Understanding
Propagation
Contact Me: W7ACP
Welcome to South Western IDAHO
- South Western Idaho has a
very wide range of terrain, vegetation, wildlife
and climate. Here in Caldwell, we are at the
Western end of the Treasure Valley, formed
initially when the Yellowstone 'hot spot' was
located here. As the Yellowstone caldera has
moved (well, the effect of the caldera moved on
the surface - most likely the hot spot stood still
and the Earth's crust moved over it.), the
mountains created by tectonic action in the
collision of the North American Plate with the
Juan DeFuca Plate were 'melted' by the hot
spot. The modern day result is a valley
running from the Oregon-Idaho border toward the
Southeast to just North of the Idaho-Nevada border
then turns Northeast toward the present day
location of the Yellowstone hot spot in
Montana. This valley is surrounded on all
sides by the Rocky Mountains or its cut-off
remains in the ancient Owyhee Range. The
valley floor is around 2,400 feet above sea level
(at my location) while the surrounding mountains
and ridges run to about 6,000 ft to the South and
8-9,000 ft to the north. This has created a
very unique weather pattern for the valley, where
storms coming toward us from the West typically,
dry out as they leave the Owyhee's (to our South),
and start precipitation again when they hit the
Rocky's to our North, leaving us with an average
of 11 inches of rain and 8 inches of snow annually
while Idaho City, just a few miles away in the
foothills of the Rocky's receives an average of 27
inches of rain, and McCall, several miles to our
North and well within the Rocky Mountains receives
over 25 inches of rain and a whopping 138 inches
of snow annually. All of that describes how
the Treasure Valley and the Magic Valley are an
agricultural paradise. Lots of water (from
all that mountain snow), long growing seasons, and
when the fates allow, nearly 5 months of
continuous 'perfect' weather. All we need to be a
'destination' would be to have an ocean beach ...
but alas, what we have is called a 'High
Chaparral' where grass, sage brush and the
invasive Russian Thistle (tumble weed)
thrive. Where the land is not in active
farming we have endless tracts of 'BLM' (Bureau of
Land Management) controlled land that is generally
accessible to the public while also available for
ranching and in some places it is home to herds of
wild horses. My wife and I love to take
trips out into the desert (excuse me 'High
Chaparral') to see the sights, smell the smells,
and meet the wild or nearly wild life of the area.
- Some photos we have taken
from around the area click
here.
Station Equipment
HF Radio & RF Path
- Alinco DM-430T Switching 12v 30A
Power supply.
- Yaesu FTDX10 HF/50MHz 100W Hybrid
SDR Transceiver
- Morgan
Systems M-400X Broadcast Band Filter
3.5-5.4Mhz 200W 50 ohms (www.surgestop.com)
Updated 12/03/2021.
The various wave traps and other AM BCB filters
did not appear to work in part because I was
looking in the wrong place. FT8 being a
'weak signal' protocol was not dramatically
affected (or so I thought), and when I was
looking for other signals (mostly SSB) I wasn't
finding them. A big part of the reason was
that I had a lot of additional RFI from local
sources that had not been attenuated and these
sources signatures appeared to be IMD (repeating
equal frequency spacing). After dealing
with those, using the Palomar RFI KIt (below),
the Morgan M-400X was exactly what was required
to clean up the remainder. The difference
was a very dramatic doubling of the number of
FT8 decodes per period, and noise levels of S6
on 40M, S5 on 30M, S4-5 on 20M, S0.5 on 17M,
S0.5 on 15M, S0.5 on 12M, S1 on 10M and S0.5 on
6M. The increased ability to scan the band
and observe RTTY and SSB was very
dramatic. There are still discrete RFI
signals of both single frequency and 'fuzzy'
throughout the entire spectrum, some come from
one (and only one) of my two Windows monitors
(Scepter 20"), and as yet undiscovered
sources. The monitor's power cable has 3
turns through a 1/2" Ferrite (Fair-Right V0)
which does reduce much, but not all of the noise
from that source. I think what I'm seeing
is a signal generated within the monitor, and
given the low cost of the monitor plus the low
degree of interference I'm going to call that a
win.
- Palomar
Engineers Coax Noise Filter CMNF-500-50GB
<= 38dB rejection of common mode current
1-60Mhz.
- Palomar
Yaesu FTDX10 Transceiver RFI Kit 8
RFI/Noise Reduction Filters 3 ea. ring and 5 ea.
1/2" snap on beads.
- NOTE: When placing the 1/2" snap
on beads; take two or three turns of wires
through the center then gently close the bead
while watching the receiver, as the magnetic
field couples you will notice the effect in
reduced noise. If you have the wire length
(and diameter) to take more turns its easy to
adjust and test. When satisfied snap the
bead shut. As a practical matter, try
snapping a bead shut and getting it open again
without any wire to see how it's done, once in
place it may be difficult to determine. In
my case, the Scepter monitor power supplies were
creating a lot of noise, and five turns in each
power lead quieted the noise down to about 5.5dB
(+24.5dB on the FTDX10's waterfall).
