Philco 38-15 2nd IF transformer

View previous topic View next topic Go down

Philco 38-15 2nd IF transformer

Post by Ben Delk on Thu Jul 26, 2012 9:04 am

Have a Philco 38-15 with a bad 2nd IF transformer (mounts under chassis not in a can). After some early morning (3 a.m.) research it looks like the following models use the same transformer.
38-12
38-14
39-6
39-7
39-8
Any reason using this as a replacement will not work?

Ben Delk
Member
Member

Number of posts: 426
Age: 64
Registration date: 2012-04-03

Back to top Go down

Re: Philco 38-15 2nd IF transformer

Post by mr_ed01 on Thu Jul 26, 2012 5:43 pm

All models you have listed use part # 32-2674 as the 2nd IF transformer.

mr_ed01
Member
Member

Number of posts: 60
Registration date: 2012-03-16

Back to top Go down

Re: Philco 38-15 2nd IF transformer

Post by Ben Delk on Thu Jul 26, 2012 6:43 pm

Thanks for the reply. Yeah I check each model schematic and parts list and they all have the part number.
So they should be set to the same frqz and work ok?

Ben Delk
Member
Member

Number of posts: 426
Age: 64
Registration date: 2012-04-03

Back to top Go down

Re: Philco 38-15 2nd IF transformer

Post by sprman on Thu Jul 26, 2012 7:31 pm

They should work but you may have to tweek them a bit once installed.Sprman

sprman
Member
Member

Number of posts: 376
Age: 59
Registration date: 2008-03-27

Back to top Go down

Re: Philco 38-15 2nd IF transformer

Post by Ben Delk on Thu Jul 26, 2012 7:50 pm

Sprman good, sprman wise.......thanks sprman

Ben Delk
Member
Member

Number of posts: 426
Age: 64
Registration date: 2012-04-03

Back to top Go down

Re: Philco 38-15 2nd IF transformer

Post by Ben Delk on Tue Jul 31, 2012 11:43 am

Parton me guys...some days I feel more of an idiot that I'd like the rest of the world to know.

Purchased Philco 38-12 that I'm robbing the 2nd IF out of to put in my 38-15. Part number be the same on the IF it should be really close on the setting already. I've been fortunate enough
(that means lucky), not to have to adjust any IF cans on any of the radios I've rebulit so it is about time I learned the process. I seen and heard different ways to go about this. Some say if it is close just max in and out signal on the trimmers to the best receiption starting with the 2nd IF and work back to the 1st. Some say the opposite. Some only use a sig gen and vtvm and follow the schematic guide. Mind throwing your 2 cents worth in on it? I have a Heathkit IG 102 sig gen and RCA Senior WV-98c VoltOhmyst but I'm not sure how all this hooks up to check it.

http://www.nostalgiaair.org/Resources/239/M0013239.htm

http://www.nostalgiaair.org/Resources/274/M0013274.htm



Last edited by Ben Delk on Tue Jul 31, 2012 11:48 am; edited 1 time in total (Reason for editing : update)

Ben Delk
Member
Member

Number of posts: 426
Age: 64
Registration date: 2012-04-03

Back to top Go down

Re: Philco 38-15 2nd IF transformer

Post by jerryhawthorne on Mon Nov 05, 2012 5:57 pm

Ben, I would follow the directions given in the schematic, adjusting the directions for your particular signal generator. Sending a modulated fixed frequency signal from your generator will result in a tone on the output of your radio. Two key points here:
1. A fixed tone frequency is stable. Using a radio station to monitor output to your meter, or ear, might work for a rough alignment, but not a precise one. The signal level to your speaker or meter will jump all around.
2. Make certain your signal generator is at precisely the IF frequency you need. Mine certainly is a little off trying to read the dial. A frequency counter can allow you to get it dead on. I'm fortunate to have a scope with a frequency counter feature. Others here can probably suggest some small inexpensive counter to hook to your signal generator to make certain you are where you should be.

Follow the manufactures recommendations, keep your signal generator output as low as you can to still get a reading on your meter. Especially if your radio has AVC, which will try to keep reducing it if it gets too high. This is why some use the AVC line to measure output on a meter. Personally after peaking a trimmer or two if the tone is getting loud, I further reduce the signal level of the generator. Another reason I do this is the dang tone drives my wife crazy. Not too bad for me, I just turn off my hearing aids!

Hope this helps you a bit. I will assure you that every old radio that has been restored will benefit from the IF alignment. Well, to varying degrees.

Good luck and I'm certainly not the brightest bulb on the forum. I just work from some experience and trying to make things simple.

jerryhawthorne
Member
Member

Number of posts: 246
Registration date: 2012-10-12

Back to top Go down

Re: Philco 38-15 2nd IF transformer

Post by Ben Delk on Mon Nov 05, 2012 6:05 pm

I'm still trying to get back to this radio. Good info, thanks

Ben Delk
Member
Member

Number of posts: 426
Age: 64
Registration date: 2012-04-03

Back to top Go down

View previous topic View next topic Back to top


Permissions in this forum:
You cannot reply to topics in this forum