[Top] [All Lists]

Re: [Amps] Lube for roller inductor

To: <>, "Stan Gammons" <>
Subject: Re: [Amps] Lube for roller inductor
From: "Carl" <>
Date: Wed, 1 Aug 2018 20:41:41 -0400
List-post: <>
Aluminum for the coil??? I kind of doubt that but Ive been wrong a few times....... The Murch I remember only went to 80M also. Most tuners have insuffficient C to work well at 80/160 when those were the lowest frequencies they used and adding more L just let the smoke out faster.

When Stephen Elliot took over from his father he made several business changes, their coil wasnt all that good at high power and some loads anyway.

I dont even own a tuner and modify the amps as needed and/or play with the Smith Chart to come up with some length of coax, any impedance, to look good to the amp when added to the feed.

Ham since 1955

----- Original Message ----- From: "Stan Gammons" <>
To: "Carl" <>; <>
Sent: Wednesday, August 01, 2018 7:38 PM
Subject: Re: [Amps] Lube for roller inductor

Hi Carl,

I had taken the roller inductor out of the MFJ tuner to clean the roller since a couple of spots made a noticeable amount of static in the received signal when I tuned across those spots on the inductor. Perhaps too much power dumped in it from my L-4B :) When I took it out I noticed the rear Delrin plate had came back apart. It was broken when I got the tuner and I tried to repair it when regular epoxy. It held for a good while. This time I used some Loctite plastic bonder which will bond to Delrin if you rough the surface up with some 220 grit sand paper. After gluing the Delrin part and letting it cure for 24 hours, I reassembled the roller inductor. It feels different now and is easier to turn. If my Sencore LC75 is correct, the roller doesn't contact the coil in various places. So, I guess it's time get another roller inductor. Or use the Murch tuner I have. It has a beefy roller inductor in it. Looks like #8 aluminum. I don't think it will match as well as the T network used in the older MFJ-989C tuner though. The Murch tuner only has an 18 uh roller inductor too. The one in the MFJ is 30 uh.

I'm not sure when OEP quit making roller inductors. Seems like the email I got from Steven Elliot said around 20 years ago. I had sent an email and picture asking about the Delrin part because MFJ seem to think OEP made it, but Steven said that wasn't a part for the inductor they made. OEP still makes air variable caps.

Thanks for telling me about Cardwell Condenser. I didn't know anyone still made any of the E.F. Johnson stuff. May need some of that when I ever get around to building that GI-7B amp. Too many projects and too little time...



On 08/01/2018 05:01 PM, Carl wrote:
Stan, I wasnt aware that OEP quit production, I used to buy many some years ago.

Another place to check is Cardwell Condenser who is now part of Viking and they still make the old Johnson 229 series..


----- Or
iginal Message ----- From: Stan Gammons
To: Carl ;
Sent: Wednesday, August 01, 2018 3:38 PM
Subject: Re: [Amps] Lube for roller inductor

Hi Carl,

MFJ said they use SAF-T-EZE anti-seize.

Oren Elliot no longer makes roller inductors. They said they stopped selling them to MFJ around 20 years ago and MFJ makes their own roller inductors now.



On August 1, 2018 10:32:17 AM CDT, Carl <> wrote:
Why not contact MFJ who builds theirs as well as Oren Elliot Products plus Multi Tech Industries who builds "big" ones.Carl----- Original Message ----- From: "Stan Gammons" <>To: <>Sent: Sunday, July 29, 2018 11:29 PMSubject: Re: [Amps] Lube for roller inductor On 07/07/2018 01:05 PM, Bert wrote: I don't think Penetrox is a good idea for a roller inductor. As far as I know, Penetrox is only conductive if put under pressure. I would suggest one of the CAIG DeOxit products, e.g. DeOxit 5. Bert VE3NR Kind of reviving this thread since I have a roller inductor that was acting a bit flaky, so I took it out and gave it a good cleaning in my ultrasonic cleaner. No lubes left on it now and it's very clean. So, what is general consensus, DeOxit D5 is Ok to use to use on the roller? Unsure how much of a lubricant it is, but I know it's a great contact cleaner. 73 Stan KM4HQE Amps mailing list ---This email has been checked for viruses by AVG.

This email has been checked for viruses by AVG.

Amps mailing list

<Prev in Thread] Current Thread [Next in Thread>