The RCA 56x10 (1945 vintage)
http://www.nostalgiaair.org/PagesByModel/992/M0014992.pdf
...that I just finished completely re-doing last week and now up for sale on Ebay... is exhibiting a new interesting symptom tonight.

I was listening to it all night nicely... then a few minuets ago it just started to make loud static burts like lighting storm noises... almost obliterating the audio.

At first I thought it was external but then it wouldn't stop.

TW..( This radio has the older, conventional looking, IF cans so I don't really think they have the dangerous integrated silver mica caps in there)

So anyway..
Then I figured... since every capacitor in the radio is new... what else can it be?
... maybe an inter-elctrode shorting problem in one of the RF tubes?
So I tapped them with a brush handle a bit and when it stopped I thought that was it.
.. but a few minuets later as I tuned down the dial and as soon as I got to the strongest station it started again.
So I tried pulling the RF tubes and replacing them right on down the line till every tube in the set was changed and the static is still there.

Now...Here's the real big clue....that I haven't figured out yet...lol

... I noticed that as I tune across the dial it is silent until I hit a station/signal then there's loud static... but totally quiet between stations!!

Now this is a strange one. My first thought is that it has something to do with the AVC circuit.

But I can't see how a faulty AVC cap would cause static like this.

I think that C-14 is the AVC capacitor.
.. the print shows it as a .035uf ...( kinda weird value and also weird because I usually see .05uf)
... anyway I had replaced the .035 uf with a .04uf which is the closest I had.

So unless there is a cold solder joint or a new component quit... I have no idea for sure where to start.
It's now about 7:30 am and I was already up all night as usual anyway and was just about ready for bed.
.. but I'm so curious now I kinda want to start poking around in there now.
So maybe I will. Or M A Y B E... I might just hit the sack too.
But in the mean time.. any ideas will be apreciated... and if I do get it solved I'll certainly post it later.

Well it's a few hours later and no luck.
I found it DOES make static between stations too just lower level.

If I short across the AVC cap ofcourse the volume drops way down but the static goes away clean. I have to turn vol way up to hear on strongest stations but there is NO static. As soon as I take the short off it's like a thunderstorm.

It really does sound so much like that dreaded silver mica disease type noise.
But these IF's use separate variable caps o each side.
So I looked to see where B+ might be sneaking into a grid someplace.
The first place I looked at was C3 the coupling cap from the RF stage plate to the 1st det/oec grid. So I changed it and same thing.

I've replaced almost everything. The mica caps ... even the new electrolytics in the power supply. The audio coupling caps too.
I even swapped out the entire first IF can for a spae I have... nothing makes it go away.
Sometimes it will get quiet and I think its gone but it starts agin in 30 seconds.. the volume or signal seems to get stronger when the static is loudest.

Remember... all tubes have been changed and I'm now running on the changed tubes.

I've also changed c14 the AVC cap... and C9 and C15 and C4
I even temporarily replaced the padder C30 with a 500pf fixed cap....No dice.

Same random..loud bursty staticy crashing noise.

I am fresh out of ideas... going to catch some zzzz s

:Well it's a few hours later and no luck.
:I found it DOES make static between stations too just lower level.
:
:If I short across the AVC cap ofcourse the volume drops way down but the static goes away clean. I have to turn vol way up to hear on strongest stations but there is NO static. As soon as I take the short off it's like a thunderstorm.
:
:It really does sound so much like that dreaded silver mica disease type noise.
:But these IF's use separate variable caps o each side.
:So I looked to see where B+ might be sneaking into a grid someplace.
:The first place I looked at was C3 the coupling cap from the RF stage plate to the 1st det/oec grid. So I changed it and same thing.
:
:I've replaced almost everything. The mica caps ... even the new electrolytics in the power supply. The audio coupling caps too.
:I even swapped out the entire first IF can for a spae I have... nothing makes it go away.
:Sometimes it will get quiet and I think its gone but it starts agin in 30 seconds.. the volume or signal seems to get stronger when the static is loudest.
:
:Remember... all tubes have been changed and I'm now running on the changed tubes.
:
:I've also changed c14 the AVC cap... and C9 and C15 and C4
:I even temporarily replaced the padder C30 with a 500pf fixed cap....No dice.
:
:Same random..loud bursty staticy crashing noise.
:
:I am fresh out of ideas... going to catch some zzzz s

Have you tried the old trick using a hair dryer to heat components or the freeze mist to cool them? Might even find a bad solder joint if you're lucky.

:Well it's a few hours later and no luck.
:I found it DOES make static between stations too just lower level.
:
:If I short across the AVC cap ofcourse the volume drops way down but the static goes away clean. I have to turn vol way up to hear on strongest stations but there is NO static. As soon as I take the short off it's like a thunderstorm.
:
:It really does sound so much like that dreaded silver mica disease type noise.
:But these IF's use separate variable caps o each side.
:So I looked to see where B+ might be sneaking into a grid someplace.
:The first place I looked at was C3 the coupling cap from the RF stage plate to the 1st det/oec grid. So I changed it and same thing.
:
:I've replaced almost everything. The mica caps ... even the new electrolytics in the power supply. The audio coupling caps too.
:I even swapped out the entire first IF can for a spae I have... nothing makes it go away.
:Sometimes it will get quiet and I think its gone but it starts agin in 30 seconds.. the volume or signal seems to get stronger when the static is loudest.
:
:Remember... all tubes have been changed and I'm now running on the changed tubes.
:
:I've also changed c14 the AVC cap... and C9 and C15 and C4
:I even temporarily replaced the padder C30 with a 500pf fixed cap....No dice.
:
:Same random..loud bursty staticy crashing noise.
:
:I am fresh out of ideas... going to catch some zzzz s
:
:
:
:
Hi Peter,
Could the kind of capacitor be an issue in the AVC section? I am wondering that since shorting removes the noise, perhaps a larger capacitor in the AVC may give an even better clue to the problem.

Best Regards,

Bill

:Well it's a few hours later and no luck.
:I found it DOES make static between stations too just lower level.
:
:If I short across the AVC cap ofcourse the volume drops way down but the static goes away clean. I have to turn vol way up to hear on strongest stations but there is NO static. As soon as I take the short off it's like a thunderstorm.
:
:It really does sound so much like that dreaded silver mica disease type noise.
:But these IF's use separate variable caps o each side.
:So I looked to see where B+ might be sneaking into a grid someplace.
:The first place I looked at was C3 the coupling cap from the RF stage plate to the 1st det/oec grid. So I changed it and same thing.
:
:I've replaced almost everything. The mica caps ... even the new electrolytics in the power supply. The audio coupling caps too.
:I even swapped out the entire first IF can for a spae I have... nothing makes it go away.
:Sometimes it will get quiet and I think its gone but it starts agin in 30 seconds.. the volume or signal seems to get stronger when the static is loudest.
:
:Remember... all tubes have been changed and I'm now running on the changed tubes.
:
:I've also changed c14 the AVC cap... and C9 and C15 and C4
:I even temporarily replaced the padder C30 with a 500pf fixed cap....No dice.
:
:Same random..loud bursty staticy crashing noise.
:
:I am fresh out of ideas... going to catch some zzzz s
:
:
Peter,

Is it possible you may have a noisy resistor? R6,R5?

Radiodoc

:
:

Changed both those resistors.. no luck.
Also increase size of AVC cap tp .05uf... no luck
Replaced The 12sg7 again, also the 12sa7 det/osc... both from NOS... no luk..
Going to dinner... maybe try the 12sk7 1st If later.

:The RCA 56x10 (1945 vintage)
:http://www.nostalgiaair.org/PagesByModel/992/M0014992.pdf
: ...that I just finished completely re-doing last week and now up for sale on Ebay... is exhibiting a new interesting symptom tonight.
:
:I was listening to it all night nicely... then a few minuets ago it just started to make loud static burts like lighting storm noises... almost obliterating the audio.
:
:At first I thought it was external but then it wouldn't stop.
:
:TW..( This radio has the older, conventional looking, IF cans so I don't really think they have the dangerous integrated silver mica caps in there)
:
:So anyway..
:Then I figured... since every capacitor in the radio is new... what else can it be?
:... maybe an inter-elctrode shorting problem in one of the RF tubes?
: So I tapped them with a brush handle a bit and when it stopped I thought that was it.
:.. but a few minuets later as I tuned down the dial and as soon as I got to the strongest station it started again.
:So I tried pulling the RF tubes and replacing them right on down the line till every tube in the set was changed and the static is still there.
:
:Now...Here's the real big clue....that I haven't figured out yet...lol
:
:... I noticed that as I tune across the dial it is silent until I hit a station/signal then there's loud static... but totally quiet between stations!!
:
:Now this is a strange one. My first thought is that it has something to do with the AVC circuit.
:
:But I can't see how a faulty AVC cap would cause static like this.
:
:I think that C-14 is the AVC capacitor.
:.. the print shows it as a .035uf ...( kinda weird value and also weird because I usually see .05uf)
:... anyway I had replaced the .035 uf with a .04uf which is the closest I had.
:
:So unless there is a cold solder joint or a new component quit... I have no idea for sure where to start.
:It's now about 7:30 am and I was already up all night as usual anyway and was just about ready for bed.
:.. but I'm so curious now I kinda want to start poking around in there now.
:So maybe I will. Or M A Y B E... I might just hit the sack too.
:But in the mean time.. any ideas will be apreciated... and if I do get it solved I'll certainly post it later.
:
:
Hi Peter,
It was interesting reading. It seems you troubleshot it down to needing a good night's sleep.

All the Best,

Bill

Is the static possibly vibrating to the music? This might explain why you only get static when a station is tuned in. Could be a bad connection. Could be a bad component (cracked resistor or a condenser that is arcing over....hopefully you used high voltage condensers throughout). Could also be a partially shorting tube or a tube that is arcing internally. Perform an element to element shorts test and tap the tubes while you test them. You can also try tapping each tube while in the radio. Also make sure that the sockets are connecting properly, and that none of the tube pins have poor solder connections (wire vibrating around in the pin). It could also be an arcing output transformer, though I doubt this.

Thomas

Thoms...
It is staticy all the time and between stations just lower.. seems somehow related to the AVC.. but not sure.
if I pull off the AVC cap it quites a bit but doesnt really go away

Oh of course all 630v caps
All solder jionts have been check and doble checked .. but Ill look again.
Taped tubes till I'm blue.. no dif... but will try again after dinner.

Keep giving me Ideas pleeeese... I'm going batty here

Well, not that this sounds at all like lightning, but I do know that light dimmer noise tends to get louder sometimes when a station is tuned in. At other times it gets quieter, which is the more logical phenomenon, as a strong station would tend to overpower the AVC and reduce reception of the offending noise. However, I have noticed, as said before, that sometimes it gets louder when a station is tuned in. Hmmmmmmm..... I wonder if certain noises need a signal in order to get through properly. Afterall, you need a signal to combine with the oscillator in order to get the IF. Perhaps some interferences don't have enough of a frequency of their own to get through (yes, I know that interference is often a broad spectrum of frequencies). ....Rather silly theory of mine, but perhaps it is true. Perhaps there is something else in your home that is causing the interference. Run a few radios together on the same circuit and see if they don't all produce static.

Thomas

No Thomas... all other radios ae fine. This is like blasting crashing arching static. Like inter electrode arcing or something like that.

Same exact type noise as when B+ get on the grid from bad IF can caps...
It's that kind of random bursts of very sharp loud crashing static

You should change out all of the tubes just for the heck of it. This kind of problem might be hard to detect on a tube tester when performing an element to element shorts test, though it's worth a try. Tap the tube and watch the neon light for each element. It would be more easily found with a tube tester that had a headphone jack. You can try placing a 2000 ohm headset in series with the plate lead of each tube. This may upset normal radio performance, but it might allow you to hear crackling in a certain stage.

T.

Also, does it vary with the volume control? Could it be in the tone/band switch or the volume control? Could the voice coil be slightly rubbing against the pole piece? Could something else be slightly rubbing? These items would produce an unchanged crackle across the dial, though, so they are less likely to be the cause.

Thomas

Also, try jiggling the trimmers with a screw driver to see if one is perhaps causing trouble. On rare occasion insulation breaks down in one of these, and the screw will short across the leaves, or something else will short out (like the leaves themselves). Could even be a broken wire inside of one of the IF transformers. These things, as I recall, don't get through as easily without a signal to help them along.

T.

I alread replace the low end padder with a fixed cap. Then I already swapped out the entire 1st IF can with a spare... all to no avail.

Perhaps I should try swapping out the 2nd IF now.

But feel so helpless and a bit hapless by shot-gun troubleshooting this way.
I wish I could apply some exacting stage elimination or something.
I did try removing the local oscilator from the coupling cap C4 and injecting my own signal generator at max output.
I tuned the station to 770kc first. Then disconnected the local osc.
I then injected 1225kc from the generator and it works fine... no static.
However this is perhaps a little misleading as I can't get my output up to the same level as the local osc.
Because when I measure the osc voltage (grid pin 5 12sa7) before my injection it is up at around -8.5v
When I inject my signal generator pin 5 drops to -4.8 volts. the print shohs a range of -6 to -10 as normal.

