[Hallicrafters] sx101 subchassis

[Jim Liles]

Hi Mark, Glenn:

The Hallicrafters schematics  of that era seemed to call things paper that 
were Ceramic or Film caps.  Hallicrafters was not the only manufacturer that 
grossly mislabeled components in the transition from paper to Ceramic and 
Film caps.

If you have ever had a sub-chassis apart, six paper caps would not have fit 
in the confined space of the Sub-chassis.  I have had them out of the Mark 
1A many times and never found paper.  After finding no paper numerous times, 
I simply test components from tube pins and edge lines and do not remove 
unless it fails or a resistor tests out of tolerance.

The SX-101 Mark1  calls out Ceramic 1957-58

The SX-100 Mark1A calls out Ceramic  1956-61

The SX-96 calls out Ceramic 1955-56

The S76 1950-55      calls out and used paper but there are but TWO rather 
than SIX caps in the Sub-chassis.  Look at the S76 sub-chassis and you will 
see that two fit but six would be very very difficult.

Never say never.  I guess there may have been some midget paper caps built 
that might have fit but do not believe it to be so and have never heard of 
paper caps in the sub-chassis of any but the S76.

NOTE:  Different issue but worth attention.  The caps used on the BAND WIDTH 
switch are called paper and were paper until later products, which used Film 
i.e. the SX-117 and SX-115.  All should be replaced with Film caps not 
Ceramic if you expect the filter to work properly.  The original paper caps 
were more stable and predictable than Ceramic caps.  Hallicrafters never 
used Ceramic caps on any of the 50Kc Band width switches.  Early radios 
paper and later, Film --- no Ceramic.

A super day to you Mark and Glenn, enjoy that radio.

Kindest regards Jim K9AXN



-----Original Message----- 
From: Mark K3MSB
Sent: Sunday, January 13, 2013 2:35 PM
To: Nash4447 at cs.com
Cc: hallicrafters at mailman.qth.net
Subject: Re: [Hallicrafters] sx101 subchassis

Hi Glenn --

There are paper caps on some model runs.

The parts list in my manual indicates paper caps, but when I removed the
subchadsis I didn't find any.  Of course, my manual was a photocopy from
somewhere and didn't go with the receiver.

73 Mark K3MSB

On Sun, Jan 13, 2013 at 12:23 PM, <Nash4447 at cs.com> wrote:

>
> Just FYI since we are talking about subchassis parts.   A couple years ago
> I restored a SX101 that was dead on the higher bands.  I bit the bullet 
> and
> removed the subchassis and found two things - there are no paper caps 
> under
> the subchassis on the 101s  BUT I found that the resistor feeding the 
> plate
> voltage to 2nd osc, I think something like a 12AU7, was sky high in value,
> hence little or no B+ on the tube.
> Replacing that  resistor  with a 1 watt variety brought things back to
> life.
>
> Something for the memory banks
>
>
> Glenn    K6PZT