Bill, you wrote...
>As an owner of a ICOM 746 with INRAD CW filters for a second radio , I can
>tell you mine hears what appears to be key clicks on ANY strong CW signal.
>I attenuate the signal by 10 or 15 dB and that "cures" the problem.
>Furthermore, I've noticed that a signal with clicks can be "cleaned up" if
>another strong signal appears just below the nose of the I.F filter. I
>suspect the AGC is reducing the gain and this results in what suddenly
>appears to be a clean signal where before there was clicks.
If the offending station is CW, and the "strong signal" is also CW, then the
clicks would appear on some bits but not others. That is not the case here.
Many sigs have clicks that are many kHz away.
I have a 746 and listen with interest to multiple signals that run 20-30
over S9 and are clean as a whistle. I listen to other "offenders" running a
mear S8 or S9 and there are clicks all over the place--attenuators in or
out--many kHz away. I have a friend running a Kenwood rig and we talk on 2
meters all the time. He confirms what the apparently defective design of
the 746 also illustrates--CLICKS!
To blame the receiver is a simple way of saying "it's not my problem." To
label the empirical results posted earlier as flawed simply because they
were on a 746 is a joke. Although I wish he had also listed the S meter
readings and the status of the preamp/attenuator controls, the basic thesis
presented warrants investigation, contrary to your defensive posting.
If an owner of the FT1000X wants to take the time to actually measure their
output, as many postings to this reflector have admitted, they will see that
their signals actually are MALICIOUS INTERFERENCE during any period, not
just contest periods.
Ford-N0FP
ford@cmgate.om
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>From Michael Tope" <W4EF@dellroy.com Thu Mar 8 11:29:36 2001
From: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Subject: [CQ-Contest] Clicks
References: <3.0.6.32.20010307075136.00795a60@pop.gscyclone.com>
Message-ID: <0b3301c0a7c3$0e7e6680$6401a8c0@neptune>
With regard to Bill's comments on signal strength, one has to be careful to
distinguish between S9 signals on a open band with the receiver gain wide
open, and a 40 over 9 signal that has been attenuated at the receiver to S9.
In the latter case, all the band noise and QRM is dropped 40 dB along with
the offending signal when the attenuator is switched in. In this case, if the
clicks 40dB down, they will still be equivalent to an S9 signal, and hence
may be audible above noise and interference floor. In the former case, the
clicks from that same signal will be 40 dB below S9 or around S2. If the
band noise and interfernece floor is sitting at S4, you probably won't notice
them as readily.
73 de Mike, W4EF....................
----- Original Message -----
From: "Pete Smith" <n4zr@contesting.com>
To: <cq-contest@contesting.com>
Sent: Wednesday, March 07, 2001 4:51 AM
Subject: Re: [CQ-Contest] Clicks
>
> At 05:14 PM 3/6/01 -0500, Bill Fisher W4AN wrote:
> ...I have noticed what I'll call key clicks are getting worse and worse
> >on the bands. Normally, this phenomina can be observed when signals are
> >VERY strong. The same signal that produces clicks at 40 over S9, will
> >appear "clean" at S9.
>
> Reading this statement made me uncomfortable at the start. If cranking in
> attenuator makes the clicks go away, then I would wonder whether they are
> being produced in the receiver. I know that my TS-930, which has a good
> reputation for handling overload well, behaves exactly this way on many
> signals. Others, however, still produce off-frequency clicks and splatter,
> even when reduced to under S9.
>
> I'm afraid that receiver-based tests are never going to persuade
> manufacturers to clean up their act. Why can't we contesters persuade the
> ARRL to add an appropriately designed test or tests to their transceiver
> reviews? It would be even better (but maybe utopian?) if they could be
> persuaded to run a comparison of the top half-dozen contest radios for
> transient off-channel garbage on both CW and SSB. W8JI's already explained
> how this could be done from a technical standpoint, and the ARRL has proved
> open to changing its test procedures in the past when presented with a good
> idea...
>
> How about it, HQ? Anyone reading the mail?
>
> 73, Pete N4ZR
> Contesting is!
>
> The World Contest Station Database
> is waiting for your input at
> http://www.qsl.net/n4zr
>
>
> --
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>
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>From Michael Tope" <W4EF@dellroy.com Thu Mar 8 11:30:36 2001
From: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Subject: [CQ-Contest] Clicks
References: <3.0.6.32.20010307075136.00795a60@pop.gscyclone.com>
Message-ID: <0b3801c0a7c3$32603100$6401a8c0@neptune>
I am curious if there are any standards for measuring click performance? In
other
words, how do you attach a number to a transient event like a key click? N0AX
described a procedure for measuring key click performance using a spectrum
analyzer. How does one correlate the spectrum analyzer readings with what is
acceptable and what isn't? Obviously lower spurious readings on the spectrum
analyzer are better than higher ones, but how good is good enough? All our
rigs,
have finite phase noise, harmonics, and IMD performance yet at some point we
say - "good enough" - its a clean rig.
Mike, W4EF................................................
----- Original Message -----
From: "Pete Smith" <n4zr@contesting.com>
To: <cq-contest@contesting.com>
Sent: Wednesday, March 07, 2001 4:51 AM
Subject: Re: [CQ-Contest] Clicks
>
> At 05:14 PM 3/6/01 -0500, Bill Fisher W4AN wrote:
> ...I have noticed what I'll call key clicks are getting worse and worse
> >on the bands. Normally, this phenomina can be observed when signals are
> >VERY strong. The same signal that produces clicks at 40 over S9, will
> >appear "clean" at S9.
>
> Reading this statement made me uncomfortable at the start. If cranking in
> attenuator makes the clicks go away, then I would wonder whether they are
> being produced in the receiver. I know that my TS-930, which has a good
> reputation for handling overload well, behaves exactly this way on many
> signals. Others, however, still produce off-frequency clicks and splatter,
> even when reduced to under S9.
>
> I'm afraid that receiver-based tests are never going to persuade
> manufacturers to clean up their act. Why can't we contesters persuade the
> ARRL to add an appropriately designed test or tests to their transceiver
> reviews? It would be even better (but maybe utopian?) if they could be
> persuaded to run a comparison of the top half-dozen contest radios for
> transient off-channel garbage on both CW and SSB. W8JI's already explained
> how this could be done from a technical standpoint, and the ARRL has proved
> open to changing its test procedures in the past when presented with a good
> idea...
>
> How about it, HQ? Anyone reading the mail?
>
> 73, Pete N4ZR
> Contesting is!
>
> The World Contest Station Database
> is waiting for your input at
> http://www.qsl.net/n4zr
>
>
> --
> CQ-Contest on WWW: http://lists.contesting.com/_cq-contest/
> Administrative requests: cq-contest-REQUEST@contesting.com
>
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