[Hallicrafters] Hallicrafters HT-32B ON THE AIR

[Al Parker]

Hi Jim, Lee, et al,
	IIRC from old info from un-remembered sources, the main reason Halli 
brought out the HT-37 was to reduce costs, both to the mfgr and to the 
customer.  I'm sure the phasing SB generator was cheaper to mfgr than 
the filter type, filters replaced by diodes, resistors, etc.  Plus the 
cheapened the panel & case, plus??.
	One thing that seems to have been a problem with the HT-32 is that they 
are very easy to overdrive with audio, and thus produce very wide 
splatter.  Can't remember if the HT-37 has the same problem, but 
probably.  Lee said he turned the mic gain down to 2 and thought it was 
better.  I had the same problem with my HT-32, don't remember what I 
used to set the gain to, but it was very low, with an unamplified mic 
(Astatic 10-D).  Occasionally I'd get complaints, but usually cuz the 
gain was up a bit.
	I installed a published AGC mod to the rig abt 2 yrs ago (don't 
remember now the source, but will gladly dig it up and fwd to anyone 
concerned), and now run the gain at 4, with no (more) complaints from 
nearby adjacent net folks on crowded 20m on Sun. PM's.
	All said, I don't know what the specs were, but if anyone has info, pse 
share it with us all.
73,

Al, W8UT
www.boatanchors.org
www.hammarlund.info

"There is nothing -- absolutely nothing -- half so much
worth doing as simply messing about in boats"
Ratty, to Mole

On 2/20/2015 11:23 AM, Jim Liles wrote:
> Hi Lee,
>
> Check 7-16.3.  It indicates 650 cycles to 3000 cycles @3db --- say nothing about shape factor.  Describes how to adjust the center point as well.  Don’t know what the shape factor for the 9Mc filters was at the time.  Anyone know how many poles were in the filter
>
> That begs a question.  Why did they change their strategy to phasing in the HT37 rather than crystal.  The phasing system has by design, broader skirts than crystal.  Maybe they had a problem with the 9 Mc filters of the day.  Might be interesting th try a modern 9Mc crystal filter.
>
> Anyone have internal correspondence with the Hal guys or design notes regarding the Ht-32B?
>
> Kindest regards Jim K9AXN
>
> -----Original Message-----
> From: Lee via Hallicrafters

> Hi everyone,
> Well, the Halli HT-32B is on the air. After many years of sleeping.
> Changed the Electrolytics, 3 Black Beauty's. and the Bias diode (was selenium).
> Also, someone before me had already SS the HV and B+.
> Also had to adj. the carrier balance.
>
> Working pretty darn good and WOW it is easy to tune-up.
>
> One issue has surfaced...last night I was on 7139 LSB of course...and a guy came on and said I was 20 over on 7142 (above my freq)
> I had several look at my signal and said it looked OK. But one had a Flex 1500 and helped me out. He said I was about 5KC wide and my signal went away at 7141.5 and went away at 7135.5.
>
> I turned the Mic gain down some (to 2.0) and he said it was a little better but still pretty wide.
> Today I had a couple guys on 7131 check it out as well and 4 KC was the width....I do realize these old crystal filters did not have straight skirts.
>
> What should be expected on this TX as far as bandwidth and interference to neighbors??
> What has other experienced?
> 73,
> Lee, KC9CDT
>
  <snip>