Hello All,
I just restored (replaced all the paper and filter capacitors and lots of wires with cracked insulation) this radio, however I am having trouble with the plates of the tuning capacitor. I cannot see where they're touching ("shorted"). They are touching all through the band except for the very highest frequencies. It sounds like static when I tune. There are some breaks in the static but not enough to tune in anything. Should I get some thin strips of plastic and try to slide them in between the plates? It seems to be in the third section. That's where the resistance gets lower as I tune. This has very few plates in it. The other sections' resistance doesn't seem to change. So that's my guess as to where the problem is.
This is an unusual tuning capacior for an AC/DC chassis. Usually there are only two sections.

Thanks,

Dave

You have a wonderful Zenith with a tuned RF pre-amplifier. Not often you see 3 stages in an AC-DC...true.

Regarding plastic, be careful with what you use, as this might bend the plates (while the plastic is inserted...not necessarily permanently), causing shorts elsewhere....you might never end your search. If you remove the condenser and pass bright light through it, you should probably be able to see where the plates touch. Otherwise send it to someone you know who might be better at seeing the short.

T.

Thomas,
It's a great radio. However someone "fixed" it years ago so that it would sound broken. They had one capacitor connected from the output of the pre-amp to positive and another from that same point to power supply negative. I guess whoever did that wanted to sell the original owner a new radio. I had to remove both of those capacitors completely.
I am going to have to bring the radio to someone I know who can correct the capacitor problem. This capacitor has no adjustment screw. But I think it can be adjusted somehow.

Dave
:You have a wonderful Zenith with a tuned RF pre-amplifier. Not often you see 3 stages in an AC-DC...true.
:
:Regarding plastic, be careful with what you use, as this might bend the plates (while the plastic is inserted...not necessarily permanently), causing shorts elsewhere....you might never end your search. If you remove the condenser and pass bright light through it, you should probably be able to see where the plates touch. Otherwise send it to someone you know who might be better at seeing the short.
:
:T.

:Hello All,
: I just restored (replaced all the paper and filter capacitors and lots of wires with cracked insulation) this radio, however I am having trouble with the plates of the tuning capacitor. I cannot see where they're touching ("shorted"). They are touching all through the band except for the very highest frequencies. It sounds like static when I tune. There are some breaks in the static but not enough to tune in anything. Should I get some thin strips of plastic and try to slide them in between the plates? It seems to be in the third section. That's where the resistance gets lower as I tune. This has very few plates in it. The other sections' resistance doesn't seem to change. So that's my guess as to where the problem is.
: This is an unusual tuning capacior for an AC/DC chassis. Usually there are only two sections.
:
:Thanks,
:
:Dave

Adjusting the pre-load screw at the rear of the center shaft on my Zenith fixed an identical problem. Its' static problem was at the low end of the band. Loosen the lock nut and then make a very small adjustment of the screw. Also make sure that the grounding wiper is making good contact with the center shaft.

Will

Will,
I have searched the capacitor and can find no such lock nut or screw. The end of shaft is into solid metal. Is it on the knob end? I'll look.

Thanks,

Dave
::Hello All,
:: I just restored (replaced all the paper and filter capacitors and lots of wires with cracked insulation) this radio, however I am having trouble with the plates of the tuning capacitor. I cannot see where they're touching ("shorted"). They are touching all through the band except for the very highest frequencies. It sounds like static when I tune. There are some breaks in the static but not enough to tune in anything. Should I get some thin strips of plastic and try to slide them in between the plates? It seems to be in the third section. That's where the resistance gets lower as I tune. This has very few plates in it. The other sections' resistance doesn't seem to change. So that's my guess as to where the problem is.
:: This is an unusual tuning capacior for an AC/DC chassis. Usually there are only two sections.
::
::Thanks,
::
::Dave
:
:
:Adjusting the pre-load screw at the rear of the center shaft on my Zenith fixed an identical problem. Its' static problem was at the low end of the band. Loosen the lock nut and then make a very small adjustment of the screw. Also make sure that the grounding wiper is making good contact with the center shaft.
:
:Will

Usually it is on the butt end (non-shaft end), but many condensers were manufactured without such a nut. Bending the frame makes the adjustment. I strongly recommend that you DO NOT bend the frame until after thoroughly examining the condenser. Unless the radio was severely damaged to the extent that the condenser would have been struck, it probably is in alignment. Unless there is evidence that all blades are shifted one way or another, the frame is probably in alignment. Take the condenser out and hold it to a very bright light (so that the light shines through).

