Hi Mike and all who responded.
I guess I was just underwhelmed at what I could accomplish on FT8
vs CW on 160. I figured it would open up a whole new level of rare
countries and places that were now workable to me. Working Kazakhstan on
160 CW from my location is difficult, but doable on some nights in the
winter. On FT8 I hear UN1L often, but I can never work him after many
days of trying. I started out with 90 watts and ended up with 900 watts
output, but never a response from him. I guess 160 is a special case
where achieving a good receive noise level is very difficult. FT8 must
be a huge improvement for those, as you said, with few radials and
smallish vertical radiators as their sole antenna. The extra 5 or 6 dB
must be the difference of night and day for limited space or limited
antennas in general. It sure has fostered much activity on 160 with
calls that are mostly unfamiliar to me. I have worked a few regulars on
FT8, like YO3APJ, and they seem to hear just fine. Unfortunately I am
not QRV on other HF bands to try out FT8 there! I suspect the ALLIGATOR
SYNDROME is not as evident on the higher HF bands.
On another subject, I ran out of room on my six position receive
beverage coaxial switch. I had seven beverages, and one was not hooked
up as a result. I also have not been using diversity reception even
though I am using a K3. So I finally worked out a plan to make a new
switching box. It consists of two Grayhill 12 position rotary switches.
The two switches have a set of the 12 positions wired in parallel
between the two switches and each position connects to a rx input jack
on the back, while the common terminal for each switch goes to the main
rx jack or the diversity rx jack on the K3. The 12 inputs are "F"
fittings on the back of the switch box. I worried that the isolation
would be poor, but it checks out at 55 to 65 dB on 160 and 80 meters.
VSWR is pretty good too even with all the insulated wire used. I did not
even try wiring it with coax! One switch selects any of 12 beverage
antennas for the main receiver, while the second switch selects any of
the beverages for the diversity receiver. It works very well and I
wonder why I did not do this a long time ago. In the first evening I saw
a huge improvement using diversity and it was nice having all the wires
available too! Too bad it won't get much use until next fall and winter!
73
Dave K1WHS
On 4/23/2018 3:50 PM, Mike Waters wrote:
Hi Dave,
I think it's safe to say that you're running Beverages in a very quiet
location, and the hams that can't hear you are not. What is more, they
might have a 20 over 9 noise level and are running non-directional
antennas (such as verticals with no radials or low dipoles).
73, Mike
www.w0btu.com <http://www.w0btu.com>
On Mon, Apr 23, 2018, 10:36 AM David Olean <k1whs@metrocast.net
<mailto:k1whs@metrocast.net>> wrote:
I have been playing around with FT8 on 160M and am a bit puzzled.
I have
made plenty of contacts, but with many stations, it seems to
require an
inordinate amount of power to get their attention, or they do not
respond at all. I also have noted that I can hear in a 2.8 kHz
passband,
signals that register from -12 to -17 dB. About the weakest that I
see
is a bit more than -20 dB. Does this mean that FT8 is only a few dB
better than CW? I have my time set accurately and I try to place
my TX
signal away from whomever I am calling on a clear spot on my
waterfall.
Some stations are easy to work, and I have worked across the country
(FN43 to a CM grid) running just 1 watt. It just seems that there are
many stations that are not hearing much, but are making plenty of
noise. Am I wrong?
I am working on cleaning up my 160 setup and have 8 beverages running
and they are all pretty quiet now that I installed plenty of ferrite
chokes around on the RG-6 feed lines. I am looking forward to
next fall
and winter.
73
Dave K1WHS
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