Also it seems that under normal conditions the static isn't there or gets better on the weaker stations... and as soon as I get to the really strong stations it's the worst.

So by injecting my own signal generator and observing that the static is gone is not proving too much because the mixer is not getting the same input levels.

It does indicate that lower inputs from either the osc or the station signal will reduce it... but why?

All Tubes have been replaced as stated in my earlier post.
And the first two again from NOS. jiust to be sure.

The static increases or rides on the volume.
It is annoyingly loud at a low to normal volumre and if I turn up volume it gets louder as does the audio.

Your problem is definitely in the RF section, or at least the RF section is what is picking it up. CHeck your RF plate voltages when you get static. Also, check DC voltage on the chassis to B-. If you get any, this could tell you a lot of things.

Thomas

:The RCA 56x10 (1945 vintage)
:http://www.nostalgiaair.org/PagesByModel/992/M0014992.pdf
: ...that I just finished completely re-doing last week and now up for sale on Ebay... is exhibiting a new interesting symptom tonight.
:
:I was listening to it all night nicely... then a few minuets ago it just started to make loud static burts like lighting storm noises... almost obliterating the audio.
:
:At first I thought it was external but then it wouldn't stop.
:
:TW..( This radio has the older, conventional looking, IF cans so I don't really think they have the dangerous integrated silver mica caps in there)
:
:So anyway..
:Then I figured... since every capacitor in the radio is new... what else can it be?
:... maybe an inter-elctrode shorting problem in one of the RF tubes?
: So I tapped them with a brush handle a bit and when it stopped I thought that was it.
:.. but a few minuets later as I tuned down the dial and as soon as I got to the strongest station it started again.
:So I tried pulling the RF tubes and replacing them right on down the line till every tube in the set was changed and the static is still there.
:
:Now...Here's the real big clue....that I haven't figured out yet...lol
:
:... I noticed that as I tune across the dial it is silent until I hit a station/signal then there's loud static... but totally quiet between stations!!
:
:Now this is a strange one. My first thought is that it has something to do with the AVC circuit.
:
:But I can't see how a faulty AVC cap would cause static like this.
:
:I think that C-14 is the AVC capacitor.
:.. the print shows it as a .035uf ...( kinda weird value and also weird because I usually see .05uf)
:... anyway I had replaced the .035 uf with a .04uf which is the closest I had.
:
:So unless there is a cold solder joint or a new component quit... I have no idea for sure where to start.
:It's now about 7:30 am and I was already up all night as usual anyway and was just about ready for bed.
:.. but I'm so curious now I kinda want to start poking around in there now.
:So maybe I will. Or M A Y B E... I might just hit the sack too.
:But in the mean time.. any ideas will be apreciated... and if I do get it solved I'll certainly post it later.
:
:

Peter, Sometimes use a 0.1uf/630V polyester cap as a RF grounding probe. Easy to make, connect one lead to B- and the other lead to the probe for grounding out various points in the radio such as IF transformers, resistors, tube pins, etc. With patience and a little luck you can work out which stage is making the noise. Also can help with finding noise to a lesser degree in audio section.

Richard

OHMIGAWD….only .twee days ‘til e-Bay timeout……..Bet you’re sweating bullets now!!!
~128 Dollars worth to be even more exacting…

As I interpreted your troubleshooting the AVC line you went on the 2ND I.F. side. How’s about going to the left of the AVC dropping resistor (R6…3.3 meg) and grounding it with a short clip lead and that will let the RF-Converter-IF stages run at full unbridled gain. See if this aggravates the popping condition…also go between weaker and a very strong station.
Performing a voltage monitoring back at the AVC lug of the 2nd IF could find upwards of -30VDC at that point on a strong station. Then see if the crash poppy- poppy is any worse at one signal level… tuned on station …than another.

Another thought was looking at your photos ….
REF:
http://img84.imageshack.us/img84/716/rcaqj3.png

An initial look at one pictures angle seemed that you left a large red rust strip at one side on a rear dial support strut , but from this picture…red arrow… it seems to be a glued on cork or rubber strip ?.
But confirm for me….do I see micro red rust residue on the internal IF trimmer capacitors along with the RF ant coils compression capacitor also?
Any chance that you used a spray on cleaner on the set where there could be coincidental permeation / wicking of moisture and /or/with trace acidic or alkaline conductive components of that cleaner into unwanted area(s). If I remember right, those porcelain trimmer superstructures are of raw bisque construction….e.g….. not glazed and can wick in moisture quite readily.
Also I forget if the tube sockets might be common wafer sockets with the same unglazed conditions on the inner facing layers.
Didn’t you go through a similar situation sometime back whereupon you either got retentive moisture or a conductive flux into an unwanted area ?
If this is a retentive moisture problem, might you cook out the chassis in a low level warm home oven rack to confirm.

Sir Richard already touched upon my final thought of stage isolation by signal to ground bypassing…IF…the trouble is not triggered by virtue of a progressive gain threshold level.. However, I tend to go more all out in the audio stages by ground bypassing signal stages using upwards of a 10 ufd / 450 axial lead cap.

Aside……Got somewhat advanced age on two tubes with their top ion burns…right?

73’s de Edd

Well!!... here's the latest.. It's "sort-of" solved and fixed but by weird accidental providence.

I was trying the RF grounding probe idea and I had a .1uf cap as a probe grounded on one side and probing around with the other.

Well I didn't even get too far and I started by touching the output of the 2nd IF... (diode of 12SQ7).. then I was touching the input of the 2nd IF (plate of 12SK7) WELL... there's +90 volts there... which charged my cap/probe I guess... lol....
Then (unaware of the charged up Cap/probe) I touched the low (yellow) end of the 2nd IF ...which is also located and connected to the top of the vol control at the junction of the AVC resistor.... Then I heard a small... zap-crack!... as the cap discharged to that node!
Suddenly the static stopped completely and the signal became beautiful..loud clear and pure!!

"Fixed" ??.. not any static.. gone.!!!!!!!!!!!!

The radio plays, suddenly, kind of 'STRIKINGLY' beautifully... maybe even better than ever before but I really can't be too certain of that. Just don't recollect it ever being quite this good...lol
.. but maybe I'm clouded from the 24 hour static irritation... ANYWAY... it's working !..

BUT WHY????????????? Dear Gawd... why?

What the heck did that little ZAPPO do?

Did it remove some built up charge on C5 and C6 ???
And BTW... what the heck are those two caps tucked away into the IF can used for anyway?
So I will probably pull that 2nd IF later.. and open the can and examine those two caps and whatever else I see in the can... (tuna?.. w/mercury probably)

But so...whose to say what the "zap" fixed.. it might have traveled the other way too ...down the AVC path... WHO knows?
I am torn between glee and angst... Don't want to EVER send out a radio with an intermittent glitch. y'know?

And that would be your C5 and C6 in the shield.
C5 an I.F. decoupling filter with an additional one at C6 since there is an isolative 50K stop at the high end of the volume control. The two of them of proper Z at the IF freq, but ,of such high Z at the audio spectrum, that they produce no high frequency audio tonal shunting. That’s left for C8 in the tone shaping circuit to do.
If you find them of other than conventional sealed dipped silver mica type of construction, it might be a good PM idea to change them to a good El Menco/Arco’s of the afore mentioned type . Particularly, in the light of your BUG ZAPPING experience.

73’s de Edd

Wish it were that easy EDD:

Yep I yanked that IF can out just drooling to see what these C5 & C6 caps looked like... drool drool drool.... but all hopes were dashed..

These two caps are somehow integrated right into the one-piece ceramic structure housing the trimmers.

So I didn't get to examine them.
...all I could do was replace and resolder all the leads.
... couldn't even measure to see if they were at 120pf as shown.. as my cap meter bottoms out at 400nf.

I hate not knowing what the final resolution is to weirdo problems like this.

I mean what the heck actually happened here?

Did the .1uf home-made-probe discharge ... actually fix, or 'heal' something?
or.... as it discharged... did it also actually also suck into itself some "twilight Zone" charge that was sitting at that node... caused by some cloud of rusty electron ether-dust that needed to be drained... lol

I vote in favor of the zap perhaps...actually, sort of 'healing' one of those caps in that IF can.. it may have reformed them ... I don't really know.. but if they were not working properly would they prevent the proper drainage of static charge build-up??

My hope now is twofold.

1.) That it comes back by steady play in the next couple days... and I can chase it down.
or
2.) That it NEVER rears it's ugly head again..... like an ex-wife...