T.

Thomas,
Yes all the plates are shifted. None are centered.
So the person who does metal work should be able to adjust it.

Thanks,

Dave
:Usually it is on the butt end (non-shaft end), but many condensers were manufactured without such a nut. Bending the frame makes the adjustment. I strongly recommend that you DO NOT bend the frame until after thoroughly examining the condenser. Unless the radio was severely damaged to the extent that the condenser would have been struck, it probably is in alignment. Unless there is evidence that all blades are shifted one way or another, the frame is probably in alignment. Take the condenser out and hold it to a very bright light (so that the light shines through).
:
:T.

After you have confirmed that the situation that Sir Will described, was not the case (not having a positive grounding of the capacitors rotor shaft to the infrastructure frame through the multiple used tensioned U contactors or its intermittancy). Nor that it is not a masive shift of all of the interspacings en masse.... as per Thomas thought.And if that is true....and I have no visual on the suspect unit....considering the front to back end play on the rotor unit to be rock solid... is there any leeway on a repositoning of the stator section(s)?

Just for run of the mill plate scrapings:

Parte Un:
And..... my positive corrective procedure for that requires the whole cap to be pulled in order to get optimal access to all positions of the uinit as well as to not cross contaminate the chassis proper.

Initially use a small artist hog bristle brush repetetively wetted in paint thinner /or/ denatured alcohol /or/ acetone /or/ MEK to clean the exposed U contacts and adjunct rotor contact area to clean away all old lubricant / sludge.

The procedure is then to get some of the automobile valve grinding compound that comes in the little green double-sided container with its opposed captive press in lids. The container halves will contain coarse and fine grinding compunds within each half..... we are only interested in the FINE portion. Put a small "dollop" into the top of the pulled lid and thin it down to fingernail polish consistancy / viscosity with paint thinner. The corective procedure is two part, initially cut several small 1/4 wide by 3 in long strips of Kraft paper from a paper bag. Then you dip the end of one strip into the "pookie" such that both sides are wetted . Next you select the first U connector to be to serviced and use a small jewelers screwdriver /small gauge wire / etc. to oppose one half of the U connectors ever so slightly away from the contact area of the rotor shaft that it is engaged into. That should be only enough to let the loaded paper just slide into place betwen the contacting surfaces (you don't want to spring it any and end up decreasing its tension) and then you can move the strip back and forth laterally to enact some frictional cleaning of the now re- mated surfaces...thereby immaculately cleaning their contacting areas.The you work on down the remaining contact areas using the same procedure.
An alternate procedure is to dip a fine sable artists brush into the solution and ever so slightly "paint" a small strip of the semicircle contacting area of the capacitor rotor in the contact area that is to be cleaned and then do MULTIPLE semi rotations of the rotor to
engage cleaning actions between the two contacting areas of the concerned tandem contact pairs. The last "painting" may be required multiple times, as the "pookie" tends to get shifted aside by the rotational action. Whereas, when using the porous paper, it tends to acquire a fresh particulate charging, since it is interdispersed all within the papers pores.
The net end result is one immaculate cleaning of the contact areas without the chance of degrading contact tensioning.

The final step, of course, being to clean away foreign material used in the cleaning process. That can be done by combinationals of comperssed air purges, brush on solvents, pressurized cleaners/degreasers, or as simple as a solvent inside a polyethylene "mustard/ ketchup" dispenser with a mere pinhole sized aperature within its end (#).
(#) If the stock devices hole is too large...fuse it over with a hot soldering iron and use a pin to reform to a smaller size) , such that a pressurized stream expulsion of cleaner can be produced by firm hand pressure upon its sides.

Re lube the rotors roller bearings and end ball bearing. BUT, for the contact areas, I like to use clear Dow Corning Z-5 sliicone grease or go to a premium hardware and get some of GUNK's branded Plumbers Silicone Grease in its small poly cannister. It will provide a long time (4 eons) connector integrity of the rotors contact surfaces, as it will not heat sag and drift down and off / away from its surfaces from internally created tube heat , as happens with petroleum based products. As well, its inert nature keeps the contact surfaces in pristine unoxidized condition , which is way more that I could say with the use of petro-based product and its potential introduction of any acidic or sulfur based contamination.

