Re: SR-150 VFO Lubrication
I recently went through my SR-500 Tornado to clean and lubricate gearing in an attempt to make the tuning smoother. ?I used alcohol on a paper towel to wipe the two "wheels" that go in-between the friction gear plates, holding the paper towel on the wheel before it goes into the friction plates, and turning the tuning knob many times. ?I wanted to make sure there would be no slipping or stiffer tuning due to old grease or oily buildup. ?Then I used a stiff brush and alcohol to scrub any old grease from the meshing gears on the frequency dial. ?Then I used a little bit of sewing machine oil on the gears. ?Yes, I know that grease is most often recommended but I felt the sewing machine oil would result in a tad smoother feel. ?
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The tuning did improve a bit. ?I think there is only so much one can do with friction gearing to make it smooth. ?Not sure I'd even use the word "smooth" when talking about friction gearing.. hi hi.
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My buddy Don N9OO has also been going through his SR-150 gearing as well, and he pointed out to me that there is a nut applying a spring tension the friction gear. ?Neither of us wanted to mess with that although I've read where that is an option to adjust tension if the gear is slipping.
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Now I just bought an SR-160 that I believe has never been restored. ?The frequency tuning was significantly stiffer, so now I had a comparison. ?My Tornado tuning almost felt "smooth" compared to the SR-160, so that just tells you how stiff the SR-160 tuning is. hi hi.?
73, Scott WA9WFA
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Re: Audio Gain Pot-Replacement
Greetings to George and the Group:
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The "lip" on the edge of the panel presents some additional difficulty, but is not insurmountable.
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Here's how I changed the volume pot on my Hammarlund HQ-129 (from ARF):
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After putting up with a horrible volume control in my HQ-129-X receiver for years, I finally got around to replacing it.
( I have had the replacement pot in stock now for at least a couple of years, but it works superbly and was a good fit..... Thanks to Mark Oppat.)
The problem is that the HQ-129-X has a front panel that is spaced about 1/8" from the front chassis apron. Several of the controls (including the volume control) mount to the chassis with nuts and the shafts extend through the hole in the front panel to receive the knob. It would appear that the normal procedure would be to remove the front panel in its entirety in order to access the control mounting nut.
I really didn't feel like doing this so I made a wrench out of heavy gauge sheet metal. This allowed me to insert the wrench into the narrow gap and loosen the nut. The nut could then be unscrewed by poking the flats with a small screwdriver. Before removing the nut all the way, I taped some hook-up wire to the pot shaft. As I pulled the old pot out, the wire followed, trapping the nut more or less in place. I then taped the wire to the shaft on the new pot and fed the pot shaft through the hole in the chassis. The wire allowed me to position and re-start the nut with little difficulty. Once the pot was in position, the nut was tightened with the home-made wrench.
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The moral is that the special tool (home-made) is your friend.?? Either fabricate an "S" bend wrench out of flat stock or get out your torch and bend a cheapie end wrench of the correct size from Harbor Freight.?? Be sure to use the wire trick.?? If you can't get a small screwdriver in to turn the nut once it is loose, a large diameter soda straw or similar piece of tubing can be slid over the wire and then the pot shaft and through the outer panel to remove the nut.?? After inserting the new pot, start the nut with the tubing and tighten with the custom wrench.?? After all is done, then and ONLY then, remove the locating wire.
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Good Luck,
--
Jim T.
KB6GM
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Re: Removing HT-32B SSB Generator Subchassis
We'll be watching, Don! 73 John K5MO On Fri, May 2, 2025 at 6:25?PM Don Buska - The Radio Lab Works via <don= [email protected]> wrote:
Does anyone know if the
HT-32B SSB Generator subchassis can be removed without removing
the front panel?? On my restoration I want to replace, at least,
C7 a dual 10uF 350V Electrolytic,? Sadly the screws that hold on
the cover of this sub-unit can not be removed with the unit inside
the transmitter.?
I got this picture off the web of K3MSB's HT-32 disassembled.? As
you can see they have elongated holes on the chassis to allow the
SSB Generator to be swung out from the top side after removing
four 1/4" nut head machine screws.? I'm afraid to say I don't
think it will be possibly to perform this swing routine without
removing that front panel (Power transformer is in the way).
K3MSB's Picture (HT-32)
Just wanting to confirm with the experienced among you.? I plan on
taking many pictures along the way for future documenting on the
web too.? BTW, I'm
not afraid to remove the front panel.?? It looks easy too.
73
Don N9OO
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Removing HT-32B SSB Generator Subchassis
Does anyone know if the
HT-32B SSB Generator subchassis can be removed without removing
the front panel?? On my restoration I want to replace, at least,
C7 a dual 10uF 350V Electrolytic,? Sadly the screws that hold on
the cover of this sub-unit can not be removed with the unit inside
the transmitter.?
I got this picture off the web of K3MSB's HT-32 disassembled.? As
you can see they have elongated holes on the chassis to allow the
SSB Generator to be swung out from the top side after removing
four 1/4" nut head machine screws.? I'm afraid to say I don't
think it will be possibly to perform this swing routine without
removing that front panel (Power transformer is in the way).
K3MSB's Picture (HT-32)
Just wanting to confirm with the experienced among you.? I plan on
taking many pictures along the way for future documenting on the
web too.? BTW, I'm
not afraid to remove the front panel.?? It looks easy too.
73
Don N9OO
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Re: Working on HT-32B & Weight Lifting
You should try working on an R-390a! k6lr
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Re: HA-1 T.O. Keyer socket gnds
I have seen center post to ground as high as 150 ohms. It only takes 3 to 5 ohms to start causing problems with speed and weight. It has the biggest effect on the timing capacitors.
Walt Cates, WD0GOF
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A majority of acceptance is not proof of correctness.
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Very good, Walt.? Glad to see you point out the problem with the tube socket grounds.? Years ago my HA-1 became erratic - code elements missing or the wrong length.? It took me many days before I discovered a faulty ground at a tube socket - it looked
perfect but must have had a high resistance.??
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73, Floyd - K8AC
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Re: Audio Gain Pot-Replacement
Thats a thought Jim.? I don't think I could even get some kind of spray into it.? See an earlier post where I addressed the placement of the pot.? Its well hidden!
Keep thinking for me of ideas!? Murphy had things right!? THANKS, George KN3PAT
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Re: Audio Gain Pot-Replacement
There is NO nut at the front panel!? There is the front panel, then another front panel behind the real front panel.? There is perhaps 3/8 in. between the two.? The nut on the pot is on the second panel.? The pot is kind of buried behind both panels.? To make it harder, there is a "lip" at the bottom of everything!? I think I replaced the pot maybe 40 or so years ago! ? There are a total of 15 knobs and switches that would have to be removed to get the front off.? They use a special wrench-a"Bristol" which I have. I was much younger, and dumber then.? At 78 I'm not sure I really feel like attacking this job!? I am not familiar with fade lube, but if you need to get it on the inside of the pot-good luck!? I have not really tried anything yet, because I dont see any real option other then replacement because of access!? I was hoping someone might have some thought on an easy removal!? These old Hallies are built like battle ships-maybe that's why after 65 years they still work well! Check out my QRZ page to see my collection of them! Keep thinking about this for me!? Any thoughts are appreciated! THANK YOU! George KN3PAR
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Very good, Walt.? Glad to see you point out the problem with the tube socket grounds.? Years ago my HA-1 became erratic - code elements missing or the wrong length.? It took me many days before I discovered a faulty ground at a tube socket - it looked perfect but must have had a high resistance.??
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73, Floyd - K8AC
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Re: Working on HT-32B & Weight Lifting
oh yes well fit youth. brings back memories of the early 60's as
a 16 yr old ham lugging my WRL 350A onto the bench and then back
to the op desk. hihi..The L4B power supplies keep getting heavier.
have a Chippawal waiting in the wings to be restored. may have to
buy an A frame for that one. took two of us to unload the power
supply.
catching up to you fast Walt.
73 Tony WA4JQS 78
On 5/2/2025 11:20 AM, waltcates via
groups.io wrote:
At 82, I call my son when I want to move the P2000.
Walt Cates, WD0GOF
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A majority of acceptance is not proof of correctness.
I just got done emailing a good friend, about my initial start
up work on the restoration of a HT-32B and how extremely heavy
it was for this old man, I'm 66, to carry it ten feet over to my
repair bench.? Having just completed restoration on the
SR-150/SP-150 pair it has been an eye opener.
._,_
--
Anthony W.DePrato WA4JQS
CQ DX HALL OF FAME #39
DXCC HONOR ROLL CW PHONE RTTY
CALLS HELD VP8SSI VP8BZL V31SS 3Y0PI ZS8JQS WA4JQS/KC4 WA4JQS/ZS1
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Re: Audio Gain Pot-Replacement
George, what are you looking for? A way to remove and replace the potentiometer without removing the front panel?
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It might be possible, I did it once years ago. Is there a nut between the chassis and front panel? I was able to find a thin 1/2" wrench (A stamped one about 3/32 thick) that could hold the nut. After removing the wires from the pot, and removing any obstacles that prevent rotating the pot, you should be able to unscrew it from the nut by turning the pot body. I'm not familiar with the SX-115 so I can't say if it is possible to do this on it. Holding the nut in place to install the new pot was nigh-on impossible until I cemented the nut to the wrench with two small daubs of rubber cement. It was easy to break the bond once the nut was threaded on. You'll probably have to loosen the nut and play around to where, when the pot is tight against the chassis, the terminals are pointed correctly. After it was done, I think it would have taken less time to remove the front panel (As long as you don't have to do any restringing).
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What have you tried in the way of cleaning the pot element? Fader Lube from the same people who make Deoxit is a good product for quieting noisy potentiometers. I think Don was asking what you had tried, if anything?
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Bob, AF6C
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Re: Audio Gain Pot-Replacement
George I would try penetrating oil spray from the dollar store.? It is usually found in the automotive department in a black and yellow spray can.? Much cheaper then what is usually suggested.? I don't think that the pot is actually sealed so spray where the terminals leave the cover and work the pot end to end several times.? This process is a bit messy so position a paper towel to catch the drips.?? This has always worked for me. Jim
Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
It is all "scratchy" and some breaking up of the audio when it is used.? I see no easy way to replace the think.? I just dont really feel like removing all the knobs, and the front panel to replace it.? Looking for some ideas, other then replacement!? Thanks-George KN3PAT
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Re: Audio Gain Pot-Replacement
Don:? You can assume anything you would like to!
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Re: Working on HT-32B & Weight Lifting
I too will die with mine too!!!!? Have the SX-115 my Dad gave me back in the '60's!? The HT-32B he gave me gave up years ago, and I didnt have the money to replace the transformer then.
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Now I have a HT-32B, HT-32A, SX101, and 2 SX-115's!? Love them al, and use them every day.? Check out my QRZ page!.? Putting a new audio gain pot in the SX-115!? It is a real back buster, and it is not as heavy as the 32's!!!!? George KN3PAT
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Re: Audio Gain Pot-Replacement
It is all "scratchy" and some breaking up of the audio when it is used.? I see no easy way to replace the think.? I just dont really feel like removing all the knobs, and the front panel to replace it.? Looking for some ideas, other then replacement!? Thanks-George KN3PAT
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Good stuff Walt - as usual. Thanks for doing this!
Tom W3TA
I have had several contacts for help with problems in the HA-1 T.O. KEYER in the past couple months. So, I wrote a test & repair guide for the HA-1. It is on my website, no cost download @
73
Walt Cates, WD0GOF
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A majority of acceptance is not proof of correctness.
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Don Buska - The Radio Lab Works
waltcates
Floyd - K8AC
Anthony W. DePrato
Jim Whartenby
don Root