Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

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

Repair IF transformer in 39-6
#16

L= inductance C=capacitance and F= frequency. 470kc is the IF frequency for this set.

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
#17

Yes, there IS a meter for that. This one can be used to measure cpacitance, inductance, and resistance.
https://www.ebay.com/itm/LCD-1999-BM4070...SwvMVcdNWj
hope this helps.
#18

Also, as Mike (Morzh) said, to be successful in this hobby one really needs to acquire a good understanding of basic electronics. I strongly suggest the book Audel's Radioman's Guide. It can be had reasonably from Amazon. Any of the older (pre 1960) editions are good for what we need for this hobby.
https://www.amazon.com/Audels-New-Radiom...way&sr=8-5
#19

Mike the Druid

Thanks for that link to the LCR meter! I think I should pick one of those up. It might serve me well for those pesky Philco coils. Edit: Ordered. Icon_smile

--
Ron Ramirez
Ferdinand IN
#20

https://www.ebay.com/itm/Stanford-Resear...ctupt=true

I have this.
Got it for free.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#21

If you only broke off one of the leads to the coil, it is quite possible to very carefully, with a good magnifying device, find the broken end of the wire in the coil. I've done it before using a jeweler's loupe and a dental probe. Then you may be able to unwind just enough of the wire to reach a connection point or connect to a new lead. Twist the tiny wire around the connection point and heat with a very hot soldering iron, then apply solder. If the soldering iron is sufficiently hot, it will melt off the insulation; trying to scrape it off is very difficult. If you only unwind an inch or two, the change in inductance and resistance will not be problematic.
#22

I ordered one too!
#23

Thanks for this advice....  I bought new prescription eyeglasses after I made my boo-boo.  I'll get a magnifying glass also.
#24

Somehow, I did not realize there were hand-held meters out there that measure inductance..... That is VERY tempting, more-so for my loudspeaker work .   I  believe I'll get that.  Thanks Icon_biggrin
#25

Incidentally Stonewall ,
. . . . the insulation on that tiny wire is fiberous, . . . not rubber or any kind of plastic. It was this fiberous stuff that made me think I was just picking out a piece of lint or debris out of the chassis. I couldn't see it well-enough to realize it was a conductor with cloth insulation. Thanks again for your magnifying glass suggestion.

Jake
#26

Typically it would be silk or cotton.

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
#27

All natural Icon_smile

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#28

(03-15-2019, 12:04 PM)mikethedruid Wrote:  Yes, there IS a meter for that. This one can be used to measure cpacitance, inductance, and resistance.
https://www.ebay.com/itm/LCD-1999-BM4070...SwvMVcdNWj
hope this helps.

I got the meter.  Thanks again Mike! 
Neat little thing...it's already told me one of my coils I have in my speaker crossover stash is worthless.   Icon_eek
#29

It's just trying to make you toss all your coils and buy new one made in China. Cause it itself is made in China. Icon_mrgreen

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#30

(04-17-2019, 01:39 PM)morzh Wrote:  It's just trying to make you toss all your coils and buy new one made in China. Cause it itself is made in China. Icon_mrgreen

Oddly-enough, that is not true for these specific coils....these were probably wound right at the location
where I bought them from : Highland Heights, Ohio.  This one , I thought, was around .5mH,  but turned out to be .28 mH. ( I say 'thought' because I've removed wire from it in a guessing game). This resulting value would only be good for a crossover point of about 5kHz , . . . too high for my preference.

But your point is well-taken.  :-)  I know a few capitalists that are not beyond such things.

Surely, you're not suggesting these little cardboardy ones in the radios were  made in China in 1939 either.  Icon_evil 

The new  IF transformer  I bought as a possible replacement has an fragrance of Moo Goo Gai Pan, oh_yeah and measures  8.22 mH for the primary, and .185 mH for the secondary.... sure hope that secondary is high enough.  It's tiny.


Attached Files Image(s)
   




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
Road Trip for a Philco 46-480
Good morning, folks! I’ve finished the cabinet and the electrical restoration, and have detailed those in their respecti...jrblasde — 10:56 AM
Studebaker/Philco AC-2687 car radio
Arran, Thanks for checking you manuals. I appreciate that. Let me know what you find. PhilPdouglaski — 08:46 AM
Studebaker/Philco AC-2687 car radio
I have some car radio service manuals, Riders I think (not to be confused with the big blue binders), so I may see if on...Arran — 01:20 AM
Philco model 40-100
Greetings; Here is an update, I found a listing on fleabay for a similar chassis to yours, and it has a photo of what...Arran — 12:58 AM
Philco model 40-100
Greetings; I think I may have found a clue as to what is missing, from a search I made, there is a rear view of the c...Arran — 12:12 AM
Philco model 40-100
I recently acquired a Philco model 40-100 farm (battery) radio. The radio was in very good condition except the red on f...mhamby — 05:59 PM
Studebaker/Philco AC-2687 car radio
Hello, Richard the radio is an AC-2687 Studebaker model. The Philco model is S -5323 and the chassis p/n is S-5523Pdouglaski — 11:52 AM
48-482 rear panel help
The 48-482 is an AC only set as well, featuring a power transformer. While the transformer shouldn’t get “hot”, it is ye...jrblasde — 11:12 AM
Studebaker/Philco AC-2687 car radio
I gave a Chrysler/MoPar car radio from 1954, it was made by Philco, and it uses two chassis, one has the power supply an...Arran — 11:06 AM
48-482 rear panel help
Hello keithchip. You could make a hardboard back for the set, but make sure you provide plenty of ventilation holes in ...GarySP — 11:04 AM

[-]
Who's Online
There are currently 2164 online users. [Complete List]
» 3 Member(s) | 2161 Guest(s)
AvatarAvatarAvatar

>