Parte Deux:
Is for finding those minute and elusive rotational intercontactings of air tuning capacitors rotor to stator plate sets.For those touchy conditions where an ohmmeter test just can't decisively differentiate it....or where you alternate between two plates touching and one free to then having two free and one touching and then three touching...etc.etc.

Aside......Putting the situation it into the words of the old Masters:
" Holy Mackeral 'dere Andy, now lets see here what's done dis com-bob-ulated with 'dis here radio's tuning CON-dense-erator.
Now listen here Amos, if'n you will holds 'dat wire 'dere and I will hold 'dis wire here ... we gonna done see who exactly is being
the "contact-or" and who be the "contact-ee"

This is supplemental to the above condition in Parte Un....but if the caps rotor contact area is in good condition, it may be utilized solely for the pinpointing of shorts.

The particular section involved with the problem potentially has been zeroed in on already....e.g. the RF-Mixer-Osc section.
This troubleshooting technique incvolves the removal of the particular stator terminals wiring connection to the radio chassis circuitry that will then then permit the connection of a power source across the free stator's wiring terminal and the rotors contact to the capacitor frame. The idea is to apply adequate power across the pair and then slowly run the stator through its rotational range and view down from the topside of the capacitor while gradually intermeshing plates see if any sparking is detected between adjacent touching plates at any time in their rotation.
This can be with different degrees of shortings of different or multiple plates, as typically, they occur at different degrees of the rotational axis of the rotor. For the worst cases, I typically connect an incandescant lamp in series with a bench power supply line (6-12 VDC) so that initially, you can have an indication of when a short initially occurs, by the lamp flashing on. Then you can use two methods. The first is to come to the point of rotor rotation where the short is just initiated, and use a toothpick moved in from the side to sequentially gently nudge rotor plates aside until the short clears and then make corrective plate skewing for corrective repositioning and then enact a reswinging of the capacitor thru its arc to see if shorting recurs or if other plates are coincidentally at fault.
The last method for worst case procedure is for those cases of very minute touchings of plates. This requires that the system be performed in a pitch dark situaton such that ones primary observational light source is to be a hand held battery penlight. Initially the rotor is moved to the area where the short is occuring and then the penlight is switched off and that incandescant lamp covered up with a blackout cloth. One then micro-rotates the rotor while observing for minute sparks occuring at the plate contact area, flipping on the penlight then permits zeroing in on the guilty pair with micro-reorientation of the suspect plates and retest.

73's de Edd.

