Hi Carol,
Thanks for the reply.
I know of the G3LLL processor from reading the FT newsletters, too. It WAS
in the circuit during receive, as well as transmit. In some of the
comparisons, this was the deciding factor that gave the G3LLL processor an
edge over the Yaesu's. So you are correct regarding the 2.4 KHz filter being
in line during receive.
The Yaesu version uses the switching polarity of the RF PROC switch which is
LOW during receive, and HI during transmit, to route the IF through the
limiter/filter section of the board when ON; and around that part of the
circuit when OFF.
Regarding AM use, I thought it might give a boost to the audio, kind of like
using an amplified microphone. But it must not work that way at IF the way
it does when amplifying at AF.
Agreed on cost of 6JS6C! I have a couple spare sets, but I am babying my
1977 vintage tubes along. They still do about 150 watts.
I don't think it is the efficiency of SSB, but just the normal
characteristics of human speech, that makes a processor valuable, It helps
to boost the low amplitude level characteristics of the soft sounds, i.e.
th's and sh's, etc. and limits the peaks of the loud or hard sounds to
eliminate overdrive that leads to spurious and harmonics. Therefore, the
AVERAGE is greater, but the PEAKS are limited.
73,
Rick, WD8JJA
----- Original Message -----
From: "Carol L Maher" <w4clm.ham@juno.com>
To: <WD8JJA@arrl.net>
Cc: <yaesu@contesting.com>
Sent: Tuesday, May 20, 2003 5:23 PM
Subject: Re: FT-101E Speech Processor
> Davis_R" <WD8JJA@arrl.net> writes:
> So it seems. Do you know why or how it doesn't do anything on AM? I
> have
> looked pretty hard at the schematic, and for the life of me, I can't
> figure
> out how it gets disabled in the AM mode
> -------------
>
> Hi Rick,
> I don't know what to tell you there, it would take your sitting down
> with some colored pencils and tracing the I.F. signal flow through the
> rig both in and out of the entier I.F. chain and into the speech
> processor
> on paper to find out how the processor is out of circuit during AM
> operation.
> (more on that in a moment)
>
> Now that you bring it up. Here's an interesting tid bit for you.
> I have a really nice FT-101EE.... someone installed a third party
> speech processor into the unit apparently years ago. As you are
> more then likely are aware. The EE model did not come with the
> processor.
> The speech process that was installed into my EE was made by
> Harry Lemming G3LLL (in the UK.)
> The G3LLL processor when turned on gives a considerable boost to the
> RECEIVER I.F. signal too......
> Yup, that's what I said, the receiver signal is boosted.
> My signals on SSB come up considerably when the processor is turned on
> using SSB mode. So go figure !! However it's a known fact that the
> G3LLL
> processor will do this. I read about it in some early Fox Tango
> bulletins
> from the mid 1970's other people received the same benefits using the
> G3LLL
> processor board.
>
> I'm in touch with Harry once in a while by E-mail and next time I talk to
> him
> I will ask him why this is. The Yaesu processor boards are only in
> circuit during
> transmitt mode when using SSB.
>
> Now that I think about it, here in part could be part of the reason Yaesu
> did this.
> If that 2.7 Kc (What ever it is-XF-32A) filter is in the I.F. during
> receive mode.
> The it could possibly present a problem of being too narrow a filter when
>
> switching over to AM mode. Now more then likely you would never turn on
> the processor in AM anyway, but just for giggles I turned my G3LLL
> processor
> on to see what it would do to the receive signal while I was listening to
> 10 meter AM.
> It was pretty darn narrow and completely defeated the purpose of having
> had the AM filter installed in the rig in the first palce. Effectively I
> would have
> been putting an 8 pole SSB filter in my I.F. during AM operation, there
> by
> narrowing down the I.F. does that all make sence to you?
> I thnink it does to me.....hee hee....
>
> Anyway no real benefits to running a processin in AM mode anyway.
> Keep in mind, you need to keep the I.C. plate current down to something
> like 150 MA when using AM mode.
> It's very important you do this. Running the rig at something like 20 or
> 25
> watts output at the very most. If you run it any harder you will be
> buying yourself
> a new set of 6JS6C finals and they don't come cheap these days.
> To be completely honest with you, I don't know all the engineering behind
> the
> speech processing. I have read up on it a bit, but I really need to look
> at the
> text again before I can speek on the subject with any confidence.
>
> In my simple lay man's terms, as far as I know there would never be any
> benefit running the processor in AM because you already
> have a carrier present which then becomes amplitude modulated increasing
> the
> amplitude of the carrier to it's Peak to Peak value. I can only assume
> that
> SSB mode the mode is not 100% efficient, such is the case with anything
> in this life. (RF amplifiers included)
> So the speech processor attempts to bring the SSB signal back to it's
> AM equivilent of what you would see had you been running AM or CW
> at full power of say 100 watts, there by filling in the valleys inbetween
> your syllables when speeking on SSB voice mode.
>
> It is again important to remember that you are running SSB, the 6JS6C
> tubes
> can take this because they are not running at a CONTINIOUS DUTY CYCLE
> ON SSB. Once you go to AM, you are running continously and it's rough
> on those tubes. So the RF speech processor will bring up the average
> signal
> being produced and you will see an increas in your output as well as an
> increase in current as shown on the current meter (I.C. position) but you
> will
> never reach the same level of continous output that you would reach power
> wise, say if you were running 150 watts keyed down in C.W.
>
> I hope this makes some sence here because I'm rambling on some.
> Sorry.
> Maybe another contributor to the forum can enlighten us on the finer
> points of speech processing. I think I'm close with my understanding,
> but I'm no electrical engineeer.
>
> Stay and touch and feel free to write again anytime.
> Regards
> Carol Maher
> W4CLM
>
>
>
> .
>
> ----- Original Message -----
> From: "Carol L Maher" <w4clm.ham@juno.com>
> To: <WD8JJA@arrl.net>
> Sent: Tuesday, May 20, 2003 2:08 PM
> Subject: Re: FT-101E Speech Processor
>
> > Won't do a thing that I know of on AM Rick.
> > Regards
> > Carol
> >
> >
> > On Tue, 20 May 2003 11:12:35 -0500 "Davis_R" <WD8JJA@arrl.net> writes:
> > > Hi Carol. Thanks for the reply.
> > >
> > > To be honest, I listen more than transmit. But from what I can tell
> > > from
> > > the few signal reports and a limited number of on-the-air
> > > experiments, I
> > > think it does the job well. I QSOed with one guy that said on/off
> > > didn't
> > > make any difference. I was an S-9 to him. When we finished, another
> > > in
> > > Texas said I was S-4 and came up about one S unit and the audio was
> > > louder.
> > > I don't know if there is any reason to turn it OFF in SSB. Of course
> > > it
> > > needs to be off for PSK31, SSTV, etc. I don't know if it works at
> > > all on
> > > AM.
> > >
> > > 73 and God Bless.
> > > Rick, WD8JJA.
> > >
> > > ----- Original Message -----
> > > From: "Carol L Maher" <w4clm.ham@juno.com>
> > > To: <wd8jja@arrl.net>
> > > Cc: <yaesu@contesting.com>
> > > Sent: Sunday, May 18, 2003 4:42 PM
> > > Subject: FT-101E Speech Processor
> > >
> > >
> > > > Rick, your processor sounds to me like it's operating properly.
> > > > How's it working out for you now that you have had a chance to
> > > run it a
> > > > while?
> > > > Regards
> > > > Carol
> > > > W4CLM
> > > >
> > >
> > >
> >
>
>
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