In article ,
says...



Hi John ... well you found him ... actually a friend of mine had them
wound ... for his E-155 and my E-155 and a few spare parts ... and yes
my buddy Kim Herron has a couple cores rewound that are left... he had
the transformer company in Grand Rapids, Michigan rewind them for us..

and yes its a 3 winding arrangement... nothing like a normal transformer..
so do you have your iron core?

John k9uwa


I have seen several posts in rec.antiques.radio+phono over the years
from people who have rewound the GE "transformers", although I don't
remember who they were from.
John Byrns

John Byrns wrote:

OK, I see we are going in opposite directions on the coupling effect.
If the coupling were perfect when the core is not saturated, then the
light would be as bright as it could get due to the bucking effect of
the two windings.

Right - up to the "as it could get" with the core NOT saturated - then
the coupling is good - the windings buck - bulb dim.


When the transformer becomes saturated decreasing the
coupling, the brightness would have nowhere to go but down due the
residual inductance remaining in the two coils.

This is where you go off track - when the core saturates two things
happen - the inductance of the coils drops through the floor - less
inductance - higher current. The coupling also starts to fail as well -
so the bucking effect also decreases - bulb brighter...


News Flash, I am really liking the theory I advanced a few messages ago
that the "transformer" is not wound like an ordinary transformer, but
instead has one of the secondaries wound on each outside leg of the
E-core.

Not news - this would be common for a saturable reactor.

The reason I am really liking this theory now is that I looked up the
service data for the General Electric E-155 which has the similar
Colorama tuning system, and the "transformer" is constructed exactly as
I speculated in my earlier message. If the S-W "transformer" is built
the same way then it is a whole new ball game.

Why? If in fact (as I've postulated most recently) that reactance is
indeed the greater control factor - then whether one coil of the two is
reversed or not would only effect the linearity of the control, not that
it works. I looked up a few site - and found a couple interesting ones...

http://www.allaboutcircuits.com/vol_2/chpt_9/7.html

Down towards the bottom of the page - just above the Scott-T. Notice
that in the final example - they reverse one of the two control windings
- the same thing would be accomplished by leaving the control windings
in phase and reversing the the load winding... Here they use two
reactors to accomplish symmetry - here is a way to do it with one:

http://www.tpub.com/content/neets/14.../14180_137.htm
note that this is the first of several pages - you'll have to page
through them to get to the main point. Notice that by the time they get
to the three legged configuration - (and torrids) - the load windings
are opposed to provide symmetry.

Again not knowing the construction of the S/W transformer leaves some
guessing - but as I noted before - if all three windings are wound on a
C form - then bucking may be a significant part of the control
equation - if three legged on an E core (I doubt torrids were in use
back then) - then bucking would not be significant (as that coupling
would be minor compared to the reactance change).

best regards...
--
randy guttery

A Tender Tale - a page dedicated to those Ships and Crews
so vital to the United States Silent Service:
http://tendertale.com

Randy or Sherry Guttery wrote:

a bunch of stuff...

Let me add a point... when I originally looked at the schematic - the
saturable reactor was drawn as a transformer - though it didn't take
long to figure out that it had to be a form of saturable reactor rather
than a transformer... (being an early schematic, I doubt the "standard"
for indicating saturable reactors had been established, and certainly
not yet in common use).

That only leaves figuring out whether the S/W is a two or three legged
configuration (are the two load windings on the same leg). As noted - a
picture might tell a lot. Also - note that the GE version is a fully
buffered (isolated) and driven system - while the S/W's system is part
of the RF / IF B+... the differences make a significant impact on how
the two circuits act (and interact)...

best regards...
--
randy guttery

A Tender Tale - a page dedicated to those Ships and Crews
so vital to the United States Silent Service:
http://tendertale.com

In article 3Njai.154612$_c5.5197@attbi_s22,
TUFF (John Goller, k9uwa) wrote:

In article ,
says...

Hi John ... well you found him ... actually a friend of mine had them
wound ... for his E-155 and my E-155 and a few spare parts ... and yes
my buddy Kim Herron has a couple cores rewound that are left... he had
the transformer company in Grand Rapids, Michigan rewind them for us..

and yes its a 3 winding arrangement... nothing like a normal transformer..
so do you have your iron core?

Hi John,

It's not my radio, Randy and I were simply discussing over on
alt.binaries.pictures.radio how the "Stewart-Warner reactance dimmer"
might actually work. This discussion is the result of a post by "Dave
Burson" on alt.binaries.pictures.radio who has a S-W model R-1822 with
an open primary on the reactance control "transformer". I cross posted
the discussion here because I remembered that someone here had talked
about fixing a similar problem on a GE set before. Dave hasn't
responded yet with any information on the physical construction of the
S-W "transformer", whether it's construction is similar to the GE
"transformer" or is different.