Edd,
The person I brought it to poured some thinned nail polish onto the plates so that they can no longer touch and the tuning capacitor works fine.
I had tried all the other suggestions but the plates were touching it too many places to find them. I didn't want to bend the frame either.
Thanks for everyone's help.
Dave
:After you have confirmed that the situation that Sir Will described, was not the case (not having a positive grounding of the capacitors rotor shaft to the infrastructure frame through the multiple used tensioned U contactors or its intermittancy). Nor that it is not a masive shift of all of the interspacings en masse.... as per Thomas thought.And if that is true....and I have no visual on the suspect unit....considering the front to back end play on the rotor unit to be rock solid... is there any leeway on a repositoning of the stator section(s)?
:
:
:Just for run of the mill plate scrapings:
:
:Parte Un:
:And..... my positive corrective procedure for that requires the whole cap to be pulled in order to get optimal access to all positions of the uinit as well as to not cross contaminate the chassis proper.
:
:Initially use a small artist hog bristle brush repetetively wetted in paint thinner /or/ denatured alcohol /or/ acetone /or/ MEK to clean the exposed U contacts and adjunct rotor contact area to clean away all old lubricant / sludge.
:
:The procedure is then to get some of the automobile valve grinding compound that comes in the little green double-sided container with its opposed captive press in lids. The container halves will contain coarse and fine grinding compunds within each half..... we are only interested in the FINE portion. Put a small "dollop" into the top of the pulled lid and thin it down to fingernail polish consistancy / viscosity with paint thinner. The corective procedure is two part, initially cut several small 1/4 wide by 3 in long strips of Kraft paper from a paper bag. Then you dip the end of one strip into the "pookie" such that both sides are wetted . Next you select the first U connector to be to serviced and use a small jewelers screwdriver /small gauge wire / etc. to oppose one half of the U connectors ever so slightly away from the contact area of the rotor shaft that it is engaged into. That should be only enough to let the loaded paper just slide into place betwen the contacting surfaces (you don't want to spring it any and end up decreasing its tension) and then you can move the strip back and forth laterally to enact some frictional cleaning of the now re- mated surfaces...thereby immaculately cleaning their contacting areas.The you work on down the remaining contact areas using the same procedure.
: An alternate procedure is to dip a fine sable artists brush into the solution and ever so slightly "paint" a small strip of the semicircle contacting area of the capacitor rotor in the contact area that is to be cleaned and then do MULTIPLE semi rotations of the rotor to
:engage cleaning actions between the two contacting areas of the concerned tandem contact pairs. The last "painting" may be required multiple times, as the "pookie" tends to get shifted aside by the rotational action. Whereas, when using the porous paper, it tends to acquire a fresh particulate charging, since it is interdispersed all within the papers pores.
:The net end result is one immaculate cleaning of the contact areas without the chance of degrading contact tensioning.
:
:The final step, of course, being to clean away foreign material used in the cleaning process. That can be done by combinationals of comperssed air purges, brush on solvents, pressurized cleaners/degreasers, or as simple as a solvent inside a polyethylene "mustard/ ketchup" dispenser with a mere pinhole sized aperature within its end (#).
:(#) If the stock devices hole is too large...fuse it over with a hot soldering iron and use a pin to reform to a smaller size) , such that a pressurized stream expulsion of cleaner can be produced by firm hand pressure upon its sides.
:
:Re lube the rotors roller bearings and end ball bearing. BUT, for the contact areas, I like to use clear Dow Corning Z-5 sliicone grease or go to a premium hardware and get some of GUNK's branded Plumbers Silicone Grease in its small poly cannister. It will provide a long time (4 eons) connector integrity of the rotors contact surfaces, as it will not heat sag and drift down and off / away from its surfaces from internally created tube heat , as happens with petroleum based products. As well, its inert nature keeps the contact surfaces in pristine unoxidized condition , which is way more that I could say with the use of petro-based product and its potential introduction of any acidic or sulfur based contamination.
:
:Parte Deux:
:Is for finding those minute and elusive rotational intercontactings of air tuning capacitors rotor to stator plate sets.For those touchy conditions where an ohmmeter test just can't decisively differentiate it....or where you alternate between two plates touching and one free to then having two free and one touching and then three touching...etc.etc.
:
:Aside......Putting the situation it into the words of the old Masters:
:" Holy Mackeral 'dere Andy, now lets see here what's done dis com-bob-ulated with 'dis here radio's tuning CON-dense-erator.
:Now listen here Amos, if'n you will holds 'dat wire 'dere and I will hold 'dis wire here ... we gonna done see who exactly is being
:the "contact-or" and who be the "contact-ee"
:
:This is supplemental to the above condition in Parte Un....but if the caps rotor contact area is in good condition, it may be utilized solely for the pinpointing of shorts.
:
:The particular section involved with the problem potentially has been zeroed in on already....e.g. the RF-Mixer-Osc section.
:This troubleshooting technique incvolves the removal of the particular stator terminals wiring connection to the radio chassis circuitry that will then then permit the connection of a power source across the free stator's wiring terminal and the rotors contact to the capacitor frame. The idea is to apply adequate power across the pair and then slowly run the stator through its rotational range and view down from the topside of the capacitor while gradually intermeshing plates see if any sparking is detected between adjacent touching plates at any time in their rotation.
:This can be with different degrees of shortings of different or multiple plates, as typically, they occur at different degrees of the rotational axis of the rotor. For the worst cases, I typically connect an incandescant lamp in series with a bench power supply line (6-12 VDC) so that initially, you can have an indication of when a short initially occurs, by the lamp flashing on. Then you can use two methods. The first is to come to the point of rotor rotation where the short is just initiated, and use a toothpick moved in from the side to sequentially gently nudge rotor plates aside until the short clears and then make corrective plate skewing for corrective repositioning and then enact a reswinging of the capacitor thru its arc to see if shorting recurs or if other plates are coincidentally at fault.
:The last method for worst case procedure is for those cases of very minute touchings of plates. This requires that the system be performed in a pitch dark situaton such that ones primary observational light source is to be a hand held battery penlight. Initially the rotor is moved to the area where the short is occuring and then the penlight is switched off and that incandescant lamp covered up with a blackout cloth. One then micro-rotates the rotor while observing for minute sparks occuring at the plate contact area, flipping on the penlight then permits zeroing in on the guilty pair with micro-reorientation of the suspect plates and retest.
:
:73's de Edd.

