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THE AM BULLETIN BOARD => Technical Forum => Topic started by: KD5KC on May 13, 2019, 09:57:41 PM



Title: Restoring a clean FT-101E. Decisions about final tubes.
Post by: KD5KC on May 13, 2019, 09:57:41 PM
Good evening all.

I pop in here to read a little from time to time.  I run the power grid locally, in 12-hour shifts, and the long quiet nights leave time for researching stuff.  But I've had very little luck in my present quest.

A very clean FT-101E is almost complete - so far.  All new caps everywhere.  Getting ready for final alignment and check-out and the 6JS6C tubes seem soft.  I have a few 12BY7s for driver, but it seems OK.  I do not have the Japanese 6JS6Cs.  And it seems like the available 6JS6Cs are not Jamanese and are not compatible without mods.  OK.

While investigating that, I ran across a suggestion to convert to 6146s.  And I immediately thought of you good folks.  What mode would best benefit from a tube upgrade like that than the AM guys I said.  I've tried searching with several key phrases here, but so far found nothing.

Has anyone here done the 6146 mod to an FT-101 series?  What version 6146?  Any key points of gotchas to watch out for?

Thanks Much.  And if you're on the western grid, I'll do my very best to keep the 60 Hz steady all night.

Mike- KD5KC.


Title: Re: Restoring a clean FT-101E. Decisions about final tubes.
Post by: Detroit47 on May 13, 2019, 10:46:37 PM
Ask the Fox Tango guys.

http://foxtango.org/ft101/foxtangoft101.htm


Title: Re: Restoring a clean FT-101E. Decisions about final tubes.
Post by: KK4YY on May 14, 2019, 06:49:54 AM
How soft is soft? How much output power do they produce? Can you measure it accurately?

Don


Title: Re: Restoring a clean FT-101E. Decisions about final tubes.
Post by: WA2SQQ on May 14, 2019, 09:27:18 AM
https://www.youtube.com/watch?v=YRgux8WH4RU

I suggest you watch Buddy's video on this topic. He mentions the difference between the Japanese vs. the US versions of these tubes. He also has a vew other videos on the FT101 that you might find interesting.

Keep us posted


Title: Re: Restoring a clean FT-101E. Decisions about final tubes.
Post by: W1NB on May 14, 2019, 06:22:15 PM
The only modification to run non-Toshiba 6JS6 finals is swapping the fixed capacitor in the neutralization circuit. That’s a whole lot easier than changing the finals to 6146s. I’ve repaired and restored 101s since the late 70s and used RCAs, Sylvanias and others with no issues once the cap has been replaced and the rig properly neutralized.


Title: Re: Restoring a clean FT-101E. Decisions about final tubes.
Post by: KL7OF on May 19, 2019, 04:46:33 PM
The ft 101 power transformer doesn't have enough scrote to run 6146s
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