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

In article , Ken
wrote:

John Byrns wrote:
In article ,
Randy or Sherry Guttery wrote:

John Byrns wrote:

Is one or the other really necessarily a "bonus", don't they work in
opposite directions assuming the two windings are connected in a
"bucking" configuration?
No - because "bucking" would be dependent on good coupling... Which
happens when the core is NOT saturated - so saturated - not bucking -
bright.

OK, I see we are going in opposite directions on the coupling effect.
If the coupling were perfect when the core is not saturated, then the
light would be as bright as it could get due to the bucking effect of
the two windings. When the transformer becomes saturated decreasing the
coupling, the brightness would have nowhere to go but down due the
residual inductance remaining in the two coils.

So coupling drops when saturated - so saturated - low coupling - dim

This works against the reactance effect you describe below.

Reactance drops when saturated - so saturated - low reactance - bright.

News Flash, I am really liking the theory I advanced a few messages ago
that the "transformer" is not wound like an ordinary transformer, but
instead has one of the secondaries wound on each outside leg of the
E-core.

The reason I am really liking this theory now is that I looked up the
service data for the General Electric E-155 which has the similar
Colorama tuning system, and the "transformer" is constructed exactly as
I speculated in my earlier message. If the S-W "transformer" is built
the same way then it is a whole new ball game.

Of course we don't actually know they are
really connected in a "bucking" configuration, we are just speculating
they are because of the way the schematic is drawn.
I'd be VERY surprised if they are not... 1) why have two windings if
"bucking" (or as I speculated previously -- phase reversal to provide
symmetry) was not needed? 2) why take the extra effort to draw the
schematic that way?

See above.

I'm glad you are the one working all this out, I would like to see more
information on the construction of the transformer and the disposition
of the windings before speculating too much. If the transformer is of
open frame construction and is not potted, the OP should be able to
easily determine if an E-core is used and if all the windings are on the
center leg?
Since I don't have "hands on" access - I am left with few options: 1)
guess. 2) offer to see if I can fix the thing. (did I really say that???).

The thing that bothers me about that is if the laminations (assuming
(that dangerous word!) traditional construction) are welded... it might
be extremely tough to get it apart to get at the bobbins... Yes
pictures worth 1K words...

I have seen several posts in rec.antiques.radio+phono over the years
from people who have rewound the GE "transformers", although I don't
remember who they were from.


Regards,

John Byrns

Byrns wrote: OK, I see we are going in opposite directions on the
coupling effect.
If the coupling were perfect when the core is not saturated, then the
light would be as bright as it could get due to the bucking effect of
the two windings.

NO. If the coupling were perfect, the light would be dim because the two
windings are bucking their max., preventing current flow to the lamp. Ken

NO, assuming there is no saturation in the core and the coupling is
perfect the reactance of the two windings connected to "buck" would be
very low and the light would be bright, if they are connected to aid
then the total reactance would be four times the reactance of a single
winding and the light would be dim. When we are talking about "perfect"
coupling we are simply talking about a choke with two windings and
considering what the reactance the two series connected windings would
be with the two possible phasing connections.


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

John Byrns wrote:

NO, assuming there is no saturation in the core and the coupling is
perfect the reactance of the two windings connected to "buck" would be
very low and the light would be bright, if they are connected to aid
then the total reactance would be four times the reactance of a single
winding and the light would be dim. When we are talking about "perfect"
coupling we are simply talking about a choke with two windings and
considering what the reactance the two series connected windings would
be with the two possible phasing connections.

Now you've lost me - if there is no saturation - then reactance is max -
regardless of "phasing"... particularly in a three-legged config. (where
coupling is insignificant). The only effect phasing would have would be
symmetrical control - and particularly with an E config. cancellation of
the induced AC field before it combines with (to aid or buck) the
control field.

What am I missing?????

best regards...
--
randy guttery

A Tender Tale - a page dedicated to those Ships and Crews
so vital to the United States Silent Service:
http://tendertale.com

John,

I did post another wiring illustration from the schematic page on the
binaries. Please have a look and see whether it clarifies anything. I will
post a photo of the x-former in place, though I doubt it's of much help.
Thanks.

Dave

"John Byrns" wrote in message
...
In article 3Njai.154612$_c5.5197@attbi_s22,
TUFF (John Goller, k9uwa) wrote:

In article ,
says...