Yes, those capacitors are integral to the trimmer. They probably aren't causing any trouble, but it is possible. Also, did you replace/test any of your micas? Trouble in the oscillator/converter section due to arcing micas will not show up past the IF section unless it has a signal to ride on (combine frequency with). Regarding those micas, it's a good idea to check voltages when the crackling starts. Arcing micas will cause the voltage to jitter up and down (AVC will of course jitter, too, because of the change in signal strength due to the crackling). The best way to test the micas is with a separate 200 volt power supply and a volt meter.

This probably isn't your trouble, but my RCA 55X (or maybe it's 55X2....I forgot), which is basically the same radio as your's, except without short wave, has a similar trouble. Sometimes it'll pop and go into this static crashing/rushing sound. If I turn it off and back on, the problem goes away.

Thomas

Well next time that happens to your RCA and you can troubleshoot it..I'd love to know what it is for sure.

Maybe since C5 and C6 are also all integrated in the same substrate as the IF trimmers... isn't it possible that there is some kind of failure or cross cap leakage in there similar to the dreaded silver mica disease problem?

It certainly provides an answer to how the B+ can sneak accross the caps to and get onto the input of the next stage.
And the crashing random static is identical to the same problem.

:Well next time that happens to your RCA and you can troubleshoot it..I'd love to know what it is for sure.
:
:Maybe since C5 and C6 are also all integrated in the same substrate as the IF trimmers... isn't it possible that there is some kind of failure or cross cap leakage in there similar to the dreaded silver mica disease problem?
:
:It certainly provides an answer to how the B+ can sneak accross the caps to and get onto the input of the next stage.
:And the crashing random static is identical to the same problem.
:
Peter,

Perhaps you could unsolder the black and brown leads and attach a 120 pf mica from the yellow IF lead to ground and another from the center terminal of the volume control to ground. Then turn the radio on and see if the noise is still there.

Radiodoc

Well RadioDoc:
The noise already did go away as I posted above... it was just after I was probing with a .1uf cap to ground. I touched the plate of the 12sk7 B+ and that charged the cap ...then as I touched the top of the vol control pot where the AVC resistor is.. I heard a zap as the cap dicharged into that node.. and instantly the noise disapeared!!!!!!!!!
Hasn't come back.
But I agree that would work just as insurance for me to get those two caps physically out of the IF can and have the comfort of knowing that it won't be part of a prob in the future.
Good.
Thanks..

:Well RadioDoc:
:The noise already did go away as I posted above... it was just after I was probing with a .1uf cap to ground. I touched the plate of the 12sk7 B+ and that charged the cap ...then as I touched the top of the vol control pot where the AVC resistor is.. I heard a zap as the cap dicharged into that node.. and instantly the noise disapeared!!!!!!!!!
:Hasn't come back.
:But I agree that would work just as insurance for me to get those two caps physically out of the IF can and have the comfort of knowing that it won't be part of a prob in the future.
:Good.
:Thanks..
:
Peter,

That's what I was hinting to. In years past I have found when a problem disapeared on its own that I would be revisiting it again sooner or later. Generally sooner.

Radiodoc

I kind of doubt that it's those caps, though. They're actual pieces of metal between pieces of mica. They're rigid and strong, and aren't likely to migrate. If you want, you can clean the condenser with mineral spirits. Then clean with soap and water. This will remove any grime that might cause leakage and noise. If things looked grimy to begin with (chassis), then it is likely that the condensers in the IF are grimy. With the set-up of these IF transformers, there is no way for voltages to migrate from primary to secondary, if anyone is wondering about that. The trimmers are well mounted way across from eachother, with lots of porcelain between them. If the porcelain was grimy, leakage might occur. It is important to insulate the terminals from the can, though. Manufacturers sometimes place a paper shroud over the porcelain assembly. This shroud extends down over the terminals.

I can't really say what the problem is with my RCA, other than that it is probably due to a failing condenser. My radio has all of its original condensers and resistors except for the electrolytics. It usually works fine, but sometimes pops into a rushing sound. When I used to listen to AM more, I used to use it a ton. I still use it now and then, and it always works well except for when it starts rushing. The correction for this is to turn it off and back on again. The more permanent correction would be, of course, to replace all of the condensers. Someday I will do this, but I don't have the extra time right now. There are many other things waiting on my back burner.

Thomas