Been using the lethal voltage method. Wear rubber gloves.

1) Remove the ganged tuning cap.

2) Connect AC power to tuning section with a 60 watt lamp in series.

3) Lamp come on and limits current which burns out any oxidation between plates. Expect to see some sparks. Bend plates and make endplay adjustments as needed.

Richard

:Been using the lethal voltage method. Wear rubber gloves.
:
:1) Remove the ganged tuning cap.
:
:2) Connect AC power to tuning section with a 60 watt lamp in series.
:
:3) Lamp come on and limits current which burns out any oxidation between plates. Expect to see some sparks. Bend plates and make endplay adjustments as needed.
:
:Richard

Where are you guys going??
A single small sheet of kitchen wax paper inserted between the suspect plates, or all of them during normal operation, will isolate the problem.

marv

::Been using the lethal voltage method. Wear rubber gloves.
::
::1) Remove the ganged tuning cap.
::
::2) Connect AC power to tuning section with a 60 watt lamp in series.
::
::3) Lamp come on and limits current which burns out any oxidation between plates. Expect to see some sparks. Bend plates and make endplay adjustments as needed.
::
::Richard

Wax paper is an excellent idea! Also, if only one section seems to be totally out of alignment (all plates are touching, not just one, and it doesn't seem like they're bent), you can move the stator instead of the rotor. It takes patience, thought, and care. If you don't think that you can do it, don't. The stators can usually be shifted just slightly, though, by moving the solid metal ends with a screw driver blade (prying). Shift the end that needs aligning.
If it seems, though, that the plates are only touching on their outer edges, but are centered near the centers, then the rotor plates are probably just bent over...not out of alignment. ....Things are out of alignment when the plates touch evenly from the inner-most diameter to the outer-most, or when it appears that the stator has shifted on one side or both. Sorry for such vague wording. I can't come up with proper descriptions right now. If I could actually show you what I mean on the condenser, it'd all make sense.

T.

First ... locate or isolate the problem.

I have used the ohm meter with an audible indicator to "hear" the shorts.

Sometimes it can be corrected with a properly mounted frame.
I recently had a radio that didn't seem to have any shorting in the condenser until after I removed and washed and replaced it. Then the plates seemed to be touching all over the place.... WHY I thought... what changed??
I KNOW I didn't disturb them during washing... so it was time to THINK....AHAH!!! I found it. When I remounted it I properly did tighten down all the mounting hardware on the front and rear of the frame. But there was the rub!!
no pun intended
Tightening the frame down was twisting it just enough to cause the problem. When I backed off the screws in the rear mount ...the frame straightened and all the shorts disappeared.!!... then I vaguely remembered that when I removed those screws they wern't too tight in the first place...see?

I have also patiently fixed touching plates by carefully realigning them one by one with an EXACTO like razor blade knife that allows for the blade to be extended way out. I slide it in the touching plate areas and gently pry them to the side a bit till clear.. carefully. not to difficult but not so easy either.

On seriously oxidized or cruddy plates I have simply opened or rotated them open to minimum capacitance. Then I use an emory board to slide between the plates and sand away. If that's to fat I'll use emory cloth.. single or folded over double. There is a new kind of double sided mesh-like emory cloth on a long roll... in the plumbing section at the trusty hardware store.

Patience..Perseverence and common sense... is the rule.

