On Jul 1, 2:56*am, John Plimmer wrote:
The ALA1530 active antenna arrived on loan on the 30th June
* The ALA is mounted on the same pole as the RF Systems DX1 Pro,
but about 1 m down, so
it is about 10m off the deck and is orientated N/S.
I have checked the continuity and the ALA1530 is working fine with
full
power at the head.
On LF the DX1 Pro hears things that are unheard on the ALA
e.g. 515 CW, MAJ Majuba is quite clear on the DX1 but not heard on the
ALA1530, and the same with various others.
252 LW Germany faint on the DX1 but unheard on the ALA
361 CW ASN Ascension clear on the DX1 but barely audible on the ALA
More or less the same on MW band - DX1 is much clearer and stronger
1050 MW Brazil quite clear on DX1 but unreadable on ALA
Then I worked the HF bands from 3 mhz up to 18 mhz
Here the DX1 remains the strongest and clearest, but the ALA also puts
in a
good performance.
RFI and noise suppression. I didn't notice that the ALA was quieter
noisewise than my DX1, nor does it suppress the harsh RFI I have here.
I did
spend a half hour with the help of Willie and Dawn rotating it in
various
directions, but it could not suppress the RFI noise.
I have always had the opinion that the DX1 Pro is a superior performer
as
I have had some outstanding catches over the years.
_________________________________
John Plimmer, Montagu, Western Cape Province, South Africa
South 33 d 47 m 32 s, East 20 d 07 m 32 s
Icom IC-7700, Icom IC-756 PRO III with MW mods
ERGO software
Drake SW8. Sangean 803A
Sony 7600D, GE SRIII, Redsun RP2100
Antenna's RF Systems DX 1 Pro Mk II, Datong AD-270
Kiwa MW Loop.http://www.dxing.info/about/dxers/plimmer.dx
I use the ALA100 with my own loop. You can get more aperture by
rolling your own loop, and you save a bit of money. Also, you can make
it into a portable system. The ALA100 is a fantastic product with one
big bug, namely the use of a BNC on a device that could be used
outdoors. [You need to put it in a NEMA box for permanent outdoor use.
Now granted, I've bought lots of pro-gear that expects NEMA box use a
well, i.e. the assume you are doing system integration.] Also note
that the Wellbrook loops are not shielded. They interact with whatever
metal is nearby.
Note that the Wellbrook 1530 loop isn't big enough for LW. They might
say it is, but trust me, it isn't. Using the ALA100, it doesn't begin
to really kick ass until you have about 25ft of wire on it. I've used
40ft loops in the boonies.
I've been testing out my antenna using HFDL, which gives you position
data on the transmitting source.
http://www.lazygranch.com/temp/pchfd...07012009_1.jpg
http://www.lazygranch.com/temp/pchfd...07012009_2.jpg
This is 7000 statute miles of data reception, a tougher criteria than
CW or voice. The noise rejection of the Wellbrook design helps under
these conditions.
I've done side by side comparisons with the KIWA loop. The KIWA isn't
as good as my ALA100 setup IF (big if) you use a good radio. The KIWA
is filtered, so it often covers up for the lack of filtering in your
receiver.