Hi All, has anybody out there in radio land rewound an AK model E speaker coil? I have one that is bad and was kinda wondering if it is doable or it will need to be sent in. Also what kind off ohms readings should I have on it, it is OL at the moment. Thanks George

Geroge

Coils are wound with very fine wire, around #40. Did you check ends of your coil? Maybe broken there? Some coils have two sections. Maybe one section is ok. One section alone will work.

Just measured a couple coils. One read 466 and the other 660 ohms. So there are differences. If you are going to rewind a coil fill the spool with #40 wire and regardless of resistance it will woek.

Norm

:Hi All, has anybody out there in radio land rewound an AK model E speaker coil? I have one that is bad and was kinda wondering if it is doable or it will need to be sent in. Also what kind off ohms readings should I have on it, it is OL at the moment. Thanks George
:

:Geroge
:
: Coils are wound with very fine wire, around #40. Did you check ends of your coil? Maybe broken there? Some coils have two sections. Maybe one section is ok. One section alone will work.
:
: Just measured a couple coils. One read 466 and the other 660 ohms. So there are differences. If you are going to rewind a coil fill the spool with #40 wire and regardless of resistance it will woek.
:
:Norm

High Again Norm, This is just a 2 wire coil one in and one out. I do have a roll of 34 guage enamelded wire do you think that would work? Thanks Again, George T

:
::Hi All, has anybody out there in radio land rewound an AK model E speaker coil? I have one that is bad and was kinda wondering if it is doable or it will need to be sent in. Also what kind off ohms readings should I have on it, it is OL at the moment. Thanks George
::
:
:

George

Number 34 will be heavier than original wire. You won't be able to get as many turns on the spool.

Here is something I think will work but never tried. Use a heavier wire with fewer turns and a matching output transformer. Modern speakers are built this way.

Norm

::Geroge
::
:: Coils are wound with very fine wire, around #40. Did you check ends of your coil? Maybe broken there? Some coils have two sections. Maybe one section is ok. One section alone will work.
::
:: Just measured a couple coils. One read 466 and the other 660 ohms. So there are differences. If you are going to rewind a coil fill the spool with #40 wire and regardless of resistance it will woek.
::
::Norm
:
:High Again Norm, This is just a 2 wire coil one in and one out. I do have a roll of 34 guage enamelded wire do you think that would work? Thanks Again, George T
:
:
:
::
:::Hi All, has anybody out there in radio land rewound an AK model E speaker coil? I have one that is bad and was kinda wondering if it is doable or it will need to be sent in. Also what kind off ohms readings should I have on it, it is OL at the moment. Thanks George
:::
::
::
:
:

Geo,
I rewound a G-G Majestic (circa 1929) speaker and it took 15,000ft of #32 to get close to original DC resistance specified. Most will say it's not critical, but make sure you have enough wire to get close.

marv

::Geroge
::
:: Coils are wound with very fine wire, around #40. Did you check ends of your coil? Maybe broken there? Some coils have two sections. Maybe one section is ok. One section alone will work.
::
:: Just measured a couple coils. One read 466 and the other 660 ohms. So there are differences. If you are going to rewind a coil fill the spool with #40 wire and regardless of resistance it will woek.
::
::Norm
:
:High Again Norm, This is just a 2 wire coil one in and one out. I do have a roll of 34 guage enamelded wire do you think that would work? Thanks Again, George T
:
:
:
::
:::Hi All, has anybody out there in radio land rewound an AK model E speaker coil? I have one that is bad and was kinda wondering if it is doable or it will need to be sent in. Also what kind off ohms readings should I have on it, it is OL at the moment. Thanks George
:::
::
::
:
:

Marv

Was that for a horseshoe magnet or field? Don't see how 15,000 feet would fit on an AK coil form?

George has #34 wire. According to wire tables 1000 feet is 260 ohms. It takes at least twice that. Number 40 wire has 1049 ohms per 1000 feet.