:First ... locate or isolate the problem.
:
:I have used the ohm meter with an audible indicator to "hear" the shorts.
:
:Sometimes it can be corrected with a properly mounted frame.
:I recently had a radio that didn't seem to have any shorting in the condenser until after I removed and washed and replaced it. Then the plates seemed to be touching all over the place.... WHY I thought... what changed??
:I KNOW I didn't disturb them during washing... so it was time to THINK....AHAH!!! I found it. When I remounted it I properly did tighten down all the mounting hardware on the front and rear of the frame. But there was the rub!!
:no pun intended
: Tightening the frame down was twisting it just enough to cause the problem. When I backed off the screws in the rear mount ...the frame straightened and all the shorts disappeared.!!... then I vaguely remembered that when I removed those screws they wern't too tight in the first place...see?
:
:I have also patiently fixed touching plates by carefully realigning them one by one with an EXACTO like razor blade knife that allows for the blade to be extended way out. I slide it in the touching plate areas and gently pry them to the side a bit till clear.. carefully. not to difficult but not so easy either.
:
:On seriously oxidized or cruddy plates I have simply opened or rotated them open to minimum capacitance. Then I use an emory board to slide between the plates and sand away. If that's to fat I'll use emory cloth.. single or folded over double. There is a new kind of double sided mesh-like emory cloth on a long roll... in the plumbing section at the trusty hardware store.
:
:Patience..Perseverence and common sense... is the rule.
:
:BY THE WAY...OOOPs
:The other day I mentioned to Mark that he typed "too" when he meant "to".... and I reminded him that it is hard to understand sometimes while reading...and now I just noticed that "I" did the exact opposite thing... I accidently typed "to" instead of "too" in severl locations.... what a dunce I am.
.. if there is a spelling God out there...may he please forgive both my impertinence as well as my typos.. lol

Peter,
There were so many shorts the problem was solved by pouring thinned nail polish on the plates to insulate them. Now the tuning capacitor works fine.

Thanks,

Dave
::First ... locate or isolate the problem.
::
::I have used the ohm meter with an audible indicator to "hear" the shorts.
::
::Sometimes it can be corrected with a properly mounted frame.
::I recently had a radio that didn't seem to have any shorting in the condenser until after I removed and washed and replaced it. Then the plates seemed to be touching all over the place.... WHY I thought... what changed??
::I KNOW I didn't disturb them during washing... so it was time to THINK....AHAH!!! I found it. When I remounted it I properly did tighten down all the mounting hardware on the front and rear of the frame. But there was the rub!!
::no pun intended
:: Tightening the frame down was twisting it just enough to cause the problem. When I backed off the screws in the rear mount ...the frame straightened and all the shorts disappeared.!!... then I vaguely remembered that when I removed those screws they wern't too tight in the first place...see?
::
::I have also patiently fixed touching plates by carefully realigning them one by one with an EXACTO like razor blade knife that allows for the blade to be extended way out. I slide it in the touching plate areas and gently pry them to the side a bit till clear.. carefully. not to difficult but not so easy either.
::
::On seriously oxidized or cruddy plates I have simply opened or rotated them open to minimum capacitance. Then I use an emory board to slide between the plates and sand away. If that's to fat I'll use emory cloth.. single or folded over double. There is a new kind of double sided mesh-like emory cloth on a long roll... in the plumbing section at the trusty hardware store.
::
::Patience..Perseverence and common sense... is the rule.
::
::BY THE WAY...OOOPs
::The other day I mentioned to Mark that he typed "too" when he meant "to".... and I reminded him that it is hard to understand sometimes while reading...and now I just noticed that "I" did the exact opposite thing... I accidently typed "to" instead of "too" in severl locations.... what a dunce I am.
:.. if there is a spelling God out there...may he please forgive both my impertinence as well as my typos.. lol

That's a clever idea... I wonder if spraying it with anything like lacquer or krylon or
....egads!... even paint would work?

Peter,
He had to pour the thinned nail polish carefully. I think it was when they were unmeshed. But he let it dry before turning it again. I wasn't there. So I'm not exactly sure how he put the nail polish on.

Dave
:That's a clever idea... I wonder if spraying it with anything like lacquer or krylon or
: ....egads!... even paint would work?

Thats great to isolate the problem, but how long will a thin coating of nail polish last. Ask the ladies how soon it peels off. Maybe forever if it doesn't get tuned, which doesn't solve the original problem of inter-meshing capacitor plates touching. The stator (the rotating member) has obviously shifted its position, and the first order of business is to determine why, then resolve the repair issue. Can't really be that difficult, if one is willing to paint nail polish on all the plates (both sides I assume)wait for it to dry, "divine" the problem solved vs slipping a sheet of wax paper between them, then I assume problem solving is a secondary issue.

marv

:That's a clever idea... I wonder if spraying it with anything like lacquer or krylon or
: ....egads!... even paint would work?