- NOTE: DC Power leads that came
with the radio are quite long (about 6').
I installed the RFI Torroids with 14 turns
through the center, all in the same
direction. All of the ferrite chokes are
installed as close to the radio as is
practical. I installed one of the 1/2 ID
beads on the USB cable (from the computer for
CAT control and audio), I even put a choke on
the CW key line!
- MFJ
993B IntelliTuner Automatic Antenna Tuner.
NOTE: I really like this tuner! The FTDX10
has an internal tuner that can do quite wide
match, but this tuner can do so much more
it makes it worth the additional expense.
It has made my intentionally non-resonant 95.375
foot antenna wire (connected through the Palomar
'Bullet' 9:1 UNUN) functional on 80M through 10M
and it provides a 1:1 match to the radio most of
the time. What it's doing is coupling the
transmitters power into the transmission line,
UNUN and antenna. Very little reflected
power toward the radio. All that power is
either radiated as RF or as heat in the antenna
system. So far it appears to be radiating
RF far more than heat, as I increased my
'footprint' as seen on PSK reporter
significantly.
- MFJ 1708B-SDRS SDR Receiver
TR Switch
NOTE: This switch makes it possible to run the
RSP1a as a spectrum analyzer looking at the output
of the radio. It also allows the SDR to be
used to observe a wide spectrum of frequencies
while operating the transmitter.
- MFJ 1701 6 port Antenna
Switch common through NI4L
HF Choke Line Isolator (CM choke) to reduce RFI.
- SDR Play RSP1a (Software: SDR Uno) connected
through the TR switch to allow receive
operation even when transmitting from the
FTDx10.
- MFJ-1026
DELUXE NOISE CANCELING SIGNAL ENHANCER
This device uses a sense antenna and
amplifiers to invert local noise signals and
add them back into the receiver antenna input
during receive. It has a built in TR
switch that apparently MFJ is not very
confident in, but my transceiver doesn't have
a distinct TR output that is easily
accessible, so I'm relying on the built
in. Turns out that on my unit the T/R
Delay must be set to 0 (full CCW) versus the
10 (full CW) the manual specifies to allow the
TR relay to drop out at all. Many
YouTube videos describe the operation of this
unit, and a few even discuss the sense
antenna, but rarely do they delve deeply into
how it works. I intend to write up my
experience as an article on this web site, but
for now, my experience is that if you have an
end fed half wave antenna as your main
antenna, you are going to want a similar
antenna as a sense antenna. If you want
to use this device to reduce AM Broadcast Band
interference, it is essentially useless, and
if you want to use it to mitigate left over
local noise it might be possible, but it's
going to be difficult to setup and may need to
be changed as often as you change bands.
At the moment I'm thinking of removing it, but
I put it in front of the SDR, so I'm might
leave it in the circuit for a bit to
investigate using it with the SDR to create a
useful "PANADAPER".
Antennas
Narrowband Antennas
- Wolf
River Coils SOTA (Modified) tunable
vertical with ground plane 40M through 20M.
- TRAM
1480 VHF/UHF 6db colinear 5/8 wave,
mounted atop 8' of black steel 'fence top
rail'. Connected directly to BTECH
UV-25X2.
- MFJ-1979
17 ft collapsible (tunable) antenna - uses vary
from SDR input to active antenna for
comms. Recently re-installed for use as
sense antenna for the anticipated addition of an
MFJ-1026
Deluxe Noise Cancel / Enhancer / Antenna.
- HamStick antennas; 75, 40,
20, 15, 10 meter.
Uncategorized Antenna
Equipment
Retired Antennas
- Retired:
Alpha Antenna JPole Jr. 34'
End fed 'sloper' feed end at 30' AGL (Above
Ground Level) sloping to 10' AGL fed at
the North end with the wire sloping to the
South, so East/West should be strongest
signals, you would think, but read on!
VHF/UHF Radio & RF Path
Computer & Data Path
- Mac Mini - My office
workhorse; produces the secure (LetsEncrypt)
Internet presence for this web site, (Apache HTTP Server)
publishes several MySQL databases, handles all
storage, video, html editing, email, etc.
- Retired: Acer
Notebook - configured primarily for Application
Generation with AppGini for MySQL databases.
- Retired:
Toshiba Satellite Notebook - configured
primarily for Radio Control with DxLabs, WSJT,
and other radio control software.
Test Equipment
- Fluke 77 DVM (circa 1970, my
old friend!)
- NANO VNA Network Vector
Analyzer
- Looking for an inexpensive
100 Mhz dual trace storage oscilloscope. Thinking
about YEAPOOK ADS1014D among
others.
- NOTE: The RSP1a SDR makes a
fine spectrum analyzer to sample transmitted
signal. My current antenna is selected by a
switch box, then routed through the MFJ 1708B SDR
TR Switch to the RSP1a and the Yeasu FT10Dx
transceiver. When in transmit there is just
enough RF energy still present to provide the
RSP1a with a very usable sample. Good way to
check for modulation and spurious emission (my
first harmonic is less than 30 db down -
GOOD!) Tuning my audio card volume and
WSJT-X's power control shows that for FT8 mode I
can run the selected audio card at full volume,
and the program power level at 100% without
distortion and that I do not have to apply any
wave shaping to produce a clean transmit signal.
