[R-390] 1L6

David Wise [email protected]
Fri, 15 Aug 2003 13:38:38 -0700


Selenium rectifiers are known for increasing voltage
drop as they age.

If you wire in a 9V zener diode across the filament string
you can avoid the "replace bad tube =3D total burnout" scenario.
There's a really easy spot to do it; I can't remember the
details, but it involves the Line/Battery switch.  You'll
figure it out if you look under the chassis and study the
schematic.  The SS 1L6 replacement cannot be aligned on
the higher-frequency bands; too much Cin on the oscillator.

73,
Dave Wise

> -----Original Message-----
> From: Merle [mailto:[email protected]]
> Sent: Friday, August 15, 2003 1:31 PM
> To: [email protected]
> Subject: [R-390] 1L6
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> Hello to the list..
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> FWI  I have not had many problems with the famous 1L6 tube, I've
> restored several Trans-Oceanics over the years and found if the 1L6
> tested okay but would not come up and work for you. I would change the
> selenium rectifier to a 1N4007 diode and the slight increase=20
> in voltage
> would bring the set back to life! Also there is an article (=20
> not for the
> pure ones ) where you can construct a Solid State replacement for the
> 1L6 that will plug right in in place of the 1L6 makes sense to me !
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> 73
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> Merle
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