Norm

:Geo,
:I rewound a G-G Majestic (circa 1929) speaker and it took 15,000ft of #32 to get close to original DC resistance specified. Most will say it's not critical, but make sure you have enough wire to get close.
:
:marv
:
:::Geroge
:::
::: Coils are wound with very fine wire, around #40. Did you check ends of your coil? Maybe broken there? Some coils have two sections. Maybe one section is ok. One section alone will work.
:::
::: Just measured a couple coils. One read 466 and the other 660 ohms. So there are differences. If you are going to rewind a coil fill the spool with #40 wire and regardless of resistance it will woek.
:::
:::Norm
::
::High Again Norm, This is just a 2 wire coil one in and one out. I do have a roll of 34 guage enamelded wire do you think that would work? Thanks Again, George T
::
::
::
:::
::::Hi All, has anybody out there in radio land rewound an AK model E speaker coil? I have one that is bad and was kinda wondering if it is doable or it will need to be sent in. Also what kind off ohms readings should I have on it, it is OL at the moment. Thanks George
::::
:::
:::
::
::
:
:

Norm,
It was a round core completely removable from the frame. As a matter of fact, the entire speaker could be disassembled, including cone with attached voice coil. Never seen anything like it since. Yes it was a 4 day ritual of 1 hour winding, (hand guided,) on a special jig I improvised, with cig breaks in between. That was 9 yrs ago, but as I recall, DC resistance was spec'd at approx. 2500 ohms, and by calcs amounted to almost 3 miles of wire, which I measured with a digital mike to be #32. It worked great, but cathode resistor (WW) in the finals had an open, which I twisted together to get it up and running. I think from memory my numbers are correct, but feel free to respond.

marv

:Marv
:
: Was that for a horseshoe magnet or field? Don't see how 15,000 feet would fit on an AK coil form?
:
: George has #34 wire. According to wire tables 1000 feet is 260 ohms. It takes at least twice that. Number 40 wire has 1049 ohms per 1000 feet.
:
:Norm
:
::Geo,
::I rewound a G-G Majestic (circa 1929) speaker and it took 15,000ft of #32 to get close to original DC resistance specified. Most will say it's not critical, but make sure you have enough wire to get close.
::
::marv
::
::::Geroge
::::
:::: Coils are wound with very fine wire, around #40. Did you check ends of your coil? Maybe broken there? Some coils have two sections. Maybe one section is ok. One section alone will work.
::::
:::: Just measured a couple coils. One read 466 and the other 660 ohms. So there are differences. If you are going to rewind a coil fill the spool with #40 wire and regardless of resistance it will woek.
::::
::::Norm
:::
:::High Again Norm, This is just a 2 wire coil one in and one out. I do have a roll of 34 guage enamelded wire do you think that would work? Thanks Again, George T
:::
:::
:::
::::
:::::Hi All, has anybody out there in radio land rewound an AK model E speaker coil? I have one that is bad and was kinda wondering if it is doable or it will need to be sent in. Also what kind off ohms readings should I have on it, it is OL at the moment. Thanks George
:::::
::::
::::
:::
:::
::
::
:
:

Marv

That is quite a job. You must have made a nice jig to wind the coil in 4 hours. 4 days at 1 hour each.

The one George needs to wind is very small, maybe 1/2" in diameter. It's used on an Atwater Kent E series speaker.

Some day I would like to wind one of these coils with heavier wire, maybe 32 or 34. Then try the speaker with matching transformer. Should work and is much easier to wind than #40 or whatever AK used.

Norm

:Norm,
:It was a round core completely removable from the frame. As a matter of fact, the entire speaker could be disassembled, including cone with attached voice coil. Never seen anything like it since. Yes it was a 4 day ritual of 1 hour winding, (hand guided,) on a special jig I improvised, with cig breaks in between. That was 9 yrs ago, but as I recall, DC resistance was spec'd at approx. 2500 ohms, and by calcs amounted to almost 3 miles of wire, which I measured with a digital mike to be #32. It worked great, but cathode resistor (WW) in the finals had an open, which I twisted together to get it up and running. I think from memory my numbers are correct, but feel free to respond.
:
:marv
:
::Marv
::
:: Was that for a horseshoe magnet or field? Don't see how 15,000 feet would fit on an AK coil form?
::
:: George has #34 wire. According to wire tables 1000 feet is 260 ohms. It takes at least twice that. Number 40 wire has 1049 ohms per 1000 feet.
::
::Norm
::
:::Geo,
:::I rewound a G-G Majestic (circa 1929) speaker and it took 15,000ft of #32 to get close to original DC resistance specified. Most will say it's not critical, but make sure you have enough wire to get close.
:::
:::marv
:::
:::::Geroge
:::::
::::: Coils are wound with very fine wire, around #40. Did you check ends of your coil? Maybe broken there? Some coils have two sections. Maybe one section is ok. One section alone will work.
:::::
::::: Just measured a couple coils. One read 466 and the other 660 ohms. So there are differences. If you are going to rewind a coil fill the spool with #40 wire and regardless of resistance it will woek.
:::::
:::::Norm
::::
::::High Again Norm, This is just a 2 wire coil one in and one out. I do have a roll of 34 guage enamelded wire do you think that would work? Thanks Again, George T
::::
::::
::::
:::::
::::::Hi All, has anybody out there in radio land rewound an AK model E speaker coil? I have one that is bad and was kinda wondering if it is doable or it will need to be sent in. Also what kind off ohms readings should I have on it, it is OL at the moment. Thanks George
::::::
:::::
:::::
::::
::::
:::
:::
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:
:

Norm,
Cardboard core was approx 3" OD x 1" ID. Several 1 hour winding shifts thru-out the 4 days. The fixture was made from wood with an electric ice cream maker motor/transmission attached to side (.jpgs avail on request) Bearing supported supply reel attached above winding mechanism. About 1 rps for the core.

marv

:Marv
:
: That is quite a job. You must have made a nice jig to wind the coil in 4 hours. 4 days at 1 hour each.
:
: The one George needs to wind is very small, maybe 1/2" in diameter. It's used on an Atwater Kent E series speaker.
:
: Some day I would like to wind one of these coils with heavier wire, maybe 32 or 34. Then try the speaker with matching transformer. Should work and is much easier to wind than #40 or whatever AK used.
:
:Norm
:
:
:
:
::Norm,
::It was a round core completely removable from the frame. As a matter of fact, the entire speaker could be disassembled, including cone with attached voice coil. Never seen anything like it since. Yes it was a 4 day ritual of 1 hour winding, (hand guided,) on a special jig I improvised, with cig breaks in between. That was 9 yrs ago, but as I recall, DC resistance was spec'd at approx. 2500 ohms, and by calcs amounted to almost 3 miles of wire, which I measured with a digital mike to be #32. It worked great, but cathode resistor (WW) in the finals had an open, which I twisted together to get it up and running. I think from memory my numbers are correct, but feel free to respond.
::
::marv
::
:::Marv
:::
::: Was that for a horseshoe magnet or field? Don't see how 15,000 feet would fit on an AK coil form?
:::
::: George has #34 wire. According to wire tables 1000 feet is 260 ohms. It takes at least twice that. Number 40 wire has 1049 ohms per 1000 feet.
:::
:::Norm
:::
::::Geo,
::::I rewound a G-G Majestic (circa 1929) speaker and it took 15,000ft of #32 to get close to original DC resistance specified. Most will say it's not critical, but make sure you have enough wire to get close.
::::
::::marv
::::
::::::Geroge
::::::
:::::: Coils are wound with very fine wire, around #40. Did you check ends of your coil? Maybe broken there? Some coils have two sections. Maybe one section is ok. One section alone will work.
::::::
:::::: Just measured a couple coils. One read 466 and the other 660 ohms. So there are differences. If you are going to rewind a coil fill the spool with #40 wire and regardless of resistance it will woek.
::::::
::::::Norm
:::::
:::::High Again Norm, This is just a 2 wire coil one in and one out. I do have a roll of 34 guage enamelded wire do you think that would work? Thanks Again, George T
:::::
:::::
:::::
::::::
:::::::Hi All, has anybody out there in radio land rewound an AK model E speaker coil? I have one that is bad and was kinda wondering if it is doable or it will need to be sent in. Also what kind off ohms readings should I have on it, it is OL at the moment. Thanks George
:::::::
::::::
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:

:Geo,
:I rewound a G-G Majestic (circa 1929) speaker and it took 15,000ft of #32 to get close to original DC resistance specified. Most will say it's not critical, but make sure you have enough wire to get close.
:
:marv

15 thousand feet???
That's about 3 MILES of wire!!!!
Seems like more wire than you could stuff into the whole radio.

Naw Peter, put it right back on the original core, with a lot of patience, and a special jig I improvised for just that job. Wire cost me $55, which is probably more than a G-G Majestic 90B is worth.

marv

::Geo,
::I rewound a G-G Majestic (circa 1929) speaker and it took 15,000ft of #32 to get close to original DC resistance specified. Most will say it's not critical, but make sure you have enough wire to get close.
::
::marv
:
:15 thousand feet???
: That's about 3 MILES of wire!!!!
:Seems like more wire than you could stuff into the whole radio.
:

This is a long shot: could there ever be a situation where a new, commercial spool of wire could be used as a replacement field coil? Is the inside winding typically brought out of the i.d. of the spool? If not, maybe the spool's inside diameter could be disected, and the end fished out?

Or, if the commercial spool's i.d. didn't match the original field coil's, could a magnetic core be added and physically mated to the original field coil's core?

Anything to avoid rewinding a couple of miles of wire.

Doug,
Well yes, if the core just happened to be the right size to fit the other hardware, and was plastic or cardboard (no metal). The reel I got was plastic and had flanges about 10" OD, with a 3" dia core, about 6" long. Far too large for my application. Field coils with low DC resistance would lead one to believe a small reel of wire would do the job, and might even have a plastic reel adaptable to the application, but that's a long shot. As a matter of fact, some FC's run hot, so plastic might not be wise. As noted in earlier post, this speaker was made up of individual pieces assembled together for the end product. The cone sat loosely in its basket, and was attached to it with semicircular straps/screws at the rim, but no glue. Of course shims were used during final assembly, before seating the strap/cone screws. I modified the motor/transmission assembly with an ON/OFF switch for local control without reaching for the line cord. I reasoned that a tangled wire/supply reel, and wire would break, which happened near the end with the last 500 ft of wire. The FC didn't know the difference, and speaker worked fine.

marv

:This is a long shot: could there ever be a situation where a new, commercial spool of wire could be used as a replacement field coil? Is the inside winding typically brought out of the i.d. of the spool? If not, maybe the spool's inside diameter could be disected, and the end fished out?
:
:Or, if the commercial spool's i.d. didn't match the original field coil's, could a magnetic core be added and physically mated to the original field coil's core?
:
:Anything to avoid rewinding a couple of miles of wire.
:

Here's another off-the-wall idea.

My wife's sewing machine is able to unspool thread and fill a bobbin. The speed of the transfer is controlled by the foot pedal. A fixture could be cobbled together to fit a spool of fine wire where the the spool of thread goes. Likewise, the form for the field coil could be fitted to the capstan where the empty bobbin normally goes.

Doug,
Don't think even #40 wire would behave the same as cotton thread. Certainly, on my machine, I can fill a bobbin in a matter of seconds with thread, but it would be far more difficult with wire. Remember my journey into a coil winding a while back. Primary goal was to produce lattice wound coils on forms of various diameter and length, and it seemed to work well with thread, but the left-over #32 from my FC effort didn't do so well. Even my elementary prototypes for FC's and lattice coils would be better suited than a sewing machine.

marv

:Here's another off-the-wall idea.
:
:My wife's sewing machine is able to unspool thread and fill a bobbin. The speed of the transfer is controlled by the foot pedal. A fixture could be cobbled together to fit a spool of fine wire where the the spool of thread goes. Likewise, the form for the field coil could be fitted to the capstan where the empty bobbin normally goes.
:

:Doug,
:Don't think even #40 wire would behave the same as cotton thread. Certainly, on my machine, I can fill a bobbin in a matter of seconds with thread, but it would be far more difficult with wire. Remember my journey into a coil winding a while back. Primary goal was to produce lattice wound coils on forms of various diameter and length, and it seemed to work well with thread, but the left-over #32 from my FC effort didn't do so well. Even my elementary prototypes for FC's and lattice coils would be better suited than a sewing machine.
:
:marv
:
::Here's another off-the-wall idea.
::
::My wife's sewing machine is able to unspool thread and fill a bobbin. The speed of the transfer is controlled by the foot pedal. A fixture could be cobbled together to fit a spool of fine wire where the the spool of thread goes. Likewise, the form for the field coil could be fitted to the capstan where the empty bobbin normally goes.
::
:
:
Hi All, just seen a Model E speaker go for $29.00 on Ebay. I think I should have bought it and saved what sounds to be a lot of work. LOL I'm hoping to take the coil apart tonight or tomorrow and see if it can be fixed rather than rewound. It's a very small coil so I probably will need some #40 wire to get the 500 ohms. Maybe I'll get lucky and be able to fix it. It is a very different type speaker the way it was assembled, only problem so far is everything is very tight I guess from not being moved in close to 80 years. First thing is to get the cone loose then I should be able to bare down on the rest to get it loose. Thanks Again, George