- 20210730 I captured this
screen shot from the Spectrum Analyzer app
running on the RSP1a. Conditions: WSJT-x
FT8 Tune mode with transmit frequency set to
1000 Hz, Power 100%, into Palomar 55 antenna,
sampled by RSP1a inline via MFJ 1708B.
First harmonic is -33db 4th harmonic is
-50.5db. The signal is averaged over 20
sweeps.
Yeapook ADS1014D
Oscilloscope
Software
- Skimmer (not until it works
with my SDR or another inexpensive one).
Skimmer is expensive - but it could be worth it
since there are few reverse beacons near me.
But not until I have a proven antenna system ...
- DXLabs - Best radio control,
DX, Contesting software, but it needs a native CW
decoder!
- WSJT - The best way to 'do'
FT-8 etc.
- JTAlert - Adds serious
functionality to WSJTx for things like 'worked
before' and 'Calling You'.
- NOTE: As of July 2021 I have
configured WSJTx and JTAlert to cooperate and
control FT8, logging (both local and LoTW) and
spotting. Working on how to automatically
and timely update LotW and QRZ logs.
- PSKReporter
- CWGet - Works off the
sound card, so it can work with DXLabs
Winwarbler.
- CHIRP - Allows programming
HT's to the same channel (frequency) etc. even if
they are different model numbers from different
manufacturers. But its a bit 'clunky' - I may have
a look at creating the same functionality using
some other tools and database(s).
|
Project List
Antenna Analysis
VNA analysis of my
antennas - or - Learning how to use VNA Windows
software.
4NEC2 modeling and analysis of antennas and antenna
design ideas.
Antenna
Install and Test
- Using a 30' flag pole to
'fly' a wire antenna and stay under the radar
(maybe).
As well as how well it works, and how much
sensitivity it has to installation direction.
NOTE: This project is mostly complete. The
Palomar 'Bullet' and 95.375 ft #14 THHN wire
antenna is designated antenna 'P95'.
- Using two 17M 'Hamstick'
antennas to form a vertical dipole, model and
test.
- If this works as I think it
will, these should make an ok DX antenna.
- Based on results, construct
a self supporting, vertical half wave 40M
antenna, then add additional vertical half wave
antennas to the structure to create a multi-band
40M-10M antenna with low radiation angle.
- Cut for FT8 operation,
these are the half wave antenna lengths:
- 40M 66.00'
- 30M 46.12'
- 20M 33.22'
- 17M 25.83'
- 15M 22.18'
- 12M 18.75'
- 10M 16.65'
- 4Nec2
Analysis HamStick
- 4Nec2
Analysis VDipole
- Relative ERP map by
skimmer/beacon.
Comparison to Wolf SOTA vertical
and other antennas.
Transact (or something) the DXLabs and WSJTx MS Access
log databases on JWIN into MySQL tables on JMAC so I
can archive, and manipulate, display etc. outside of
the applications. See if AppGini can ingest
'em? Otherwise use Open Office Db to enumerate
and export?
One Click Reports I want to write:
- List today's QSO's by time.
- List today's QSO's by band
and distance.
- List states & countries
QSO'd today.
- List outstanding QSL's.
- List QSL's by date/time.
Shack
Grounding
- Ground rod installed &
connected - working on eliminating noise and KCID
AM before I write it all up. The ground rod
is connected to a 'loom' which is usually found
inside an AC distribution panel, but in this case
is screwed directly to the wall behind the
desk. There are 9 positions, one ground
wire/equipment per. Currently using 1 for
the ground rod, and 4 for equipment grounds.
- I have found a bit of a
difference in potential between the 3rd wire
ground and the ground rod. I've made up a
jumper and plug that allows me to easily bond the
two grounds for testing and evaluation. So
far I have found no significant effect one way or
the other.
- Pending:
- Lightning Ground
- Signal Ground
- EMI Ground and Shielding
(I've got a great large (1490Khz/1KW) KCID AM
ground wave transmitter 500 yards to my
East). Working with Palomar Engineering to
get the RF (both mine and KCID's) on the coax
shield stopped before it gets to the radio using
filters and chokes.
Radio Continuity of Operation
- New battery for UPS
- Power OP strip from UPS
(JMac & display, JWin & displays, ext
drives, HF, VHF & UHF radios, HT charger.
- New automotive/deep cycle
battery for transmitter(s)
- Solar charger.
- Recharge all radio and
UPS batteries.
- Switch radio over from
commercial to battery. Temporary immediate
phone, CW only.
- Generator
- Switch house (RV) and
entire shack to generator (change 50A and 30A
source from commercial to genset), consider
FrostKing heat tapes etc. Temporary all modes.
Reduce QRM on 160, 80, 11, 10
meter bands due to KCID and general noise.
DMR Digital Mode Radio
ICOM ID-51 Docs
Delta
Loop Antenna(s)
Completed Projects
|