Topband: 160 conditions

[Bill Tippett]

W7IUV wrote:
 >It's very disappointing that the VK9 and HS can't hear my
1500 watts and 90 foot top load vertical with over 80 radials.
I have to wonder just how much power it takes to break through
their noise level.

         Larry, I can only speak for myself, but here is what
is probably required:

1.  HS72B's signal must be clearly readable.  That does
not necessarily mean moving your S-meter, but at least 559
by ear.  You don't want to be calling anyway unless you
can clearly hear him respond.

2.  I'm running the legal max 1500 watts to a 3 element
vertical parasitic array.  It models at 5+ dB gain like
a 4-square.  I'm also feeding it with a 0.2 dB loss line.
This is overall ~6 dB improvement over the single vertical
and feedline I was using a year ago.  I converted to this
array one day last February after UK9AA couldn't hear me.

         With the conditions we had today, you would probably
need an ERP of ~6 kW.  This can be done in other ways,
but the only legal way to do it is with antenna gain.  Of
course conditions could improve 6 dB and bring him within
range of guys with simple antennas.  XZ0A had several days
when he worked guys running simple verticals (myself
included then) and this could definitely happen again if
conditions improved just a little.  Of course Robin and
Dietmar are continuing to improve their RX situation and
hopefully identify the source of the noise that has been
giving them problems at times.  Every 1 dB improvement in
S/N at their end will directly benefit weaker signals.

         Like K1GUN, I was thrilled to simply hear 9N7BCC's
signal yesterday.  However I didn't even bother calling
since I felt he would have to be 579 here for him to
hear me over their local noise.  Unlike HS72B, there is
little more that Ben can do to improve their receiving
situation.  He told me 9N1AA has identified a nice rural
location with room for Beverages, but that must QRX
for someone else to exploit in the future...hint, hint
Dietmar and Robin!

                                                 73,  Bill  W4ZV

P.S.  I may forward the message Ben sent about their noise
situation.  It explains why 9N7BCC has such trouble hearing.