Hi All!
Came across a type of capacitor hoping some one can enlighten me as too what type it is, the best I can describe it, it appears too have a coil type tubular form with windings on each end, I'm assuming that the value is determined by the number of windings and the spacing between them, however I still have no idea as too what type they are?
Mark

Mark: a coil usually suggests an inductor or choke, not a capacitor. Can you point us to a schematic and where this device appears?

Cheez…. I had already precisely zeroed in on it being a lower value wirewound resistor of 120 ohms value 5% tolerance…consisting of 325 turns of #30 nichrome wound on the forms surface such that the conformal coating on its top would still create a profile view beneath it that suggested a spaced out coil winding beneath its surface, but there is one turn that was burnt open by overload such that the unit will test open, like a capacitor when ohmmed out.
As , mentioned , much more exacting info as to exact physical size of all of its integral component structuring , materials used in construction, any manufacture marking or color coding , colors of structure portions , turns in the “coil” plus spacing.
All necessary in exacting a more analytical estimation of the ???? on hand.
All of this considering that this is a one of a kind find that you cannot refer to as being used in a particular piece of equipment for tech reference as Doug suggested.

73’s de Edd

:Mark: a coil usually suggests an inductor or choke, not a capacitor. Can you point us to a schematic and where this device appears?

:
:Cheez…. I had already precisely zeroed in on it being a lower value wirewound resistor of 120 ohms value 5% tolerance…consisting of 325 turns of #30 nichrome wound on the forms surface such that the conformal coating on its top would still create a profile view beneath it that suggested a spaced out coil winding beneath its surface, but there is one turn that was burnt open by overload such that the unit will test open, like a capacitor when ohmmed out.
:As , mentioned , much more exacting info as to exact physical size of all of its integral component structuring , materials used in construction, any manufacture marking or color coding , colors of structure portions , turns in the “coil” plus spacing.
:All necessary in exacting a more analytical estimation of the ???? on hand.
:All of this considering that this is a one of a kind find that you cannot refer to as being used in a particular piece of equipment for tech reference as Doug suggested.
:
:73’s de Edd
:
:
:
:
:
:
::Mark: a coil usually suggests an inductor or choke, not a capacitor. Can you point us to a schematic and where this device appears?
Hi Doug & Edd
No, these are definitely capacitors, they are marked as such on the schematic, they are 20MMf, 26MMF, 47MMF and 6MMF, which as far as I can figure would be equal too 20Pf, 26Pf, 47Pf and 6Pf, thing is I've seen these used before, usually in radio Oscilator and TV Tuner Oscillator circuits, I'm just trying to determine what type they are. As Far as a schematic goes, there is not one on here for it, I have the SAMS, if you would like I can E Mail the section they are used in, in this particular case they are in a television tuner oscillator ckt.
Mark

I think I know what you're talking about. You're talking about tubular ceramic condensers. These are made by putting a thin metal film or foil on the inside and outside of a ceramic tube. Each "electrode" or "plate" sticks out one end of the tube and has a few turns of wire wound around it and soldered to it. These look similar to some "dog bone" style resistors. Color dots are usually used for coding. The color dot systems can be found here on the internet. These condensers are extremely reliable. Sometimes they are encased in a brown material, perhaps an epoxy of sorts, or some clay-like material.

Thomas

:I think I know what you're talking about. You're talking about tubular ceramic condensers. These are made by putting a thin metal film or foil on the inside and outside of a ceramic tube. Each "electrode" or "plate" sticks out one end of the tube and has a few turns of wire wound around it and soldered to it. These look similar to some "dog bone" style resistors. Color dots are usually used for coding. The color dot systems can be found here on the internet. These condensers are extremely reliable. Sometimes they are encased in a brown material, perhaps an epoxy of sorts, or some clay-like material.
:
:Thomas
Hi Thomas
Yep, thats exactly what they look like, now I know what they are, and I can tell you this also, NPO Ceramics will not work in place of them, so there must be something very special about these type of ceramic capcitors, I found this out the hard way, luckly I saved the originals and put them back in, wow! what a difference between the two types, wish I could find somewhere I could get some of these type capacitors, any ideas?
Mark

Mark,

Just curious, what is them make/model of the radio and which capacitor(s) are you referring to?

Gary W. Prutchick

::I think I know what you're talking about. You're talking about tubular ceramic condensers. These are made by putting a thin metal film or foil on the inside and outside of a ceramic tube. Each "electrode" or "plate" sticks out one end of the tube and has a few turns of wire wound around it and soldered to it. These look similar to some "dog bone" style resistors. Color dots are usually used for coding. The color dot systems can be found here on the internet. These condensers are extremely reliable. Sometimes they are encased in a brown material, perhaps an epoxy of sorts, or some clay-like material.
::
::Thomas
:Hi Thomas
: Yep, thats exactly what they look like, now I know what they are, and I can tell you this also, NPO Ceramics will not work in place of them, so there must be something very special about these type of ceramic capcitors, I found this out the hard way, luckly I saved the originals and put them back in, wow! what a difference between the two types, wish I could find somewhere I could get some of these type capacitors, any ideas?
:Mark
:

