Hello, my friend brought over his Sparton model 557 for me to see why the SW was not working, the AM works just fine !
I discovered the secondary winding on the SW osc, coil, was open , the primary winding and the RF SW coil was good ! Where do I start looking for a replacement SW osc. coil, or someone interested in rewinding the original ? Unfortunately the secondary winding is below the primary , if you put the new secondary on top of the prinary , their is no way to count the turns on the secondary !
Thanks for any suggestions to my problem ,
Lee Petrie, Joliet, IL.

Whoever rebuilds this coil will probably just strip both windings off the core and start from scratch. That way the number of turns for each winding can be positively determined.

Since this is a SW band coil, it won't be that tough to rewind, having a much lower turns count than the associated BC band coil.

The three "tricks" in rewinding a coil are: (1) use the correct diameter wire; (2) wind the coils in the same direction (CW or CCW) as the original; and (3) keep the turns count same as the original.

If you manually rewind the coil, chances are the cosmetic result won't be pretty, but it will work fine.

Or perhaps a down and dirty fix may be to wind a number of turns into a coil and stuff inside the SW oscillator coil and connect to the terminals of the original winding. May have to reverse the connections and experiment with the number of turns.

Clifton

:Whoever rebuilds this coil will probably just strip both windings off the core and start from scratch. That way the number of turns for each winding can be positively determined.
:
:Since this is a SW band coil, it won't be that tough to rewind, having a much lower turns count than the associated BC band coil.
:
:The three "tricks" in rewinding a coil are: (1) use the correct diameter wire; (2) wind the coils in the same direction (CW or CCW) as the original; and (3) keep the turns count same as the original.
:
:If you manually rewind the coil, chances are the cosmetic result won't be pretty, but it will work fine.
:

Thanks for the re-winding thoughts , if I try to find a replacement , where might I start looking for a cross-reference list , translating which Meissner, Miller , ect.,coil might sub for my "open" Sparton SW osc. coil ?
Another thought , could I use "any" generic / after-market, 4 lug, SW Osc. coil, to sub in directly ( without change ) for my open coil , even if the original DOESN'T have any adjustment trimmer ?
Thanks again for your help, Lee Petrie , Joliet, IL.

:Or perhaps a down and dirty fix may be to wind a number of turns into a coil and stuff inside the SW oscillator coil and connect to the terminals of the original winding. May have to reverse the connections and experiment with the number of turns.
:
:Clifton
:
::Whoever rebuilds this coil will probably just strip both windings off the core and start from scratch. That way the number of turns for each winding can be positively determined.
::
::Since this is a SW band coil, it won't be that tough to rewind, having a much lower turns count than the associated BC band coil.
::
::The three "tricks" in rewinding a coil are: (1) use the correct diameter wire; (2) wind the coils in the same direction (CW or CCW) as the original; and (3) keep the turns count same as the original.
::
::If you manually rewind the coil, chances are the cosmetic result won't be pretty, but it will work fine.
::
:
:

Generally the secondary or the unturned winding was not too critical. Just for kicks might wind some turns of wire about the same size as the original winding around the coil and attach to the connections of the open winding and see what happens. May have to reverse the connections.

Clifton

: Thanks for the re-winding thoughts , if I try to find a replacement , where might I start looking for a cross-reference list , translating which Meissner, Miller , ect.,coil might sub for my "open" Sparton SW osc. coil ?
: Another thought , could I use "any" generic / after-market, 4 lug, SW Osc. coil, to sub in directly ( without change ) for my open coil , even if the original DOESN'T have any adjustment trimmer ?
: Thanks again for your help, Lee Petrie , Joliet, IL.
:
::Or perhaps a down and dirty fix may be to wind a number of turns into a coil and stuff inside the SW oscillator coil and connect to the terminals of the original winding. May have to reverse the connections and experiment with the number of turns.
::
::Clifton
::
:::Whoever rebuilds this coil will probably just strip both windings off the core and start from scratch. That way the number of turns for each winding can be positively determined.
:::
:::Since this is a SW band coil, it won't be that tough to rewind, having a much lower turns count than the associated BC band coil.
:::
:::The three "tricks" in rewinding a coil are: (1) use the correct diameter wire; (2) wind the coils in the same direction (CW or CCW) as the original; and (3) keep the turns count same as the original.
:::
:::If you manually rewind the coil, chances are the cosmetic result won't be pretty, but it will work fine.
:::
::
::
:
:

