wrote:

Can't such interference be dealt with using a notch filter? A PSK31
signal is only a few dozen Hz wide, for example.

The short answer is yes. The longer answer is that we have all these
wonderful controls on our radios, sometimes we need to use them.

I learned a lot about CW filters, PBT, notching etc, with my PSK31
waterfall setup. As you invoke and adjust the various functions, the
noise floor of the waterfall gives a nice graphic display of what each
filter does.


Even more basic, isn't it the responsibility of all operators to avoid
transmitting on top of existing QSOs? Why would digital ops behave
differently in this regard when faced with 'phone signals vs. CW
signals?

Yes, and they don't as far as I know.

I think that on some bands, such as 20 meters, a person can accidentally
stomp on another due to propagation, So often we only hear (or see) one
side of the QSO. We fire up, and soon the Ham we can hear and can hear
us tells us of our error.

I wonder what frequencies G4JCI is referring to? And note to G4JCI:I
think you might have a typo in your call sign, there isn't any reference
on QRZ to that call.


- 73 de Mike N3LI -

Michael Coslo wrote:

I think that on some bands, such as 20 meters, a person can accidentally
stomp on another due to propagation, So often we only hear (or see) one
side of the QSO. We fire up, and soon the Ham we can hear and can hear
us tells us of our error.

I wonder what frequencies G4JCI is referring to? And note to G4JCI:I
think you might have a typo in your call sign, there isn't any reference
on QRZ to that call.

The call is perfectly OK since around 1977, in the UK we have a privacy
option which stops the RSGB and others including us in callbooks etc.
The call was previously ZS6N but that has since been re-issued to
someone else after I left ZS land in 1982.

My point is that here in Europe we have to get by with a concealed
wire antenna in the attic and QRP to avoid TVI complaints etc.
All too often some clown (usually in the USA) can barely hear us and
cranks up with a few kilowatts and an antenna farm. This same clown
usually gets a 30/9 report from someone and chews the rag for half
an hour at the same output instead of reducing power to the minimum
required to maintain communications.

It is this inconsiderate behaviour which gives USA operators a bad
reputation in the rest of the world. Of course there are plenty
of good guys out there, as always it is the bad operators who set
the bad standards.

g4jci

In article ,
Michael Coslo wrote:

I think that on some bands, such as 20 meters, a person can accidentally
stomp on another due to propagation, So often we only hear (or see) one
side of the QSO. We fire up, and soon the Ham we can hear and can hear
us tells us of our error.

That can happen on any HF band, I believe.

This issue was behind a lot of the protest over one aspect of the
ARRL's now-withdrawn "sub-bands by bandwidth" proposal. The proposal
had suggested opening up a much larger portion of the band to
unattended and semi-attended digital stations (typically, email
servers). Such systems are rather notorious for "stepping on" QSOs in
progress, due in part to this "only can hear one half of the existing
QSO" problem.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Dave Platt wrote:
In article ,
Michael Coslo wrote:

I think that on some bands, such as 20 meters, a person can accidentally
stomp on another due to propagation, So often we only hear (or see) one
side of the QSO. We fire up, and soon the Ham we can hear and can hear
us tells us of our error.

That can happen on any HF band, I believe.

True, I used 20 meters as an example because it is the most common band
with the "worst" problem.


This issue was behind a lot of the protest over one aspect of the
ARRL's now-withdrawn "sub-bands by bandwidth" proposal. The proposal
had suggested opening up a much larger portion of the band to
unattended and semi-attended digital stations (typically, email
servers). Such systems are rather notorious for "stepping on" QSOs in
progress, due in part to this "only can hear one half of the existing
QSO" problem.

Many is the time that those robot stations have obliterated the PSK-31
segment of 20 meters. Two of them close the band. They don't check, they
just start transmitting, and they keep it up, presumably until they get
acknowledgment from another robot station.

It got so bad that Digipan added a decoder for the mode (no transmit) so
that we gould catch the callsigns, record the disruption, and and turn
them in to the FCC. Apparently this worked, because the problem is
diminishing.

- 73 de Mike N3LI -