Hi Scott & All,
Brian ZL1AZE referred to me your comment on your 10m RTTY contact with me
during the BARTG contest.
I have been away on holiday since the BARTG.
I am impressed that you worked me using your 40m dipole by mistake!
There are three factors working together that allowed me
to copy your weak signal. A signal that was so low that no RTTY tones were
audible.
The site, Quartz Hill (ZL6QH QTH) is on isolated elevated coastal farm land
and there is no man made interference - the receiver "sounds dead" until a
signal pops up.
The antenna is a remarkable 6 element 10m mono YAGI that looks like a giant
kite suspended from a catenary and tethered at the corners. The elements are
Al tube and the driven element is a three element dipole that is matched to
600 ohm open wire feeders back to a gantry near the building, and
transformed by balun to 50 ohm coaxial
cable to the antenna selection switch in the operating room.
I use a HAL DXP38 modem that is setup for weak signal copy. Bill Henry,
K9GWT writing in "The New RTTY Journal" emphasized the need to drive the P38
and DXP38 modems at a good audio level. I use the +12db setting for the
DXP38 which is a perfect match with the
AF out from my FT-1000MP.
So there you are;
SITE - ANTENNA - TECHNOLOGY
a killer combination!
Beside my contact with you Scott, two others stood out in the same manor -
signals that printed without audible RTTY tones - GU0SUP and GM0FGI.
Quartz Hill is an outstanding site with several long Vee's (300m) and a
Rhombic antenna. If any of you are contemplating a holiday in New Zealand,
stopover in Wellington and visit Quartz Hill - you will be made welcome.
73
Bob ZL2AMI
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