewind that outer winding 1 & 5 like you did. Mine is exactly like yours. About 7 turns clockwise from the bottom. Based on the 11.4 ohms from the top of the coil, I think your primary (left side) sounds good.

I also had to rewind the windings between 4 & 3 and 3 & 2. The 3 &2 winding connects into the 4 & 3 winding right at a spot underneath the plastic insulator under all that crud. The wires drop down through the hole and meet at one of the pins I believe. Mine was completely open. I had no continuity on the 3 & 2 winding. I don't know if that is your problem or not. But it would require that you remove the 1 & 5 winding and cleaning it up, removing the plastic insulator, the crud, etc.

The 3 & 2 winding is much thicker wire. I used 32 ga., but I bet it is even something more like 30. My notes say 25 turns CW looking from the bottom starting at pin 2. But if you do it, you should use this information to double check what you see on yours. I don't want to be responsible for giving you incorrect info.

Like others have said above, you should be able to get some reception with just some wire attached to the grid of the 6A7. If you don't, the antenna coil may not be your biggest problem.

Also, I tend to disagree that you need 20 ft of antenna wire and a ground. I work in my basement, and usually with 3-4 ft. of antenna wire, I get pretty decent reception. I have never tried a ground.

Mark K8KZ

EDIT: The resistance between 6 & 4 also sounds strange. My measurement was pretty close to right on. I didn't rewind that. It is the winding at the very top of the coil form. Maybe a couple dozens turns of the thick wire. Maybe a visual inspection would be a place to start with that.

Another thought... If you have a signal generator, apply a 1200 Khz modulated signal (as low level as possible with the volume turned up to max) to the cap of the 6A7. Tune it in and and try peaking the IF condensers. Basically align the IF. Certainly if the IF passband is off, you may not get much reception and that is all downstream from your antenna coil. I don't know if you have done that or not.




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