Well Dave what do you think? Had you really given up finding it.. and felt this was the last ditch effort already?
...cause I really agree with Marv here.. because, y'know I was kinda wondering how long it might last too.. but then I just thought that if you got that idea from another respected source then maybe it has been proven to be worthy..
.. though for me personally... unless I KNEW that that was the fastest and most soundly permanent method.. I too would opt for solving it by actually locating the problem and eliminating it ....as I described in my earlier post... can't be that difficult.. you're right.

Well, you could always send the capacitor to me, and I could fix it for you.

T.

Y'know Thomas.. since you love this so much and are so good at it..that may be a great idea for you to make some extra money and enjoy your work too.
You could advertize localy and/or on the net and do this as a part-time business.
Indalicio from Brazil does just that... full time.. and I think his radios come shipped to him from all over. His rent is much lower something like $250-$300 a month but he does one radio each month to pay his rent..

Guess I could. I'm not an expert, though, and sometimes I worry that someone will send me something that I just can't fix, which would be a waste of their time and money. For instance, a guy on here sent me a radio that was very irratic in performance, and just wouldn't tune properly. It lacked sensitivity and everything. I got it to really perform well after finding a misconnected wire, and after really tuning it up and cleaning some things that I suspected, but it still had very slight problems. I could get it to be selective down to 5 KC or less, and every station across the dial would hit the mark perfectly. Then, on some days, the stations would shift, and the sensitivity would go down. We suspected shorted IF transformers, as this was all that was left, but I have no way of testing shorted transformers. I guess one could build an oscillator with a radiating coil, which had an AC milliammeter wired to it. Then, by holding the coil close to the IF transfomer, a short could be sensed by the current draw. I really don't know how to do this, though, and currently lack the time to figure it out. I guess that this problem isn't a regular one, at least in my experience, and with enough semi-regular repair jobs, I could earn enough money to have the time to investigate things like this. I just don't see tons of people shipping radios to me, though. Maybe so....maybe it could work. There are enough people in the world that I guess the odds are good.

T.

Well the guy in Brazil sure gets a steady supply...

as fer as IFs go... you can keep a few if transformers around and substitur them for a while to see ifthe problem goes away.. things like that..
.. oh and the guy in brazil... has a coil re-winder and re-winds IFs.. he's doing that Zenith 6d-525 for me that caught fire... doing the whole radio including chroming the chassis and refinishing the wood .. for $130 !
.. or at least that's the price if I ever get it back lol... he's been doing it spae time for months now...

Thomas,
Go for it!! Got nothing to loose but time. The Thomas fix you noted for if transformers is called a Grid Dip Oscillator. At the point of resonance, the coil under test consumes RF energy, causing the GDO meter to dip. I'm sure you have heard of those.

marv

:Guess I could. I'm not an expert, though, and sometimes I worry that someone will send me something that I just can't fix, which would be a waste of their time and money. For instance, a guy on here sent me a radio that was very irratic in performance, and just wouldn't tune properly. It lacked sensitivity and everything. I got it to really perform well after finding a misconnected wire, and after really tuning it up and cleaning some things that I suspected, but it still had very slight problems. I could get it to be selective down to 5 KC or less, and every station across the dial would hit the mark perfectly. Then, on some days, the stations would shift, and the sensitivity would go down. We suspected shorted IF transformers, as this was all that was left, but I have no way of testing shorted transformers. I guess one could build an oscillator with a radiating coil, which had an AC milliammeter wired to it. Then, by holding the coil close to the IF transfomer, a short could be sensed by the current draw. I really don't know how to do this, though, and currently lack the time to figure it out. I guess that this problem isn't a regular one, at least in my experience, and with enough semi-regular repair jobs, I could earn enough money to have the time to investigate things like this. I just don't see tons of people shipping radios to me, though. Maybe so....maybe it could work. There are enough people in the world that I guess the odds are good.
:
:T.

Yes Thomas.. also called a grid dip meter..
I'm sure there are plans on how to build one in your new (1946) handy-dandy ARRL ham manual...

Yep, never gave them much thought, though. Guess I should look into them.

T.