:Mark,
:
:Just curious, what is them make/model of the radio and which capacitor(s) are you referring to?
:
:Gary W. Prutchick
:
:::I think I know what you're talking about. You're talking about tubular ceramic condensers. These are made by putting a thin metal film or foil on the inside and outside of a ceramic tube. Each "electrode" or "plate" sticks out one end of the tube and has a few turns of wire wound around it and soldered to it. These look similar to some "dog bone" style resistors. Color dots are usually used for coding. The color dot systems can be found here on the internet. These condensers are extremely reliable. Sometimes they are encased in a brown material, perhaps an epoxy of sorts, or some clay-like material.
:::
:::Thomas
::Hi Thomas
:: Yep, thats exactly what they look like, now I know what they are, and I can tell you this also, NPO Ceramics will not work in place of them, so there must be something very special about these type of ceramic capcitors, I found this out the hard way, luckly I saved the originals and put them back in, wow! what a difference between the two types, wish I could find somewhere I could get some of these type capacitors, any ideas?
::Mark
::Hi Gary
Its actually a VHF tuner in a television set, thats where these particular capcitors are, the Model Is 23G22/23G23 Zenith.
Mark

Mark, I have replaced them with silver mica caps and they work just fine.
Greg

::I think I know what you're talking about. You're talking about tubular ceramic condensers. These are made by putting a thin metal film or foil on the inside and outside of a ceramic tube. Each "electrode" or "plate" sticks out one end of the tube and has a few turns of wire wound around it and soldered to it. These look similar to some "dog bone" style resistors. Color dots are usually used for coding. The color dot systems can be found here on the internet. These condensers are extremely reliable. Sometimes they are encased in a brown material, perhaps an epoxy of sorts, or some clay-like material.
::
::Thomas
:Hi Thomas
: Yep, thats exactly what they look like, now I know what they are, and I can tell you this also, NPO Ceramics will not work in place of them, so there must be something very special about these type of ceramic capcitors, I found this out the hard way, luckly I saved the originals and put them back in, wow! what a difference between the two types, wish I could find somewhere I could get some of these type capacitors, any ideas?
:Mark
:

:Mark, I have replaced them with silver mica caps and they work just fine.
:Greg
:
:::I think I know what you're talking about. You're talking about tubular ceramic condensers. These are made by putting a thin metal film or foil on the inside and outside of a ceramic tube. Each "electrode" or "plate" sticks out one end of the tube and has a few turns of wire wound around it and soldered to it. These look similar to some "dog bone" style resistors. Color dots are usually used for coding. The color dot systems can be found here on the internet. These condensers are extremely reliable. Sometimes they are encased in a brown material, perhaps an epoxy of sorts, or some clay-like material.
:::
:::Thomas
::Hi Thomas
:: Yep, thats exactly what they look like, now I know what they are, and I can tell you this also, NPO Ceramics will not work in place of them, so there must be something very special about these type of ceramic capcitors, I found this out the hard way, luckly I saved the originals and put them back in, wow! what a difference between the two types, wish I could find somewhere I could get some of these type capacitors, any ideas?
::Mark
::Hi Greg
Thanks for the info, now at least i know of a suitable replacement type if I ever need them.
Mark

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Foul…Foul…it seems that the description and limited dimensional and shape info that you gave was in the order of the blind man’s description of the different aspects of an elephant from his perspective.. I was thinking of more “turns” being all across the caps body…but fortunately Thomas hit it right , in the respect of there only being 1-1/2 turns of wire to bond with the end caps being soldered on..
I just realized after that final supplication of the model and equipment that you are still on that Zenith that you learned about the futility in messing with the IF strip that was even initially in a proper operational state.
The same would hold true for the tuner and all of its caps. The most work typically needed on a tuner is a cleaning of contact wafers or strips of any oxide or debris and a thin coating of them with an anti oxidant . Then a peek inside at tubes plate and screen resistors for scorching in case there has been a shorted tuner tube present in the sets history. Be sure that prescribed tube shields are in place. That’s it.
Herewith is a zoom up of the units tuner…..within the realm of the threshold whereupon pixelation starts to inhibit definition.

http://img111.imageshack.us/img111/4375/zenithbwtnr7lz.jpg

Three tubular ceramic caps are viewable as a pair at C6,7 and the best view of one is C8. all of these were of what I called the ugly ones with their like conformal coatings . The smaller prettier ones would be the critical ones in the osc ckt as C17,18. Typically painted white with their color dots or slashes for color coding upon the cases, Or the very prettiest ones were some that retained their cases shiny silvering with the color codes laid on top of them.. I certainly hope that you have not touched them as they have special characteristics and anyway, are as fault free as a cap can be.
If a sets tuner/and/or/I.F. stage has experienced multiple random “experimental adjustments” ( that’s a definite downhill creating situation) the only way to obtain optimum performance again is to have a sweep and marker generator and be well versed on how to actually perform a sweep alignment. In the end one is to the point of micro adjustments of inductive and capacitive values , with each interacting with each other until a final proper response curve along with proper stage gain is attained.
P.S. C10 and C7 were red designated just to point out them as being ceramic piston variable caps.
73’s de Edd

