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National NC-125 RF Alignment




 
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KW4H
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« on: June 20, 2022, 04:36:33 PM »

I'm aligning the RF section of a NC-125 that's WAY out of alignment, and it's proving to be quite the task.  On the "A" band I can get a good alignment at the top end (34 MHz), and the image is above the fundamental as required.  The lower end (12 MHz) won't align because the slug in the coil has been seriously misaligned.  I'm trying to find the right balance between the trimmer capacitor (upper frequency) and inductor (lower frequency) but am not having much luck.  Does anyone know of any tricks to getting this relationship set correctly?

73 - Steve, KW4H
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W7TFO
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IN A TRIODE NO ONE CAN HEAR YOUR SCREEN


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« Reply #1 on: June 20, 2022, 08:13:42 PM »

I'm not sure about your National, but some RX cal with the bandspread set at the top of the dial.

 DG
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K9MB
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« Reply #2 on: June 20, 2022, 11:59:20 PM »

I'm aligning the RF section of a NC-125 that's WAY out of alignment, and it's proving to be quite the task.  On the "A" band I can get a good alignment at the top end (34 MHz), and the image is above the fundamental as required.  The lower end (12 MHz) won't align because the slug in the coil has been seriously misaligned.  I'm trying to find the right balance between the trimmer capacitor (upper frequency) and inductor (lower frequency) but am not having much luck.  Does anyone know of any tricks to getting this relationship set correctly?

73 - Steve, KW4H


You may already have this manual from BAMA, but it does have an alignment procedure for the NC125 in it, in case you do not.
Alignment of any receiver has to be done in sequence or it can be very difficult to get right.

If slugs are at extremes, it is usually a sign that somebody just put a signal in the antenna jack and started turning slugs and screws. Not a good idea…

https://bama.edebris.com/download/national/nc125/nc125.pdf
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KW4H
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« Reply #3 on: June 21, 2022, 09:08:08 AM »

Thanks, all.  I do have the manual and have been following the usual instructions.  The problem with this particular NC-125 is that the RF alignment is seriously out of whack.  The alignment instructions in National's manual assume that only slight tweaking might be needed. 
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Carl WA1KPD
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« Reply #4 on: June 21, 2022, 11:55:42 AM »

Maybe someone with a working one could give you the approximate slug depth? Absent that I would start with them at mid-point and work slowly from there.

Nice RX BTW
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Carl

"Okay, gang are you ready to play radio? Are you ready to shuffle off the mortal coil of mediocrity? I am if you are." Shepherd
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« Reply #5 on: June 21, 2022, 02:42:18 PM »

Maybe someone with a working one could give you the approximate slug depth? Absent that I would start with them at mid-point and work slowly from there.

Nice RX BTW

Thanks, I should have thought of that!  I have a second NC-125 (of unknown operational condition, but it appears to be mostly unmolested), and I opened it up to check the slug position for L-8.  Putting the slug in approximately the same position didn't solve the problem.  However, upon closer inspection it appears that L-8 might be somewhat compromised in this set through over-adjustment in the past.  The inside of the coil form appears to be quite worn, and inductor wiring marred from too much up-and-down motion of the slug.  It's a simple inductor to rewind by hand, which I may do.  One of the challenges with these old radios is that some of them have been nearly beaten to death over the decades by mad scientists. 

73 - Steve, KW4H
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K9MB
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« Reply #6 on: June 22, 2022, 11:18:29 AM »

Maybe someone with a working one could give you the approximate slug depth? Absent that I would start with them at mid-point and work slowly from there.

Nice RX BTW

Thanks, I should have thought of that!  I have a second NC-125 (of unknown operational condition, but it appears to be mostly unmolested), and I opened it up to check the slug position for L-8.  Putting the slug in approximately the same position didn't solve the problem.  However, upon closer inspection it appears that L-8 might be somewhat compromised in this set through over-adjustment in the past.  The inside of the coil form appears to be quite worn, and inductor wiring marred from too much up-and-down motion of the slug.  It's a simple inductor to rewind by hand, which I may do.  One of the challenges with these old radios is that some of them have been nearly beaten to death over the decades by mad scientists. 

73 - Steve, KW4H

If I am reading the schematic correctly, L8 is the oscillator coil for the first mixer-which is a 6SB7 Pentagrid converter similar to a 6BE6 used in later designs.
If L8 is out of alignment, it would prevent the oscillator from tracking or not able to reach the range required.
It is an iron core coil, and it is not clear to me if the core is bonded to a brass screw. If the adjustment was just in the core, an idiot with the wrong tool could erode the core or break out  and make it difficult to shift it.

There are other perils too, like bad connections internally to windings if the coils have been abused.

Is the difficulty a tuning range issue or a gain tracking issue? I was not clear there.
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KW4H
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« Reply #7 on: June 22, 2022, 05:48:55 PM »


If I am reading the schematic correctly, L8 is the oscillator coil for the first mixer-which is a 6SB7 Pentagrid converter similar to a 6BE6 used in later designs.
If L8 is out of alignment, it would prevent the oscillator from tracking or not able to reach the range required.
It is an iron core coil, and it is not clear to me if the core is bonded to a brass screw. If the adjustment was just in the core, an idiot with the wrong tool could erode the core or break out  and make it difficult to shift it.

There are other perils too, like bad connections internally to windings if the coils have been abused.

Is the difficulty a tuning range issue or a gain tracking issue? I was not clear there.

In the alignment process for the "A" band (12 - 34 MHz), C-18 is adjusted for the upper end and L-8 is adjusted for the lower end.  Those two adjustments work together to create the correct tracking, but one affects the other.  I can tell that L-8 is functioning - somewhat - because if I adjust L-8 a little after adjusting C-18, the upper frequency tracking changes.  The issue is that L-8 refuses to cooperate with the 12 MHz test signal -- it's just a big nothing.  After adjusting C-18 the upper end of the "A" band is hot, but as you roll down the band in frequency, the reception becomes weaker as you get about a third of the way down the dial, then weaker again around 14 or 15 MHz, and then below that the NC-125 is deaf and adjusting L-8 achieves nothing.

Looking inside the L-8 coil form, there is a brass screw bonded to the bottom of the core.  I've gently adjusted the core one way or the other and, although the receiver is totally deaf at 12 MHz, I have noticed intermittent behavior at the higher frequencies around 14 or 15 MHz.  As you move the core, the received test signal (AM-modulated w/ a 400 Hz tone) will suddenly jump in and out of existence.  This happens when the core (and its brass adjustment screw) gets on or near the windings that pass to the inside of the coil form.  

I believe what may be happening here -- and I don't want to jump to conclusions -- is that the brass adjustment has been jacked with so much over the years that it's removed insulation from coil leads inside the form.  This may be abruptly altering the inductive value of L-8 and creating a situation where the coil won't resonate as it should.  But again, I don't want to assume -- that's bit me numerous times in the past.  

The wiring to L-8 is solid and I've confirmed there are no intermittents there.

As an aside, the NC-125 is an interesting beast.  It was manufactured for SIX years (1950-56), and a lot were presumably sold, yet there seems to be virtually nothing out there on it except the original manual and a SAMS Photofact.  I did a deep search of QST publications, as well as CQ and 73 Magazine.  Zero, except for old National ads where they sold the NC-125 alongside the HRO-50-1 -- I suppose as a cheaper alternative.  There is one article in ER Magazine (#278 - July 2012), which is a good read, but I was hoping to find some articles with a little more technical depth.  

73 - Steve, KW4H
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Carl WA1KPD
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« Reply #8 on: June 22, 2022, 08:05:11 PM »

This happens when the core (and its brass adjustment screw) gets on or near the windings that pass to the inside of the coil form.  

I believe what may be happening here -- and I don't want to jump to conclusions -- is that the brass adjustment has been jacked with so much over the years that it's removed insulation from coil leads inside the form.

Not to say it isn't the case, but I've never seen a case where the core rubs against any inside leads. I wonder if the slug is starting in the wrong spot, It would just seem unlike National Engineering to allow that.

Googeling your symptoms I came across this answer to a BC set issue similar to yours.

"This is a long shot, but it could happen.  While aligning, you might have accidentally set the LO for  low side, not high-side injection.  Remember that the set would work at 1600 KHz if the LO were operating at either 2055 OR 1155.  BOTH would produce the 455 KHz IF.  This is especially true if the oscillator trimmer is very, very tight.  If this is the case, the LO would be 1145 KHz at the high end of the band, and the set would still receive stations above about 1000 KHz.  Sensitivity would get progressively worse as you tune down the dial as antenna circuit bandwidth narrows.  At some point, the LO could drop out entirely, rendering the set inoperable..  You can check LO frequency using either oscilloscope or transistor-radio (or short wave receiver)."
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Carl

"Okay, gang are you ready to play radio? Are you ready to shuffle off the mortal coil of mediocrity? I am if you are." Shepherd
KW4H
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« Reply #9 on: June 22, 2022, 09:06:19 PM »

This happens when the core (and its brass adjustment screw) gets on or near the windings that pass to the inside of the coil form.  

I believe what may be happening here -- and I don't want to jump to conclusions -- is that the brass adjustment has been jacked with so much over the years that it's removed insulation from coil leads inside the form.

Not to say it isn't the case, but I've never seen a case where the core rubs against any inside leads. I wonder if the slug is starting in the wrong spot, It would just seem unlike National Engineering to allow that.

Googeling your symptoms I came across this answer to a BC set issue similar to yours.

"This is a long shot, but it could happen.  While aligning, you might have accidentally set the LO for  low side, not high-side injection.  Remember that the set would work at 1600 KHz if the LO were operating at either 2055 OR 1155.  BOTH would produce the 455 KHz IF.  This is especially true if the oscillator trimmer is very, very tight.  If this is the case, the LO would be 1145 KHz at the high end of the band, and the set would still receive stations above about 1000 KHz.  Sensitivity would get progressively worse as you tune down the dial as antenna circuit bandwidth narrows.  At some point, the LO could drop out entirely, rendering the set inoperable..  You can check LO frequency using either oscilloscope or transistor-radio (or short wave receiver)."

Thanks for the reply!  In the case of the NC-125 the oscillator function is all wrapped up inside the 6SB7-Y pentagrid converter tube and there isn't a LO -- at least not in the classic sense.  I've done very little work with these self-oscillating mixers over the years -- which is a shame, they're quite intriguing.  The oscillator section of the tube is the cathode, first control grid, and the combined screen grids as the anode. 

73 - Steve, KW4H
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K9MB
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« Reply #10 on: June 23, 2022, 02:01:08 AM »


If I am reading the schematic correctly, L8 is the oscillator coil for the first mixer-which is a 6SB7 Pentagrid converter similar to a 6BE6 used in later designs.
If L8 is out of alignment, it would prevent the oscillator from tracking or not able to reach the range required.
It is an iron core coil, and it is not clear to me if the core is bonded to a brass screw. If the adjustment was just in the core, an idiot with the wrong tool could erode the core or break out  and make it difficult to shift it.

There are other perils too, like bad connections internally to windings if the coils have been abused.

Is the difficulty a tuning range issue or a gain tracking issue? I was not clear there.

In the alignment process for the "A" band (12 - 34 MHz), C-18 is adjusted for the upper end and L-8 is adjusted for the lower end.  Those two adjustments work together to create the correct tracking, but one affects the other.  I can tell that L-8 is functioning - somewhat - because if I adjust L-8 a little after adjusting C-18, the upper frequency tracking changes.  The issue is that L-8 refuses to cooperate with the 12 MHz test signal -- it's just a big nothing.  After adjusting C-18 the upper end of the "A" band is hot, but as you roll down the band in frequency, the reception becomes weaker as you get about a third of the way down the dial, then weaker again around 14 or 15 MHz, and then below that the NC-125 is deaf and adjusting L-8 achieves nothing.

Looking inside the L-8 coil form, there is a brass screw bonded to the bottom of the core.  I've gently adjusted the core one way or the other and, although the receiver is totally deaf at 12 MHz, I have noticed intermittent behavior at the higher frequencies around 14 or 15 MHz.  As you move the core, the received test signal (AM-modulated w/ a 400 Hz tone) will suddenly jump in and out of existence.  This happens when the core (and its brass adjustment screw) gets on or near the windings that pass to the inside of the coil form.  

I believe what may be happening here -- and I don't want to jump to conclusions -- is that the brass adjustment has been jacked with so much over the years that it's removed insulation from coil leads inside the form.  This may be abruptly altering the inductive value of L-8 and creating a situation where the coil won't resonate as it should.  But again, I don't want to assume -- that's bit me numerous times in the past.  

The wiring to L-8 is solid and I've confirmed there are no intermittents there.

As an aside, the NC-125 is an interesting beast.  It was manufactured for SIX years (1950-56), and a lot were presumably sold, yet there seems to be virtually nothing out there on it except the original manual and a SAMS Photofact.  I did a deep search of QST publications, as well as CQ and 73 Magazine.  Zero, except for old National ads where they sold the NC-125 alongside the HRO-50-1 -- I suppose as a cheaper alternative.  There is one article in ER Magazine (#278 - July 2012), which is a good read, but I was hoping to find some articles with a little more technical depth.  

73 - Steve, KW4H

Again-if I am not mistaken, L8 only affects the frequency of the oscillator section of the pentagrid converter.
The only thing that must be known is whether you are getting tracking of the injection frequency across the band,
I believe that it is single conversion so the oscillator frequency will be 12 + 0.455. To 34 + 0.455.

If the receiver has less “soup” at 12mhz, then that is related to the input tuning for the RF amplifier feeding the signal grid of the converter.
If you are not able to get the oscillator to go low enough, then L8 might have a bad slug. Since it has brass studs, this is less likely to be a bad core, though it could be broken or cracked. Can you pull it out?
You could kluge the circuit with a fixed toroid coil, if you need a bit more inductance and want performance, not the stock perfection of full restoration.
The value of L8 is not listed, so experimentation would be needed to try this kluge.
For gain balance tracking adjust the rf circuits as instructed.

Just thought- have you tested the pentagrid converter tube?
A bad tube could affect injection, though it is usually the high frequencies most affected by a weak tube.

Edit: 10am 06-23-22
Just touching bases here.
The weak signal at 12 mHz is likely related to the settings and status of L1. And L20
If you look at the notes, you have to set L1 and L20 at 12mHz L1 is a double tuned circuit, so likely you have to adjust on top and bottom and L20 is only adjustable at bottom of can and it says (loop). MAybe there is a secondary series winding at the bottom and the iron core has to be in the adjustment range that allows it to be peaked.
Also their is interaction with C5 and C12, so if those caps are way out, it will make it impossible to find the correct combination at both ends. You have to go back by forth to bring up the 12mHz end and then find balance by tweaking all tjese adjustments. It is obviously way out of whack.
Look on your second NC-125 at the adjustment of the bottom of L20 and L1 for clues to begin.
Never worked on this receiver, but have done others even more complicated, but when some idiot gets some tools and no brains, it can get really difficult to resurrect…
Kind of fun when you win, though, so keep at it…😉
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KW4H
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« Reply #11 on: June 23, 2022, 03:54:43 PM »


Again-if I am not mistaken, L8 only affects the frequency of the oscillator section of the pentagrid converter.
The only thing that must be known is whether you are getting tracking of the injection frequency across the band,
I believe that it is single conversion so the oscillator frequency will be 12 + 0.455. To 34 + 0.455.

If the receiver has less “soup” at 12mhz, then that is related to the input tuning for the RF amplifier feeding the signal grid of the converter.
If you are not able to get the oscillator to go low enough, then L8 might have a bad slug. Since it has brass studs, this is less likely to be a bad core, though it could be broken or cracked. Can you pull it out?
You could kluge the circuit with a fixed toroid coil, if you need a bit more inductance and want performance, not the stock perfection of full restoration.
The value of L8 is not listed, so experimentation would be needed to try this kluge.
For gain balance tracking adjust the rf circuits as instructed.

Just thought- have you tested the pentagrid converter tube?
A bad tube could affect injection, though it is usually the high frequencies most affected by a weak tube.

Edit: 10am 06-23-22
Just touching bases here.
The weak signal at 12 mHz is likely related to the settings and status of L1. And L20
If you look at the notes, you have to set L1 and L20 at 12mHz L1 is a double tuned circuit, so likely you have to adjust on top and bottom and L20 is only adjustable at bottom of can and it says (loop). MAybe there is a secondary series winding at the bottom and the iron core has to be in the adjustment range that allows it to be peaked.
Also their is interaction with C5 and C12, so if those caps are way out, it will make it impossible to find the correct combination at both ends. You have to go back by forth to bring up the 12mHz end and then find balance by tweaking all tjese adjustments. It is obviously way out of whack.
Look on your second NC-125 at the adjustment of the bottom of L20 and L1 for clues to begin.
Never worked on this receiver, but have done others even more complicated, but when some idiot gets some tools and no brains, it can get really difficult to resurrect…
Kind of fun when you win, though, so keep at it…😉

All very good thoughts, thanks.  This exchange is jogging my memory (been working on other projects for a while, and now I remember why).  The front end of this NC-125 was, in fact, a bloody disaster when I originally got the radio a year or two ago.  L-1 and the area around it was particularly messy (cut wires, added parts flapping in the breeze, missing components, etc).  It was all hidden behind the bottom cover.  I had two choices:  part it out (which I hate to do) or "go for it".  So, I went for it.  To make a long story short, I had to disassemble the entire front end (the band switch assembly), clean everything up, trace everything out and replace missing parts.  L-1 wouldn't find a peak and had to be removed and rewound.  Rewinding L-1 was easy enough, but it still wouldn't find a peak.  All four trimmer caps were replaced in the oscillator section. All of the circuits around the RF amplifier and converter tube bases were checked, cleaned up, and components replaced.  I have a number of 6SB7Y tubes and none make a difference -- it's not the tube.

The NC-125 is definitely operating much better than when I got it, this is potentially very close to being restored.  Looking at the schematic again, the oscillator section is Hartleys (tapped coils).  I need to find out if this problem is due to the oscillator section not working right (L-8), or the RF section is still sick.  I'm going to inject a 12 MHz signal into the antenna connection and monitor with a spectrum analyzer at the trimmer capacitor.  I should see L-1 peak at 12 MHz.  If it won't find a peak, I won't start drinking heavily but will consider it.  LOL

Steve, KW4H
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KW4H
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« Reply #12 on: June 25, 2022, 06:56:51 PM »

An update and a theory to run by ya'll.  I gave the NC-125 the "poke test" and eventually located the problem with L-8.  The cause was an intermittent at one of the band switch wafers.  Some additional cleaning and a tiny dot of Deoxit took care of that issue, and now the 12 MHz signal is received and can be peaked with L-8.  L-1 still won't find a peak, though, and that's after TWO rewindings of that coil.  My guess is that it isn't L-1 itself, but possibly something related to the S-1A or S-1B wafer switches.  I've thoroughly cleaned those contacts and the wiggle tests provide nothing, however.

I think it's time to take a step back and assess what I'm actually dealing with.  And I think I know what it is, but would like to run it by the group here.  When I got this NC-125 it was a mess, and that included the bandswitch assembly.  Those wafer switches, and the entire area around them, showed clear signs of having been sprayed with contact cleaner.  Lots of contact cleaner.  I've done a proper and safe cleaning, but I can't always undo what others may have done.  Based on the behavior of the radio -- massive static on all bands that drown out signals, strange microphonics that change if you simply wiggle the chassis, and intermittent bandswitch behavior, I believe there's a possibility that the bandswitch has been ruined with cleaner sprays.  Cleaners can soak into the somewhat absorbent wafers and cause strange behavior, including small conductive paths within the wafers that can be noisy.  If it's bad enough, it can't be fixed.  People have even been known to spray WD-40 onto those switches, or to spray large amounts of Deoxit, which is particularly awful.

I have another NC-125 that appears to be all factory original.  My suspicion is that the end of the line has been reached with this one and maybe it's good for some parts donation to the other NC-125.  I've had radios fight me, but never like this.  I've heard stories about destroyed wafer switches but never actually seen one.

Thoughts?

73 - Steve, KW4H
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K9MB
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« Reply #13 on: June 26, 2022, 12:05:07 PM »

An update and a theory to run by ya'll.  I gave the NC-125 the "poke test" and eventually located the problem with L-8.  The cause was an intermittent at one of the band switch wafers.  Some additional cleaning and a tiny dot of Deoxit took care of that issue, and now the 12 MHz signal is received and can be peaked with L-8.  L-1 still won't find a peak, though, and that's after TWO rewindings of that coil.  My guess is that it isn't L-1 itself, but possibly something related to the S-1A or S-1B wafer switches.  I've thoroughly cleaned those contacts and the wiggle tests provide nothing, however.

I think it's time to take a step back and assess what I'm actually dealing with.  And I think I know what it is, but would like to run it by the group here.  When I got this NC-125 it was a mess, and that included the bandswitch assembly.  Those wafer switches, and the entire area around them, showed clear signs of having been sprayed with contact cleaner.  Lots of contact cleaner.  I've done a proper and safe cleaning, but I can't always undo what others may have done.  Based on the behavior of the radio -- massive static on all bands that drown out signals, strange microphonics that change if you simply wiggle the chassis, and intermittent bandswitch behavior, I believe there's a possibility that the bandswitch has been ruined with cleaner sprays.  Cleaners can soak into the somewhat absorbent wafers and cause strange behavior, including small conductive paths within the wafers that can be noisy.  If it's bad enough, it can't be fixed.  People have even been known to spray WD-40 onto those switches, or to spray large amounts of Deoxit, which is particularly awful.

I have another NC-125 that appears to be all factory original.  My suspicion is that the end of the line has been reached with this one and maybe it's good for some parts donation to the other NC-125.  I've had radios fight me, but never like this.  I've heard stories about destroyed wafer switches but never actually seen one.

Thoughts?

73 - Steve, KW4H

I have wondered about bad switch connections causing the lack of ability to peak the tuning.
I do not know how visible the wires are to the wagers, but soldering temporary thin wire jumpers across the questionable wafers might allow you to isolate the bad connections.
If it is the wafer switch contact, that will bypass the bad connection.
As for contamination causing wafers to absorb moisture. If they are bakelite composite, they will not absorb water and I doubt that steatite would either.
Using WD-40 on switches makes me cringe, however….😬😬🙄
Those pops and microphonics are another level of difficulty.
Best solve things one at a time.
Bypass questionable wafer switch contacts and see if it peaks and then you have the option of seeing if you can find a replacement wafer. Good luck on that.

One possibility is that the Chinese make 1 pole 4 position switches in steatite that look good. Below are two links to get them at about $7-$9 each deck.

The challenge here is to stack them to make them into a 3 Deck switch woth the same spacing as your National stock switch.
If you are really lucky, you might find that the original shaft will slide through the rectangular wafer holes. The shaft comes through the wafer far enough so you could use a coupler to tie into the deck behind.
You will need two pieces of threaded rod that fits too and a bunch of nuts to tie it together. The detent ring on the back two decks might need to be bent down so it rotates easily, relying on the front detent for alighnment…
Maybe you will get lucky and find some NOS wafers to just install, but that might be too much to hope for.
You may be forced-in the end- to canabalize on NC-125 to save the other. 50-60 years later, we all need pathch solutions at times…😉

https://www.harfington.com/products/p-1205352?currency=USD&variant=42124622102777&utm_medium=cpc&utm_source=google&utm_campaign=Google%20Shopping&utm_source=google&utm_medium=cpc&utm_campaign=pmax_us_hw_pc_ecswitch_220614&utm_content=zlt&gclid=CjwKCAjwh-CVBhB8EiwAjFEPGd8YvdO0HnqrgxblcvWq9jxbgj5b-N7sJI0ItUA7PkMSermSy0kH9hoCdHUQAvD_BwE

At Amazon:
https://www.amazon.com/uxcell-Position-Channel-Rotary-Selector/dp/B07JM3GWQ4/ref=sr_1_4?crid=32GDK4TOLB9C6&keywords=1+pole+4+position+rotary+switch&qid=1656258490&sprefix=1+pole+4+position%2Caps%2C168&sr=8-4



Edit: This 4 Deck switch might be adapted. It has 8 steps so if you use every other one, you might get 4 steps at close to the correct indexing angle so pointers line up.

https://www.amazon.com/dp/B07JKWCJ26/ref=sspa_dk_detail_2?psc=1&pd_rd_i=B07JKWCJ26&pd_rd_w=1K4Ni&content-id=amzn1.sym.999c0877-3704-4f0f-9726-eebf80846a35&pf_rd_p=999c0877-3704-4f0f-9726-eebf80846a35&pf_rd_r=9FRZFYXMDW43W9EM07VR&pd_rd_wg=pSZVr&pd_rd_r=38a7ef24-2f91-4645-a9a2-d965c7363847&s=hi&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUE3UFNPODBYSEVMNTcmZW5jcnlwdGVkSWQ9QTAzMTkzMzAxS0ROOFVXTFk2VzExJmVuY3J5cHRlZEFkSWQ9QTA2NTQ4MDIyVlZPNldFNEtOUUNYJndpZGdldE5hbWU9c3BfZGV0YWlsJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==
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