Hi John,

Good to hear from you again on the newsgroup, and to read your observations.

A few thoughts:

The RF environment where a receiver is used definitely figures into the
equation. I believe it's Vince or Gary in your country that uses the FRG-7,
and he has said that his DXing location is far from local transmitters. That
can make a big difference.

In the same way, John's use of the Eton E1 on Easter Island is fully
appropriate, as there are no local MW stations there, and only 1 low-power
FM. Easter Island's nearest concentration of MW stations is 2300 miles away
on the South American continent, and Australia/NZ is about 4300 miles
distant! It doesn't take a crunch-proof receiver front end to perform well
in such a location.

The scarceness of local noise and nearby powerful stations is also a reason
the early pioneers in radio and DXing had such phenomenal catches in the
1920s-1940s, despite their very simple receivers.

I chose the SDR-1000 largely on the strength of its front end and close-in
dynamic range/IP3, for use here in the greater Seattle/Tacoma area. I have
many MW frequencies registering S9+50db, and a number of them are at S9+60dB
or greater. The strongest I've seen was -13dBm on the SDR-1000's very
accurate and calibrated (dBm) signal meter. This is when I was using the
Beverage antennas in the greenbelt (forested) area behind my house. In
direct tests at my home, the SDR-1000 clearly heard weak DX that was
inaudible or muffled in the noise on a Ten-Tec RX-340 (two different units).
However, the same rigs side-by-side at the Grayland DXpedition location
performed equally as well. I've heard a number of 9 kHz "splits" at home
with the SDR-1000, such as 1475 kHz RTM Malaysia in Kota Kinabalu, that may
not have been quite as clear and strong with another radio used in the "RF
alley" here.

With the Perseus receiver I have on the way, the front end may be slightly
less "stout," but it has operational advantages over the SDR-1000 that make
it very worthwhile for both home and DXpedition use.

73,

Guy Atkins KE7MAV
Puyallup, WA USA


wrote in message
...
Receiver test data from
S = Sherwood
P = Passport
Q = ARRL QST mag

5 KHZ THIRD ORDER INTERCEPT DYNAMIC RANGE

dB
100P Icom IC-R9500
93Q Flexradio SDR-1000
82S AOR7030
80S Icom R7800
78S Icom R781
78Q/75S Icom IC-R756 PRO III
77Q/75S Icom 756 PRO II
77P Drake R8A/B
77S NRD 515
75S Drake R7
75S WJ-1000
74P WJ-8711
71S Icom 756 PRO
71S Drake R8
68S/66P NRD545
67S Icom R75
67S Drake SW8
64S Yaesu 7700 (similar to FRG7)
62S Icom R70/R71
55P Eton E1 portable
46S Ten Tec 340
43P WinRadio 313i

The above data is supposed to indicate which of your dream receivers
will get you that ultimate DX catch above all other receivers. In
practice, life is different: one of my pals had a SDR-1000 and I
didn't notice his logs reflect anything much better than other
fella's. A top DXer John Bryant used a Eton E1 on a DXpedition to
Easter Island and logged some of the best catches I have ever seen.
See:
http://www.dxing.info/dxpeditions/easter_island_2007.dx

I have a pal who insists on DXing with an ancient battered Yaesu FRG-7
and i would rate his fantastic logs and high quality recordings
amongst the very best in the world, yet the FRG-7 is actually a very
poor receiver from a poor front end and sloppy bad filters point of
view. A few years ago a DXer won the prestigious Danish DC Club annual
contest with an equally modest receiver, a Yaesu FRG-7000.

A lot of my co DXer's are now using SDR-IQ's and achieving amazing
results, whilst the top rated AOR 7030 lads don't seem to be getting
much in the way of spectacular catches lately.

So what's the motto of this story; just this, don't worry about
receiver specs just concentrate on going on a decent DXpedition to a
good radio spot and make sure you get a decent antenna up.

Have fun and good DX

John Plimmer, Montagu, Western Cape Province, South Africa
South 33 d 47 m 32 s, East 20 d 07 m 32 s
RX Icom IC-756 PRO III with MW mods
Drake SW8 & ERGO software
Sony 7600D, GE SRIII, Redsun RP2100
BW XCR 30, Sangean 803A.
Antenna's RF Systems DX 1 Pro Mk II, Datong AD-270
Kiwa MW Loop, PAORDT Roelof mini-whip
http://www.dxing.info/about/dxers/plimmer.dx