Richard and Don --
My 570D(G) is now going on three years old. I've always noticed that
there's a very noticeable difference between using the stock 2.4 khz filter
on LSB/AFSK with the 300 hz DSP digital audio filter, and the 500 hz IF
filter in FSK mode. The skirts and bandwidth seem much tighter on FSK, and
when tuning CW signals in the FSK position to compare with the CW position
at 500 hz, I really can't tell any difference. I've also tried this using
Spectrogram. That has always convinced me that the filter is really there
and working as it's supposed to in FSK. I have also tried fooling the 570
into using the 500hz filter in SSB by telling the menu selection that it's a
1.8 khz. That works, but my personal preference is always for FSK.
The biggest problem I've had with the 570 isn't the selectivity per se, but
the lack of an AGC off position. For that reason I tend to favor my 850
with 500 hz filters in both IFs under contest conditions. There's a fix for
this at the designer's own website, at http://www11.cds.ne.jp/~cqdx/ if
you're more adventurous than I am at the moment.
Jon K1US
----- Original Message -----
From: "Smith, Richard" <RSmith@palmerdodge.com>
To: "'Don Hill'" <aa5au@msn.com>; "WriteLog Reflector"
<Writelog@contesting.com>; "WF1B Reflector" <wf1b-rtty@wf1b.com>
Sent: Tuesday, October 10, 2000 7:45 PM
Subject: RE: [WriteLog] Re: Kenwood TS570D
>
> I have also used the TS-570D for RTTY work with good results. But, I
think
> you are being fooled by the 250 Hz. IF filter. I have used the rig with
the
> 500 Hz IF filter, and have never been convinced that it is actually being
> used in the FSK filter mode. Rather, I think that even if you select the
> 300 Hz. filter from the Digital Filter menu, all you get is the 2.4 kHz.
SSB
> IF filter and a 300 Hz. digital audio filter. The AGC responds to
> everything in the 2.4 kHz. IF passband, making the filter seem much wider
> than the expected 300 Hz. I would expect that the narrower IF filter,
> whether 500 Hz. or 250 Hz. would be brought into action when the narrow
> Digital Filter mode is selected, but I don't think it is. It appears that
> the narrow IF filter is only used in the CW mode.
>
> 73, Rich W1EZ
>
> > -----Original Message-----
> > From: Don Hill [SMTP:aa5au@msn.com]
> > Sent: Friday, September 29, 2000 11:29 PM
> > To: Don Hill; WriteLog Reflector; WF1B Reflector
> > Subject: [WriteLog] Re: Kenwood TS570D
> >
> >
> > The question was asked and I forgot to mention, the TS570 is fully
> > computer controlled just like the '870 via a COM port with a DB9
connector
> > on the back of the radio.
> >
> > That's another thing that made it so much more enjoyable to me is that
> > for the first time ever at this QTH I was able to have computer control
on
> > both
> > radios.
> >
> > 73, Don AA5AU
> >
> > ----- Original Message -----
> > From: Don Hill <aa5au@msn.com>
> > To: WriteLog Reflector <Writelog@contesting.com>; WF1B Reflector
> > <wf1b-rtty@wf1b.com>
> > Sent: Friday, September 29, 2000 8:41 PM
> > Subject: Kenwood TS570D
> >
> >
> > >
> > > Sorry for the bandwidth, but I wanted to express my opinion about
> > > the Kenwood TS570D as a RTTY contest radio since I used one for
> > > the first time this weekend. W5ZE loaned it to me as a 2nd radio.
> > >
> > > I received the radio less than 2 hours before the contest. Without
> > > ever having operated one before, I was able to install it very easily.
> > > Since I have owned now two TS870's I was somewhat experienced
> > > with how it might work as far as menu settings and FSK/PTT connections
> > > were concerned.
> > >
> > > The '570 I used had a 250 hz filter in it and I used that filter the
> > entire contest
> > > period. I was very impressed with the radio and it worked very well
for
> > > me except for the fact that the filters are not as steep as what I am
> > used
> > > to in the '870 and when a station came very near, the S-meter would
> > > jump up and the audio would go way down.
> > >
> > > The only other problem I had with it was that the audio was low coming
> > > out of the PHONES jack. I always use receive audio out of the phones
> > > jack since it allows me to adjust the level. For most of the contest
I
> > had
> > > the VOLUME control set 3/4 to almost full on. There was no distortion
> > of
> > > the audio at that range and I felt that was a good thing from the
radio.
> > >
> > > I made over 700 QSO's with the '570 alone.
> > >
> > > For the price, the radio seems to be capable of being an excellent 2nd
> > > rig for RTTY contesting or even a primary rig for a beginner.
> > Hopefully
> > > AVVID can fix one of my TS-870's and I'll have dual TS-870's for
JARTS.
> > > I'm looking forward to that. But if my budget called for it, I'd buy
a
> > '570.
> > >
> > > 73, Don AA5AU
> > >
> > >
> > >
> > >
> > >
> > >
> > > -----
> > > Submissions: mailto:wf1b-rtty@wf1b.com
> > > Administrative requests: mailto:wf1b-rtty-request@wf1b.com
> > > WWW: http://www.wf1b.com/
> > > Questions about RTTY reflector: mailto:owner-wf1b-rtty@wf1b.com
> > > Questions about RTTY by WF1B: mailto:wf1b@wf1b.com
> > >
> >
> >
> >
> >
> > --
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>
> --
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>
>
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