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

Replacement for .7 to 1 interstage transformer
#1

Had a similar thread, but it wasn’t as specific as this, and therefore got lost. Anyone know a good replacement for this interstage transformer? Has a turns ratio of .7 to 1. It’s in a Sparton 28.

[Image: https://i.imgur.com/lNO85AP.jpg]
#2

It can not be .7 to 1.
Just by the sheer DC resistance, even if accounted for the wire gauge, 700 Ohm to 1 Ohm means huge difference in the number of turns.

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.
#3

Morzh,

Look at the schematic. Primary at 3580Ω, secondary center-tapped at 2985Ω (or 5970Ω total secondary). equals a turns ratio of actually .599 to one, but close enough to the rated value of .7 to 1. Am I missing something here?
#4

Morzh,

Oh, I see. Your're looking at the output transformer. I'm referring to the input or interstage transformer.
#5

Oh..yes I was looking at the output.

38-116 has a similar one.
Lets' see if Tubes and More has something.
Nope. They have 1:2 and 1:3. Can't see that ratio around.
Maybe someone else can.

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.
#6

I found a 1:1.5 but that was the lowest. Did find a 1:1 but was discontinued.

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
#7

1:1.5 and 0.7 to 1 are close enough.

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.
#8

It's a Hammond 124D

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
#9

Great! Thanks Terry. I'll get a 124D and give it a shot.

Pat




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco 91 Restore Code ??
There is no such thing as bad Fluke. This said, they are expensive. A Fluke is easily 10x the price of comparable CCC...morzh — 05:45 PM
Philco 91 Restore Code ??
Hello Mike, Yes, I have 3 Fluke meters one being my first Fluke 77 and other being Fluke 87. My third is Fluke clamp -...radiorich — 05:04 PM
Philco 91 Restore Code ??
I knew that Fluke was the Cadillac so with that in mind what Fluke would you recommend I get?dconant — 03:53 PM
Philco 91 Restore Code ??
Yep. 10W is probably enough. Also, if the meter measures Farads, then it should also have that "Delta" button...morzh — 02:38 PM
Philco 91 Restore Code ??
I measured the current through the resistor I am using as a replacement for the speaker field coil and got 40ma. So that...dconant — 02:32 PM
Philco 91 Restore Code ??
No I'm not saying I don't own a DMM. I have a CCC one (Thsinde 18+). I forgot that could read caps. I did purchase a Flu...dconant — 02:28 PM
Philco 91 Restore Code ??
Are you telling me you do not own any decent DMM, that can measure capacitances from a few pF and up? Even todays CCC (C...morzh — 01:44 PM
Restoring Philco 96
Well, selectivity today, with stations disappearing, is not such a problem for TRF as it likely used to be. Although wh...morzh — 01:42 PM
Philco 91 Restore Code ??
Mike I did that already and can't really get any kind of reading. My little Honeytek A6013L reads 0 on all scales. One s...dconant — 01:38 PM
New member
Well, to be frank, when it comes to radios, especially the older types, a person with no electronic background could be ...morzh — 01:33 PM

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

>