Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

philco 89 model 123 with short wave open interstage transformer
#1

Hi all 
need nelp I have a philco 89 model 123 with the short wave
I have a open interstage transformer (2) coil between rf and oscillator coil and can not seem to locate the spec of the primary side of coil ,
mine is very corroded in one spot and open with almost every turn
does anyone have specs on this coil ie number of turns and wire size ?
kinda new to this hobby I have some magnet wire but prob not correct guage
... please any help you welcome to email me not sure if this is allowed Westerngardener@msn.com or KB7KP@usa.com

thanks Art-
#2

Never worked on a 89 but have some info that might help. Beitmans list ohms for the coils so can guess at length of wire. Link to the Philco library.  https://philcoradio.com/library/  Plus a sch from Beitmans.       
#3

All the information needed is in the coil itself. Map the coil to a sheet of paper to locate the lugs, connections and winding data. Remove start or finish end of the top most winding, carefully. The coil will be sealed with a combination of bees wax and a hard damar wax. A solvent like odorless mineral spirits and a heat gun can be used to carefully clean the coils in place. Be careful be sure all mineral spirit is off  the coil and out of the work area when firing the heat gun. With one coil end removed use either calipers or a micrometer to get the diameter, subtract 1 or 2 thou. for the film coating. Use a magnifier and a wooden probe and count the turns and direction. Make the notes on the coil to the paper. When all data is on the paper in the form of a diagram with text, soak the form with mineral spirits and slowly unwind. keep all the wire bits for possible data recovery, (length). The winding liner is likely celluloid, it rots and the acids take the winding out. Kapton tape can be used as a liner or acetate sheet. When all turns are off and counted clean the coil form completely, use a lighter solvent if need be.

Prepare 1-1/2 cups of meted bees wax at about 150F, double boiler or electric hot plate do not over heat. Place the cleaned form in the wax and soak for 5 minutes, it may bubble, let that happen as it is moisture. Remove the form while hot, there will be a thin film of wax... Do not wipe off, the film is tacky and will grip the turns of wire so they won't unravel. With the data sheet and the tacky form, wind the coil. The project can be stopped for a break because the wax will hold the wire. Wind the first layer, place the liner (tape). Brush on with acid brush more wax, heat of wax may cause the tape to fail so do not dunk. Complete the winding. Solder the leads in place. Dunk the entire coil into the wax quickly, remove let cool then repeat twice more, allowing the form to cool in between dunking. A thick film of wax will seal out all moisture. The coil is complete and can be installed.

Use real refined bees wax not paraffin or bees wax blend for candles. These melt at too low a temp. and are slippery, not tacky. The lighter the color of the bees wax the more refined it is...

GL

Chas

Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
#4

Hello Chas,
Thanks for the Tip I use Use real refined bees wax for my Capacitor's .
Sincerely Richard
#5

If you are talking about the primary of the ant coil #2 I would go w/20' of 38G wire.

https://philcoradio.com/library/download...20146B.pdf

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




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Jackson 715 not working
Now that you posted the schematic, I don't know why that Sprague electrolytic cap is across the meter, as it is not indi...MrFixr55 — 05:51 PM
HiFi (Chifi) tube amp build - but my own design.
What may be lacking in the PP Tube amps may be the 2nd harmonics, which some, especially RCA back in the day called &quo...MrFixr55 — 05:32 PM
Jackson 715 not working
Usually in an emission tester, the tube under test is measured as if it were a diode. So, some testers connect all the g...RodB — 04:17 PM
Restoring Philco 37-604C
Yep. F5 is green, D5 is Red. Red is Bad. Green is Clean.morzh — 01:30 PM
Jackson 715 not working
I did start to do that but I stalled out because I could not figure out how the grid and plate get voltage. In this diag...daveone23 — 11:52 AM
Restoring Philco 37-604C
(Insert Homer Simpson "DOPF" Here.) When all fails, look at the can. Took the Ron Ramirez advice, red Caig D...MrFixr55 — 09:23 AM
Philco 91 Speaker Replacement
From your text I am not sure if you intend to use the existing speaker with a resistor instead of the field coil. It wo...morzh — 08:44 AM
Philco 91 Speaker Replacement
My field coil is bad. I am still hoping to find an original, but if I can't I will go with a fitting Philco speaker, 125...dconant — 08:34 AM
Philco 91 Speaker Replacement
As Rod said, it is OK to use a fitting speaker, and then look for an original one. If you buy a Hammond 125 output tr...morzh — 08:15 AM
Philco 91 Speaker Replacement
Yes, I often have to substitute, then keep an eye out for an original. In the meantime, the radio is working and being e...RodB — 08:02 AM

[-]
Who's Online
There are currently no members online.

>