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
::Mark, I have replaced them with silver mica caps and they work just fine.
::Greg
::
::::I think I know what you're talking about. You're talking about tubular ceramic condensers. These are made by putting a thin metal film or foil on the inside and outside of a ceramic tube. Each "electrode" or "plate" sticks out one end of the tube and has a few turns of wire wound around it and soldered to it. These look similar to some "dog bone" style resistors. Color dots are usually used for coding. The color dot systems can be found here on the internet. These condensers are extremely reliable. Sometimes they are encased in a brown material, perhaps an epoxy of sorts, or some clay-like material.
::::
::::Thomas
:::Hi Thomas
::: Yep, thats exactly what they look like, now I know what they are, and I can tell you this also, NPO Ceramics will not work in place of them, so there must be something very special about these type of ceramic capcitors, I found this out the hard way, luckly I saved the originals and put them back in, wow! what a difference between the two types, wish I could find somewhere I could get some of these type capacitors, any ideas?
:::Mark
:::Hi Greg
: Thanks for the info, now at least i know of a suitable replacement type if I ever need them.
:Mark

:~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:
:Foul…Foul…it seems that the description and limited dimensional and shape info that you gave was in the order of the blind man’s description of the different aspects of an elephant from his perspective.. I was thinking of more “turns” being all across the caps body…but fortunately Thomas hit it right , in the respect of there only being 1-1/2 turns of wire to bond with the end caps being soldered on..
:I just realized after that final supplication of the model and equipment that you are still on that Zenith that you learned about the futility in messing with the IF strip that was even initially in a proper operational state.
:The same would hold true for the tuner and all of its caps. The most work typically needed on a tuner is a cleaning of contact wafers or strips of any oxide or debris and a thin coating of them with an anti oxidant . Then a peek inside at tubes plate and screen resistors for scorching in case there has been a shorted tuner tube present in the sets history. Be sure that prescribed tube shields are in place. That’s it.
:Herewith is a zoom up of the units tuner…..within the realm of the threshold whereupon pixelation starts to inhibit definition.
:
:http://img111.imageshack.us/img111/4375/zenithbwtnr7lz.jpg
:
:Three tubular ceramic caps are viewable as a pair at C6,7 and the best view of one is C8. all of these were of what I called the ugly ones with their like conformal coatings . The smaller prettier ones would be the critical ones in the osc ckt as C17,18. Typically painted white with their color dots or slashes for color coding upon the cases, Or the very prettiest ones were some that retained their cases shiny silvering with the color codes laid on top of them.. I certainly hope that you have not touched them as they have special characteristics and anyway, are as fault free as a cap can be.
:If a sets tuner/and/or/I.F. stage has experienced multiple random “experimental adjustments” ( that’s a definite downhill creating situation) the only way to obtain optimum performance again is to have a sweep and marker generator and be well versed on how to actually perform a sweep alignment. In the end one is to the point of micro adjustments of inductive and capacitive values , with each interacting with each other until a final proper response curve along with proper stage gain is attained.
:P.S. C10 and C7 were red designated just to point out them as being ceramic piston variable caps.
:73’s de Edd
:
:
:
:~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:::Mark, I have replaced them with silver mica caps and they work just fine.
:::Greg
:::
:::::I think I know what you're talking about. You're talking about tubular ceramic condensers. These are made by putting a thin metal film or foil on the inside and outside of a ceramic tube. Each "electrode" or "plate" sticks out one end of the tube and has a few turns of wire wound around it and soldered to it. These look similar to some "dog bone" style resistors. Color dots are usually used for coding. The color dot systems can be found here on the internet. These condensers are extremely reliable. Sometimes they are encased in a brown material, perhaps an epoxy of sorts, or some clay-like material.
:::::
:::::Thomas
::::Hi Thomas
:::: Yep, thats exactly what they look like, now I know what they are, and I can tell you this also, NPO Ceramics will not work in place of them, so there must be something very special about these type of ceramic capcitors, I found this out the hard way, luckly I saved the originals and put them back in, wow! what a difference between the two types, wish I could find somewhere I could get some of these type capacitors, any ideas?
::::Mark
::::Hi Greg
:: Thanks for the info, now at least i know of a suitable replacement type if I ever need them.
::Mark
Hi Edd
I was merely just curious as too what type of capacitor they were, so as too any future situations I could find a suitable replacement, if I came across a bad one, as far as the set goes, its working great! I even have cable tv hooked up too it, of course through a cable ready VCR, I did find however there were a couple more tubes I had too replace, one of which was the sound detector, it was weak and would give me raspy audio when first turned on, after the tube reached its best operating condition it was ok, wow! what a difference with a new good sound detector tube, its instantly clean clear sound along with a great picture! this unit is really something! it absolutly has too be my most prized piece!
Mark