Thanks for your continuing interest in my SW osc. open sec. post, Clifton ! I'm very concerned not to just "start riping off the old windings" , on my personal friend's , high dollar Sparton #557 , your suggest might be the "middle road" , doing something, but not going "hog wild" ! ( That was the name of a Laural & Hardy movie, about puting up a radio antenna, their way ! )
Another thought that I had , talking about "experimenting", do you feel it might be worth the time to "jumper-in" a SW OSC. COIL from another (BRAND) of radio or a NEW , like a Meissner , ect. , after-market SW OSC COIL replacement ! I personally have rewound a few types of Philco coils , on my OWN radios, in the past, but totally destroy the SW reception forever, by starting from a bare core, is very concerning to me , that is why your suggestion make more sence to me ! Lee Petrie, Joliet, IL.

:Generally the secondary or the unturned winding was not too critical. Just for kicks might wind some turns of wire about the same size as the original winding around the coil and attach to the connections of the open winding and see what happens. May have to reverse the connections.
:
:Clifton
:
:
:: Thanks for the re-winding thoughts , if I try to find a replacement , where might I start looking for a cross-reference list , translating which Meissner, Miller , ect.,coil might sub for my "open" Sparton SW osc. coil ?
:: Another thought , could I use "any" generic / after-market, 4 lug, SW Osc. coil, to sub in directly ( without change ) for my open coil , even if the original DOESN'T have any adjustment trimmer ?
:: Thanks again for your help, Lee Petrie , Joliet, IL.
::
:::Or perhaps a down and dirty fix may be to wind a number of turns into a coil and stuff inside the SW oscillator coil and connect to the terminals of the original winding. May have to reverse the connections and experiment with the number of turns.
:::
:::Clifton
:::
::::Whoever rebuilds this coil will probably just strip both windings off the core and start from scratch. That way the number of turns for each winding can be positively determined.
::::
::::Since this is a SW band coil, it won't be that tough to rewind, having a much lower turns count than the associated BC band coil.
::::
::::The three "tricks" in rewinding a coil are: (1) use the correct diameter wire; (2) wind the coils in the same direction (CW or CCW) as the original; and (3) keep the turns count same as the original.
::::
::::If you manually rewind the coil, chances are the cosmetic result won't be pretty, but it will work fine.
::::
:::
:::
::
::
:
:

How you proceed with the repair depends on the results that you hope to achieve.

Carefully rewinding the coil "from scratch" offers the best chance for getting the indicator needle to track the dial calibration. Trying to kludge in a repair or guess at a substitute coil may allow the set to pick up some stations, but the likelihood that the radio could be accurately aligned on the SW band seems low. But, maybe that is of no consequence to the present owner.

At any rate, trying something and failing won't damage the set any more than it already is (assuming that the repair strategy you choose doesn't involve charcoal and lighter fluid). Probably the best approach is to pick a repair plan that will not give a future owner of this set a reason to curse you out by introducing a "user mod" that the schematic doesn't cover.

Hi CV ,
You are right on the money, BEFORE I make any move at this end, I will make contact with the Sparton's owner, to best follow his wishes ! A very good point about changing the appearance of different "looking parts" under the chassis from what the schematics describes , I alway give the radio's owner, schematics showing the changes , like solid state diodes and extra resistors, in lew of the 6X5(s) in Zeniths ! The bottom line , it is his choice , thanks again for your directions,
Lee Petrie, Joliet, IL.

you proceed with the repair depends on the results that you hope to achieve.
:
:Carefully rewinding the coil "from scratch" offers the best chance for getting the indicator needle to track the dial calibration. Trying to kludge in a repair or guess at a substitute coil may allow the set to pick up some stations, but the likelihood that the radio could be accurately aligned on the SW band seems low. But, maybe that is of no consequence to the present owner.
:
:At any rate, trying something and failing won't damage the set any more than it already is (assuming that the repair strategy you choose doesn't involve charcoal and lighter fluid). Probably the best approach is to pick a repair plan that will not give a future owner of this set a reason to curse you out by introducing a "user mod" that the schematic doesn't cover.
: