It may be silver plated copper wound on a ceramic form. It's all nice and shiny
though. Silver will tarnish over time. I'd think it would be black like the
coil in my L-4B. I about have to use a tuner since I don't have the room for a
full length 80/75 meter antenna.
Yes, the Murch I have only goes to 80 meters.
73
Stan
KM4HQE
On August 1, 2018 7:41:41 PM CDT, Carl <km1h@jeremy.qozzy.com> wrote:
>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.
>
>Carl
>Ham since 1955
>
>
>
>----- Original Message -----
>From: "Stan Gammons" <s_gammons@charter.net>
>To: "Carl" <km1h@jeremy.qozzy.com>; <amps@contesting.com>
>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...
>>
>>
>> 73
>>
>> Stan
>> KM4HQE
>>
>>
>> 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..
>>>
>>> Carl
>>>
>>>
>>>
>>> ----- Or
>>> iginal Message ----- From: Stan Gammons
>>> To: Carl ; amps@contesting.com
>>> 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.
>>>
>>>
>>> 73
>>>
>>> Stan
>>> KM4HQE
>>>
>>>
>>>
>>> On August 1, 2018 10:32:17 AM CDT, Carl <km1h@jeremy.qozzy.com>
>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" <s_gammons@charter.net>To:
>>> <amps@contesting.com>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 Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps ---This email has
>been
>>> checked for viruses by AVG.https://www.avg.com
>>>
>>> ---
>>> This email has been checked for viruses by AVG.
>>> https://www.avg.com
>>>
>>
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