Hi Steve,
The problem with the monitor circuit is that even when its done at
RF, its usually done in one of the low level IF stage. This lets you
hear what the speech processing sounds like, but doesn't help if
your problem is downstream (like in the PA). In the case of the
TS-950SDX I was using a few weekends ago, the monitor gave
a false alarm as the distortion was due to external RF getting into
the monitor circuit. The actual RF output was clean as evidenced
by the received signal on an external receiver (TS-940S).
You rule about using a zero signal background reading is a
good one, although those with loud blowers might disagree.
On that same TS-950 mentioned above, I had a hew hundred
watts of 60 Hz hum initially. This was tracked down to the
single operator 2 radio (SO2R) switch box. The box switches
both the mic and shield connections from each rig in order to
minimize hum pickup. Unfortunately, the input jacks were
very close together and I had used 1/8" phone plugs with
metal sleeves. A 1" long piece of electrical tape placed over the
metal sleeve of the offending phone plugs eliminated the hum completely.
73 de Mike, W4EF.............
----- Original Message -----
From: "Steve Katz" <stevek@jmr.com>
To: "'Mike'" <W4EF@dellroy.com>; <amps@contesting.com>; "John T. M. Lyles"
<jtml@lanl.gov>
Sent: Tuesday, March 12, 2002 1:31 PM
Subject: RE: [Amps] 10 Meters
> Since we're venting...
>
> -Most all modern rigs, at least all the "high end" ones, have a MONITOR
> function that allows you to hear what you sound like, on the air. It's
not
> just tapped into the audio modulation channel, in most decent rigs the
MONI
> is a sampling of the RF envelope post modulation, and demodulated by
product
> detection. It works.
>
> -Besides using that obvious feature, I have a golden rule: When using a
> 1500W (or more likely 2500W full-scale) Wattmeter in line, the meter
> indication between words should fall to "zero." Any indication whatever
is
> an absolute sign of having nearly zero signal-to-noise ratio on the
> transmitted signal, and what will sound like maybe 3dB of carrier
> suppression.
>
> -And why, oh why, do DX stations who can barely speak English use
phonetics
> they cannot pronounce? It's really funny. The French stations who use
> "Florida," a word that is nearly impossible to pronounce for them, instead
> of "France," which ought to be an easy one.
>
> -And on and on it goes...
>
> WB2WIK/6
>
> "Each success only buys an admission ticket to a more difficult
problem." --
> Henry Kissinger
>
> > -----Original Message-----
> > From: Mike [SMTP:W4EF@dellroy.com]
> > Sent: Tuesday, March 12, 2002 12:54 PM
> > To: amps@contesting.com; John T. M. Lyles
> > Subject: Re: [Amps] 10 Meters
> >
> > Hi John,
> >
> > I operated the contest two weekends ago. I had a two
> > radio setup so I actually listened to my own signal a few
> > times. I was concerned because my monitor output sounded
> > kind of crappy on 10 meters (like I had RF in my audio), but
> > when I listened to the end-to-end over the air signal it sounded
> > pretty good. Anyone with a single-op two-radio setup (SO2R),
> > which is very common in contesting these days, should be able
> > to do this sort of test without even slowing down. Likewise
> > multiops typically have at least one spare rig for multiplier
> > spotting, so they too should be able to spot check their TX
> > quality. Nevertheless, I heard a lot of garbage out there. Many
> > signals were so overprocessed that they actually reduced
> > intelligibility.
> >
> > From what I understand, the ARRL OO's were out in force
> > reminding people of where the band edges are located.
> > Perhaps they could also start serving notice on those people
> > with 80 grit audio.
> >
> > 73 de Mike, W4EF.....................
> >
> >
> > ----- Original Message -----
> > From: "John T. M. Lyles" <jtml@lanl.gov>
> > To: <amps@contesting.com>
> > Sent: Tuesday, March 12, 2002 11:51 AM
> > Subject: [Amps] 10 Meters
> >
> >
> > > I was mobile QRP (5 watts) this past weekend, while crossing USA in
> > > automobile. 10 meters was hot, lotta DX.
> > > I was was surprised by a number of sounding stations. A lot of high
> > > powered stations in Europe, Asia and Carribean were overdriven
> > > (obviously amplified) and had their audio so compressed and
> > > overloaded that it was painful to hear. I suppose that they believe
> > > that they have what it takes to crack through the QRM. It was hard
> > > to hear stateside transmissions, but I noted that they also tended to
> > > the same extreme. There WERE some nice sounding transmissions, mostly
> > > casual QSOs between hams that didn't last only 10 seconds (just long
> > > enough for a 'five by nine' report). I don't mean to poo poo contests
> > > and DX chasing, but the sound of some is less than desirable.
> > >
> > > There was also a lot of tuner-uppers (carriers, high speed dits, and
> > > whistles and hellos) on the band, who don't know to use a dummy load
> > > and completely obliterate someones QSO. Since I had little to compete
> > > with, I stayed away from pileups, have to say that I mostly turned
> > > off the radio in disgust, with the sheer quantity of LIDs who stomp
> > > on others. But then again, only the worse and loudest were noteworthy
> > > to be mentioned here, and there were plenty of nice sounding stations
> > > as well. Since this is the contesting list, I am 'venting' here. No
> > > one on this list would sound like that, right?
> > >
> > > --
> > > _______________________________________________
> > > Amps mailing list
> > > Amps@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/amps
> > >
> >
> >
> >
> > _______________________________________________
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