Common Mode chokes will have three (or more) wires - they are designed to filter rF and reduce EMI (for the most part, not always).
Peter Wieck
Melrose Park, PA
A friend found a choke in his junk box and asked about it. I found one similar to it in mine. They are iron core chokes similar to the old
tube TV power supply section would have in it. They are probably over 50 years old and most likely came from an old TV set.
The question is why do they have 3 wires instead of 2 wires that the
other chokes I have seen have ?
I know they are not the output transformer of a push pull audio stage
that may have had the speaker wires cut off, but that is what they resemble.
What are the resistances?
In article <MPG.3b7227b6e9cda2ba113@news.plus.net>,
gravity@mjcoon.plus.com says...
A friend found a choke in his junk box and asked about it. I found one
similar to it in mine. They are iron core chokes similar to the old
tube TV power supply section would have in it. They are probably over 50 >> > years old and most likely came from an old TV set.
The question is why do they have 3 wires instead of 2 wires that the
other chokes I have seen have ?
I know they are not the output transformer of a push pull audio stage
that may have had the speaker wires cut off, but that is what they
resemble.
What are the resistances?
There seems to be one winding with a tap on it.
From one end to the other is about 280 ohms. From one end to another
wire is 272 ohms and the other is 8 ohms.
Again this is an iron core choke ? that is large enough to be used as a normal 2 wire power supply choke in a tube type TV set of the 1950's .
This sounds more like an transformer, with one contact common between
primary and secundary, than a choke.
Does it have an airgap in the core?
This sounds more like an transformer, with one contact common between primary and secundary, than a choke.
Does it have an airgap in the core?
There is no airgap that I can see. It could be an autotransformer.
While I am familiar with simple tube circuits, the old TV sets are
before my time so to speak. I would still like to see how it would be
used in an application.
There is no airgap that I can see. It could be an autotransformer.
While I am familiar with simple tube circuits, the old TV sets are
before my time so to speak. I would still like to see how it would be
used in an application.
** Could be a speaker transformer.
The TV set would have a live chassis.
There is no airgap that I can see. It could be an autotransformer.
While I am familiar with simple tube circuits, the old TV sets are
before my time so to speak. I would still like to see how it would be used in an application.
** Could be a speaker transformer.
The TV set would have a live chassis.
I am not familiar with that kind of speaker transformer. Are you saying
it is used in a method coming off the audio tube plate in a maner
similar to an autotransformer is used in power line circuits ?
It may make sense as there is a low resistance in series with a high resistance winding.
A friend found a choke in his junk box and asked about it. I found one >similar to it in mine. They are iron core chokes similar to the old
tube TV power supply section would have in it. They are probably over 50 >years old and most likely came from an old TV set.
The question is why do they have 3 wires instead of 2 wires that the
other chokes I have seen have ?
I know they are not the output transformer of a push pull audio stage
that may have had the speaker wires cut off, but that is what they
resemble.
A friend found a choke in his junk box and asked about it. I found one >similar to it in mine. They are iron core chokes similar to the old
tube TV power supply section would have in it. They are probably over 50 >years old and most likely came from an old TV set.
The question is why do they have 3 wires instead of 2 wires that the
other chokes I have seen have ?
I know they are not the output transformer of a push pull audio stage
that may have had the speaker wires cut off, but that is what they
resemble.
Autotransformer. If it were a single center tap winding, applying
120VAC between the tap and one common end, would produce 240VAC
between the common end and the other end. I suspect it's really old
as such an arrangement might be considered an electrocution hazard. <https://en.wikipedia.org/wiki/Autotransformer> <https://www.google.com/search?q=autotransformer&tbm=isch>
...All the E cores are facing
one direction and the I segments are all at one end instead of
alternating like most transformers.
Perhaps it's a tube heater (12 - 6V) range.
legg wrote more crap:
===================
Perhaps it's a tube heater (12 - 6V) range.
** Not with a source impedance of around 16 ohms.
...All the E cores are facing
one direction and the I segments are all at one end instead of
alternating like most transformers.
That shows it is designed to handle DC or a very asymmetrical waveform.
My guess would be a frame output autotransformer for driving the field
coils around the tube neck.
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