[ARC5] Now I'm completely OT - re "rushing design into production"

Mon Nov 16 20:08:04 EST 2015

Is there anyone over 50 who did not own some model of the S-38 at some time 
or another?
Mike, W6MAB
-
-
----- Original Message ----- 
From: "Leslie Smith" <vk2bcu at operamail.com>
To: <arc5 at mailman.qth.net>
Sent: Monday, November 16, 2015 4:50 PM
Subject: [ARC5] Now I'm completely OT - re "rushing design into production"


> Richard (and others)
> You made the point that Mr. "Halli-craft" changed the design of sets
> rapidly, and perhaps without sufficient thought.
>
> Recently I listened to a historian contrast the manufacturing strategies
> used by Nazi Germany and the USSR as it applied to tanks/panzers.  His
> point:  the Russians thought through the full life-cycle of their T-34
> (and subsequent models).  The life of a T-34 was about 8 to 12 months,
> and everything was built according to that time frame.  The paint was
> rough, the castings were rough, everything was rough.
>
> The Russians stuck to their basic design - including a gear box that was
> so "stiff" a hammer lay on the floor between the driver's feet.  In
> contrast, the Germans constantly modified/improved their design -
> according to the demand of the Wehrmacht.  The result was that the
> Russian produced a huge number of their basic T-34, while the Germans
> produced small numbers of superb panzers.  The historian made the
> observation that the two contrasting strategies may have influenced the
> final result of the war - an interesting conclusion.
>
> My comment (above) came from Richard's comment - that he suspected
> "Hallicrafters rushed new designs into production too quickly to refine
> them probably."   In the context of the "command" sets, it's interesting
> (to me at least) to read about the delay between the presentation of the
> 'command' sets - some years before the first "decent" contract was let.
> It seems the "command/ARC-5" sets were subject to a LOT of preliminary
> assessment (as I would expect from any military organization).
>
> There are some interesting side-effects of this.  A communication system
> that provided a set or 3 radios in a rack, rather than one set with a
> band-switch.  A communication system that lasted for many years
> (although that may result from the pressure to not "rock the boat"
> during a war, rather than excellent design).
>
> As for me and the Hallicrafters "bottom of the line" S-38 sets - I
> deliberately chose the early model (with B.F.O.) because a B.F.O. is a
> distinct advantage (I think) over a regenerative I.F.   I want to
> compare the performance of the S-38 with the performance of the
> "command" series or receivers.  History (and technology) IS interesting!
>
> Thanks for your comment Richard!
>
> 73 de Les Smith
>  vk2bcu at operamail.com
>
> On Tue, Nov 17, 2015, at 06:12, Richard Knoppow wrote:
>>     My first receiver was an S-38B, I may still have it but can't find
>> it. It was surprizing on a decent antenna.  When we moved out to Los
>> Angeles, about 1950, 10 meters was a an unprecedented peak. The S-38
>> could hear signals from all over on a 40 meter folded dipole.  I could
>> read SSB with care but the lack of an RF gain control made more
>> difference than lack of selectivity or stability.
>>      The odd Hallicrafters arrangement for the BFO in this receiver is
>> to make the IF stage regenerative just at the point of oscillation. That
>> also makes it more selective. A resistor is switched in to reduce the IF
>> gain when the switch is set to CW, which helps because the regeneration
>> also increases the gain of the IF stage. A clever idea that sort of
>> works. The original S-38 had a real BFO and the extera tube also had a
>> diode in it so there was also a noise limiter.  The design change saved
>> a tube and some components but lost the noise limiter and ability to
>> shift the BFO frequency, the latter of not much value considering the
>> broad response.
>>      I have a suspicion BTW that Hallicrafters rushed new designs into
>> production too quickly to refine them properly.   If I am right it would
>> explain the plethora of variations of models as ideas for either
>> reducing production cost or improving performance came up. Hallicrafters
>> was not the only company to make changes during production but perhaps
>> made more than usual.
>>
>> On 11/16/2015 10:26 AM, Kenneth G. Gordon wrote:
>> > On 16 Nov 2015 at 10:16, D C _Mac_ Macdonald wrote:
>> >
>> >> My first receiver (and transmitter) was the Walter Ashe $49.50 Novice
>> >> Station with 6SN7GT regen receiver.  Worked a lot better than the S-38 
>> >> I
>> >> borrowed when the 6SN7GT went dead and I couldn't afford a replacement
>> >> tube.
>> > My first "good" receiver was a Hallicrafters S-41G which a plumber
>> > sub-contractor for my step-father's construction company found in his
>> > basement after he moved into the house. At least the BFO in that thing
>> > worked....
>> >
>> > I bought an S-41G somewhat recently, mainly just to see how it worked 
>> > when
>> > compared with my more modern rigs. I almost can't figure out how we 
>> > ever
>> > used those things to make as many contacts as we did. Yet I even worked
>> > DX
>> > on 20 meters using the S-41G back then. The entire 20 meter band is not
>> > quite 3/16" wide on the dial. Calibration was literally non-existent.
>> >
>> > I suppose the extremely poor selectivity of those sorts of receivers is
>> > the primary reason I preferred to operate CW, and still do. The AM
>> > portions of the bands were simply one huge collection of heterodynes. I
>> > couldn't stand to listen to that crap for more than a few minutes.
>> >
>> >> My ears aren't as good as they once were, but newbies still can't 
>> >> figure
>> >> out how I can pick signals out during Field Day!
>> > Yes. I have had the same experience. My "wet filter" has a bandwidth of 
>> > 50
>> > Hz. It works just fine, thank you, even after all these years. I find
>> > narrow bandwidths in modern receivers disconcerting: I can't tell what
>> > else is going on on the band, and it bothers me. Besides, I also don't
>> > like the sound of a restricted bandwidth. There are times, of course, 
>> > when
>> > very narrow (400Hz or so) bandwidths are useful...
>> >
>> >> There's still nothing that compares with trying to copy either ICW or
>> >> voice signals under crowded conditions to improve operator skill.
>> > Indeed, yes.
>> >
>> > I think Glen's idea of requiring new hams to spend at least 2 years 
>> > using
>> > wide bandwidth and unstable receivers is excellent, although impossible 
>> > to
>> > implement. Sadly.
>> >
>> > Ken W7EKB
>> >
>> > ______________________________________________________________
>> > ARC5 mailing list
>> > Home: http://mailman.qth.net/mailman/listinfo/arc5
>> > Help: http://mailman.qth.net/mmfaq.htm
>> > Post: mailto:ARC5 at mailman.qth.net
>> >
>> > This list hosted by: http://www.qsl.net
>> > Please help support this email list: http://www.qsl.net/donate.html
>> >
>>
>> -- 
>> Richard Knoppow
>> 1oldlens1 at ix.netcom.com
>> WB6KBL
>>
>> ______________________________________________________________
>> ARC5 mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/arc5
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:ARC5 at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>
> -- 
> http://www.fastmail.com - Email service worth paying for. Try it for free
>
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html 


---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus