In article ,
"Michael" wrote:

"Telamon" wrote in message
...
In article ,
"Michael" wrote:

"Telamon" wrote in message
...
In article ,
Tony Meloche wrote:

dxAce© wrote:

Michael wrote:

"starman" wrote in message
...
Michael wrote:

"starman" wrote in message

Can you give us some examples of the weak signal stations
you receive on the R-75 with ECSS? What kind of antenna do
you use for these DX stations?

Thanks


DX'ing weak signals have just as much to do with
"conditions"
as they do with the power and distance of the transmitted
signal. It may be very easy to get say...RNZI from my
location during times of the day and year when conditions
are
good for it, and impossible to pick it up during other
times.

I've used ECSS to identify weak carriers too but I was
wondering what you would consider a good DX catch. What have
you heard lately that you would classify as weak DX, given all
the "conditions"

Half of what I listen to is dx, including hams from around the
world. If you need a single example, I'll say .. How about
right
now.... 21:50 UTC on 7.190 .... I'm listening to what I think is
Tunisia. Currently Arabic music. The signal is barely s-3 and
it
is quite noisy. The same exact signal is also being broadcast
on
7225. Still a bit noisy with fade out, but it makes it all the
way up to s-7.

I'd call this DX, but not a VERY weak one. It is far away, and
it is messy. The drill here on this signal is to use all the
tools at my disposal to clean it up and see how good I can get
it
to sound... IE: ecss, filters, gain, nb, nr... etc.....

About S8 here on both frequencies.

Steve Holland, MI Drake R7, R8 and R8B


To be fair, though, Steve - that probably has as much or more to do
with your antenna farm (I've seen the pics and read your description
- it's terrific) as it does your reciever.

Steve does have good antennas but the Drake R8B is very sensitive. One
thing about different manufactures is their attitude toward
specifications. Some rate their product more conservatively than
others. Just something to keep in mind perusing the specifications
between different manufactures of radio equipment.


I don't think the difference between him picking it up on 7225 as s-8
and me
picking it up as s-7 is enough of a difference to base it on his
receiver
being more sensitive. It is hardly any difference at all. If I
checked
the meter ten seconds later, mine might have been at s-6 or s-9 the way
it
was coming in and out.

The Drake R8B and Icom R-75 have about the same sensitivity so I don't
think that is the difference.

One real question here... And one that I'm interested in.... Why would
I
get it on 7190 at only s-3 while he gets it as s-8 ??? We're both
getting
it about the same strength on 7225, so why should we be getting such a
measurable difference on 7190 ??? I'd say it probably has more to do
with
the peculiarity of our locations in respect to the transmitter and what
ever
comes between them rather then our receivers.

The signal in question is from the other side of the world compared to
the difference in distance between the two of you is small so location
is not likely the answer.

Lots of other possibilities here.

The sensitivity numbers for the receivers are general numbers. The
actual sensitivity changes with frequency because the front end of the
radio is not completely flat. Could be your R-75 has a bigger reflection
at 7190 but this is not the likely reason either.

Most likely the antenna itself or whatever you have for matching it to
the coax is the reason. Your antenna system most likely has a poorer
response at 7190 compared to Steve's system.


I tried both my dipole and my 200 ft roof wire on both signals and both of
my antennas received the signal on 7190 substantially weaker then that on
7225. I bet if you set Steve's antenna and receiver up here at that time,
you'd get the same difference in the two signals. I don't think it is the
antenna or the receiver. Something else is going on. I know both Steve and
I are in North America, but, we are far enough away (NJ vs. MI) to have our
locations effect how we receive the signal. For all I know, the 7190 signal
comes out of a different antenna set up that just happens to be favorable to
Steve's direction. I think that is where the real study is here. To find
out what difference if any that there is between the two signals. Are they
coming from two different antennas ???

Michael, you and Steve are not far enough apart for another hop through
the ionosphere so you are about the same reception distance from the
source.

It most likely has something to do with an adverse reactance in your
antenna / matching unit / coax to your radio.

--
Telamon
Ventura, California