[Boatanchors] Subject: SSB Generation - Phasing VS Filter Opinion - HT-32A/B vs HT-37 Example

[Whitebear1122]

Hi Doug, Many thanks for your opinions and insight into phasing.  As a newbie I was looking at the simplicity of the filter method.  That’s part of the reason for pinging this group, to gain insight into the reasons one would pick filter over phase.  

It was interesting that the other respondents also cited the high quality HT-37 audio compared to the HT-32 filter audio.  

My Don Stoner SSB Handbook has a schematic of the Central Electronics 20V and a big discussion of phasing.  I’m going to start reading that in great detail now that you guys have pointed out a good reason for phase SSB generation.

More questions to come :)

Many thanks, 73, Scott WA9WFA
  

> On Jul 19, 2019, at 11:35 AM, Doug Hensley <w5jv at hotmail.com> wrote:
> 
> A long time ago during the heavy entrance of hams into SSB,  I remember that
> the HT-37 had a reputation for exceptional audio quality which was not heard in the
> more expensive HT-32A/B rigs.  The HT-37 audio was so enjoyable that it stood out causing
> ham after ham to respond: "boy you sound good.  What kind of rig is that?".  We were
> all evaluating SSB rigs during this period and pretended to listen to "sound quality"
> as if we knew what we were doing.
> 
> Well, the applauded rig, the HT-37, was a manually adjusted phasing rig as opposed to
> the no tune/no adjust crystal filter units.   I used mine with both an EV 729SR, a little
> dark gray, flat face ceramic with a rocker switch and an EV-674 which looked great
> but not sure if there was much improvement.  Both were cardioid mics.  In on the air
> tests I remember the general audio stood out over and above the peculiarities of a
> different microphone (within reason of course) and frequently one just sounded
> different without degrading the audio.
> 
> Before "CQ", we would turn the power way down, un-mute the receiver and listen to
> ourselves in headphones saying 'test 1 2 3 ....' as we phased out any discernible carrier.
> Can't explain why, and certainly have no technical reason for it, but I miss that kind of
> up front and personal interaction with my transmitter today.
> 
> The point is that there are other considerations in the trade off between constructing
> the crystal filter generator versus the balanced side-band phasing generator.  In the end,
> the crystal filter method usually wins out because of its easier construction and the fact
> that it fixes carrier suppression so that there is no need for adjustment during operation.
> The audio quality is never a consideration and that argument is moved to an endless string
> of conversations on mike quality, audio eq's & pre's, etc etc.
> 
> My 2 cents.  Hope this adds some flavor to the ideas you are thinking through.  Forgive
> any glaring mistakes or blunders here.  Just passing on what my memory recalls.
> 
> Cheers,
> 
> Doug W5JV
> 
>