Hi John ... well you found him ... actually a friend of mine had them
wound ... for his E-155 and my E-155 and a few spare parts ... and yes
my buddy Kim Herron has a couple cores rewound that are left... he had
the transformer company in Grand Rapids, Michigan rewind them for us..

and yes its a 3 winding arrangement... nothing like a normal
transformer..
so do you have your iron core?

Hi John,

It's not my radio, Randy and I were simply discussing over on
alt.binaries.pictures.radio how the "Stewart-Warner reactance dimmer"
might actually work. This discussion is the result of a post by "Dave
Burson" on alt.binaries.pictures.radio who has a S-W model R-1822 with
an open primary on the reactance control "transformer". I cross posted
the discussion here because I remembered that someone here had talked
about fixing a similar problem on a GE set before. Dave hasn't
responded yet with any information on the physical construction of the
S-W "transformer", whether it's construction is similar to the GE
"transformer" or is different.


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

Here is a photo and a repost of the connection diagram. Note the unused
center terminal at the top and at the bottom. Primariy connections are at
top an can be seen in the photo.

I'm glad you are the one working all this out, I would like to see more
information on the construction of the transformer and the disposition
of the windings before speculating too much. If the transformer is of
open frame construction and is not potted, the OP should be able to
easily determine if an E-core is used and if all the windings are on the
center leg?


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

Hi Dave,

Thanks for posting the photo, it makes clear that all three windings are
on the center leg of an E-core unlike the General Electric circuit. It
doesn't make it clear if the two "secondary" windings are connected in a
"bucking" configuration as the schematic implies, or in an "aiding"
configuration. With the open primary what is the voltage across the
light, is it the full heater supply voltage, approximately 6.3 volts, or
is it noticeably lower? This information would help explain how the two
windings are connected and how the circuit works.


Regards,

John Byrns


In article ,
"Dave Burson" wrote:

John,

I did post another wiring illustration from the schematic page on the
binaries. Please have a look and see whether it clarifies anything. I will
post a photo of the x-former in place, though I doubt it's of much help.
Thanks.

Dave

"John Byrns" wrote in message
...
In article 3Njai.154612$_c5.5197@attbi_s22,
TUFF (John Goller, k9uwa) wrote:

In article ,
says...

Hi John ... well you found him ... actually a friend of mine had them
wound ... for his E-155 and my E-155 and a few spare parts ... and yes
my buddy Kim Herron has a couple cores rewound that are left... he had
the transformer company in Grand Rapids, Michigan rewind them for us..

and yes its a 3 winding arrangement... nothing like a normal
transformer..
so do you have your iron core?

Hi John,

It's not my radio, Randy and I were simply discussing over on
alt.binaries.pictures.radio how the "Stewart-Warner reactance dimmer"
might actually work. This discussion is the result of a post by "Dave
Burson" on alt.binaries.pictures.radio who has a S-W model R-1822 with
an open primary on the reactance control "transformer". I cross posted
the discussion here because I remembered that someone here had talked
about fixing a similar problem on a GE set before. Dave hasn't
responded yet with any information on the physical construction of the
S-W "transformer", whether it's construction is similar to the GE
"transformer" or is different.


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

--
Surf my web pages at, http://fmamradios.com/

In article ,
Randy or Sherry Guttery wrote:

John Byrns wrote:

NO, assuming there is no saturation in the core and the coupling is
perfect the reactance of the two windings connected to "buck" would be
very low and the light would be bright, if they are connected to aid
then the total reactance would be four times the reactance of a single
winding and the light would be dim. When we are talking about "perfect"
coupling we are simply talking about a choke with two windings and
considering what the reactance the two series connected windings would
be with the two possible phasing connections.

Now you've lost me - if there is no saturation - then reactance is max -
regardless of "phasing"... particularly in a three-legged config. (where
coupling is insignificant). The only effect phasing would have would be
symmetrical control - and particularly with an E config. cancellation of
the induced AC field before it combines with (to aid or buck) the
control field.

What am I missing?????

Notice I said "When we are talking about 'perfect' coupling we are
simply talking about a choke with two windings and considering what the
reactance the two series connected windings would be with the two
possible phasing connections." The "perfect" coupling in this example
implies that all three windings are are on the center leg of the core,
and with the primary disconnected we have a simple choke with two equal
windings. Assuming the choke is perfect, the inductance is zero when
the two coils are connected in the series "bucking" configuration, and
is four times the inductance of one winding when they are connected in
series aiding. You can prove this by either measuring a two winding
choke, or by writing the loop voltage equations for both configurations.


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/