[Hallicrafters] SX-96? (SX-88)

[Carl]

----- Original Message ----- 
From: "Mike Everette" <radiocompass at yahoo.com>
To: <WA1KBQ at aol.com>; <wq9e at dtnspeed.net>; "Carl" <km1h at jeremy.mv.com>
Cc: <macklinbob at msn.com>; <Hallicrafters at mailman.qth.net>
Sent: Sunday, August 17, 2008 9:45 PM
Subject: Re: [Hallicrafters] SX-96? (SX-88)


>
>
>>
>> IOW they were the first truly new design since the SX-9.
>>
>> Carl
>> KM1H
>>
>
> You're real close to right.
>
> Probably the SX-71 was the first "truly new design" as it predates the 
> SX-88 by four or five years (1949? 1950?).

1949. And I included it earlier, just didnt give it the proper respect 
as the innovator.


>
> The "lineage" of Halli designs is interesting, to say the least.  The 
> SX-16 begat the SX-24 which begat the SX-99 which begat the SX-110. 
> It may go further forward and backward.

There isnt much difference between the SX-9 and the rest of the silver 
dial line. An extra tube or three and a few minor additions. The SX-9 is 
a S-20R/S40 without the xtal filter. Performance didnt improve over the 
years either, mine all sit on shelves.


  The S-20R begat the S-40 which begat the S-85 which begat the S-108, 
etc.  The S-19 did not beget the S-38; rather, it begat the S-53A which 
begat the S-107.  Very clever.  (The original S-53 was an exception, 
because it had the high frequency IF.)


The Echophone EC-1 begat the S-38.


>
> If you look closely at the ad copy for the spreads on the S-40, from 
> 1946, you'll notice how all the emphasis is on the styling.  Not a 
> word about the circuitry being the same as the S-20R, except for a 
> couple of tube updates (nothing substantive; sub a 6J5 for a 76 etc). 
> Makes one wonder how many bought a "brand new post-war" S-40 to 
> replace an S-20R... hmm.


Every kid whose parents thought he needed the latest and greatest within 
their budget. I still pity the kids who got stuck with S-38xxx's. Many 
of my HS friends never got past their Novice due to them and the S-53A. 
After the SX-25 disaster I got a used HQ-129X and found the world of 
chasing DX. I was 16 at the time.



>
> If you take a Sams for the SX-99 and compare it to the SX-110, there 
> is NO difference in the circuitry or in the underchassis component 
> layout.  The only differences are purely mechanical, to allow for the 
> differences in the dial mechanisms.
>
> Probably the main reason Hallicrafters went belly-up was because no 
> one could figure out how to successfully solid-state the old designs!


Good point. The FPM-300 certainly was no gem but neither was anyone 
elses SS attempts back then. Even the HRO-500 is a dog on a good 
antenna.


>
> The SX-96's main circuit difference from the S-76 is, of course, 
> "selectable sideband."  All that is, is a crystal controlled second 
> conversion oscillator which can be selected to run on the high side or 
> low side of the 1650 KHz first IF.  The S-76 uses a free running 
> oscillator.  And, the SX-96 has a stronger BFO plus improved detector 
> and AVC to allow AVC and S-meter function on CW and SSB modes.
>

One that intrigues me is the SX-140 given to me which is the only SX 
without a xtal filter. Ive added a second conversion down to 262 Kc and 
use 2 stages of IF with old auto radio transformers. Got rid of that 
pathetic regen IF entirely and the BFO is free running at 262Kc
Its now very nice on AM, passable on CW, quite stable due to the very 
low B+ they used and acceptably sensitive thru 10M. The noise limiter is 
very good.

It came with a Knight T-150A which just needed a cleaning, some tubes 
and audio mods.

They both now live at our cottage in Maine and its a lot easier than 
lugging the real boatanchors back and forth.

Carl
KM1H



> 73
>
> Mike
> WA4DLF
>
>
>
> ______________________________________________________________
>