[Hallicrafters] S20-R band 4 LO warble

[James Liles]

Hi Richard and Paul:

The 6K8 LO in the S20-R, SX24, and SX-25 create a ratty note or for lack of 
a better word Warble on band 4.  A spectrum analyzer shot of the oscillator 
on band 4 looks like a jagged waterfall kinda like a bunch of gerbils 
running in a treadmill with the a bunch of marbles on a tin barn roof!!!  It 
is not a result of physical movement or jarring.  The output is pristine on 
the other bands.  Don`t want to make major mods --- It`s my original 
receiver --- maybe just a change of the 6K8 to something else.

Kindest regards Jim K9AXN




-----Original Message----- 
From: Paul Daulton
Sent: Tuesday, July 26, 2011 5:09 PM
To: james.liles at comcast.net
Subject: Re: [Hallicrafters] S20-R band 4 LO warble

My memories of SX24 and 25 from High School days that was cured by a
new 6k8 mixer. S 40 used a different tube for the first mixer.

Paul k5wms

Quoting James Liles <james.liles at comcast.net>:
> Do the S-40 or S-40A receivers have the warble on band 4 caused by LO 
> volatility
> like the S-20r, SX-24 and SX-25?  At what level of receiver was the LO 
> problem
> corrected???
>
> Kindest regards Jim K9AXN