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Ok guy's, here is where we sit with my Philco 300x console.
Seems that I might have a couple bad coils.
Will take it to my buddies for re-check.
Don't trust my readings.
I think the antenna coil for the broadcast band is open, and probably the broadcast band oscillator coil.
Can these be re-wound by someone on the forum?
I won't know for sure till next week.
This radio has been a pain in my rear end for sure.
Maybe $30 wasn't such a great deal.
Has shut my radio re-furb hobby down till I get this one figured out.
Then it's on to another problematic 40-180 chassis.
But, it is still fun doing this with the limited knowledge that I have.
Everyone have a great weekend!
murf
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Murf
I was myself afraid of oils but found out that solenoid type (one layer lengthwise) are in fact very simple and easy to rewind.
It is likely those coils are this type. If yes, give it a try, it is a 20 minute job.
Those that wound radially, mening many turns over short length, multilayer, those are worse, and will require some fixture, or at least some cardboard bobbin ends, and myself I did not do that fancy criss-cross pattern, but it worked too.
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Murf;
It is not normal for more then one coil to be bad at one time. Normally if one is bad it's because lighting hit an outdoor antenna and destroyed the antenna coil, however in the 41-300's case this is less possible then usual as the set uses a built in antenna for the AM broadcast band. In the case of the BC oscillator coil it isn't a known failure point on Philcos of this era, but strange things do happen. I think maybe it would be wise to get a second opinion from your friend, while the schematic shows what points to measure on each coil, and has a pictorial diagram of each coil, if you aren't used to testing such things it can be confusing.
Regards
Arran
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Arran
I have to disagree. When I was repairing my 70 I had two coils open.
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Hey Murf:
I have to agree with Aaron on this, the early Philcos had the coil issue but the later ones did not and the chances of two being open is slim. Get your friend to check it out.
Gregb
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The only thing I have to agree with, I found old soldering on coils oxidized (or whatever that dull film on top is) the meter probes do not make contact unless those are sharp neede types.
So when first I get open reading (same happens when I check resistrs) I persist, trying to scratch the film. About 60% of them are like that in my experience. And coils exacerbate the situation as the contacts are flimsy and poorly attached to cardboard, so I am reluctant to really push my probes into it being afraid to break the wire or the contact. So make sure you have the contact when buzzing coils.
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I often reheat the solder on coil terminals and use some rosin core flux or add a small amount of new solder along with some rosin flux to renew the connection. If there was a poor solder connection in the beginning it will often establish a new good connection. the soldering operation does not create the stress that pushing on an old coil terminal with an ohm meter probe/s would. Some good needle-point ohm meter probes do help in dealing with old oxidized solder.
Joe
KC5LY
(This post was last modified: 07-20-2014, 01:32 PM by Joeztech.)
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Good point Joe, I find that reflowing some solder fixes 50% of bad coil issues. I also find that if that doesn't work have a good close look under a magnifying glass and you will find a break in the wire right there at the connection point.
Gregb
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Hi guy's,
I tried getting consistant readings on both coils, and found that it was tough to get the same reading twice.
Maybe I will try re-working the solder connections as stated.
I will get a second opinion though for sure.
Thanks for everyones advice.
murf
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I have to agree with Mike (Morzh) on this one. I've had Philco 89 sets cross my bench in which all three coils (antenna, RF, oscillator) were bad.
--
Ron Ramirez
Ferdinand IN
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Well, checked by someone more knowlegable than me, and bothe broadcast antenna and oscillator coils are open.
Luckily, John on the phorum has a parts chassis and offered both coils.
What a lifesaver.
Can't wait to install them and get it playing again.
Thanks to everyone for the help.
murf
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Murf;
Once you get the replacement coils, save the old ones. You might later want to try rewinding them. I think you could do a good job on that since you have examples of good ones.
Joe
KC5LY
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Good news,
Coils came today and I installed them before dinner.
Powered it up, and it works like new.
Thanks everyone for your help on getting this radio playing again.
THis has been my greatest challenge as far as radio's go.
Special thanks to John, who so graciously supplied the 2 coils.
Hurray!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
murf 
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murf;
Great job! Glad to hear the repairs were successful. This hobby has lots of great people like John around to help along the way.
Joe
KC5LY
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