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Hello Jamey,
There are two differences in the measurements.
The one that I would track first is power. The analyzer is <10mW, the 7100 is watts. If there is a near short such as a stray ground braid wire or a insulator O ring that is off center it may cause a problem at higher power.
Try reducing the 7100’s power and remeasure. At minimum power the SWR reading may be off a little, that isn’t important for the test.
The second item is the 7100 is grounded to the vehicle, I doubt the analyzer was. The antenna and cable as a system may be 1.2:1 but once the cable end is grounded at the radio it may be different.
Try touching the connector at the analyzer to ground and observe the SWR. If it changes significantly you found the problem.
I can think of a couple of other possible causes but they are a stretch.
Let me know how it goes.
<p style=”text-align: left;”>Hello Joe,</p>
You should get a number of suggestions and options. The following is my limited experience.Ira (KC1EMJ) and I both got an Icom IC-7100. We both like the sound and performance of the radio on HF SSB. It is very clear and crisp. It has a small head unit that is easy to mount and the main unit with the supplied interconnect cable can be mounted in the back or trunk. The radio covers HF, 6, 2, and 70cm. With a mag mount it is a great 50w 2m/70cm setup.
We both had MFJ loaded mono band verticals for 80m, 40m, and 20m.
We set out to test the local range. My expectations were low from other ground wave experiments using the home shack but it was still disappointed on the 3 bands. 80m was the least bad. When Ira and I were on hill tops 15 miles apart we managed a 5/3 and a good QSO. As soon as we left the hill tops we lost the signal.
When we were closing range on Rt-122 in Hollis and Amherst we were within a few miles before we could copy each other.
At the same time we could both hear and work ECARS net control in NJ.
Ira, using the same mobile setup during his return from FL worked me from 5 states. I was using my home shack.
I wrote an club article on a 20m dipole hung as a vertical. I used the RBN and WSPR to collect SNR data. The few local network nodes report low SNRs, lower than many that were over 6000 miles away.
Based on my experience ground waves are not reliable for local HF communications.
I have helped develop and test a HF vertical for Army vehicles. These antennas are rear mounted and tethered to the front bumper to arch over the vehicle to support NVIS. Local to 100 mile comms were spotty but often available.
Hello Thomas,
You asked how old is the PC, and how it’s running now.
The PC used Windows 8 when first released so it isn’t very old.
It had a very large GB file on the desktop on a slow HDD causing a long startup. Dennis and I did a fresh Windows 10 install on a .5TB SSD and moved some files off the desktop onto a backup drive. Now a cold boot takes about 15 seconds…
Hello Dave,
Nice app. It could be useful to use it to capture a time lapse of one of the 20m beacons over a day or several days. There are beacons 20m-10m across the globe.
You would be able to see what time propagation is best to the beacon’s location and the day to day variation.
73
Hamilton
Hello Jeff,
The USB to Serial converters based on FTDI or SiLabs chips are recommended. The drivers are easy to download. The converter Jeff identified is FTDI based.
I would stay away from converters based on the Prolific chip sets.
Hamilton
Hello Dennis,
I’m available to help, I’m sure others will step up.
I will not tolerate W-10 taking more than 45s for a cold startup. Delays are often due to virus software, apps running in the background, and apps attempting to connect to the internet with broken links.
Insufficient memory, disk space, or a ancient processor can already lead to lengthy delays.
Hamilton
Here is an example;
It is a high pass filter and a low pass filter with a common connection which is why the frequency range of the ports can be so wide.
They are not directional, you can RX or TX from the common to a port or a port to the common.
Hello Bammi,
The solution is a duplexer, some call it a diplexer.
It has a connector for 2m/70cm, a connector for 2m and a 3rd connector for 70cm.
It is bidirectional and can be used to separate the two bands on one feed to two separate feeds which what you are looking for.
It can also be used combine two bands onto one feed.
DX Engineering and HRO stock them.
73
Hamilton
Hello Michael,
A portable AM radio (not FM) is a good initial sniffer. Any QRM will be strongest in the AM broadcast band and reduces at higher frequencies.
If you discover there is strong QRM near the power lines you can walk along the power line route in a attempt to locate the hot spot.
I found the noise peaked a 1/2 mile from my house. Eversource came out the same week I called them. They replaced a damaged insulator.
If you find the QRM near the line is the same as when you are well away from the line you should be ok. If it is ok in the AM BC band it will only get better in the higher bands.
Hamilton K1HMS
Hello Mike,
<p style=”text-align: left;”>I have a article on a 20m vertical dipole on the club website. As a vertical it has a low elevation pattern (aka takeoff angle) making it great for DX but not for regional QSOs. It is omnidirectional and very quiet.</p>
Since it is a dipole it does not need ground radials like a ground mounted 1/4 wave vertical therefore ground losses are reduced making it a very efficient antenna.At less than 1/4 wave above ground a horizontal dipole will have a near vertical takeoff angle and will be nearly omnidirectional. It will be better for regional comms but less effective for DX.
As you approach a 1/2 wave above ground the takeoff angle of a horizontal dipole will decrease making it good for DX and it will become more directional.
To your question; If you want to cover your state and a few adjacent states a low horizontal dipole is better than a vertical dipole.
For really long distance DX I prefer the vertical dipole. My high horizontal dipole is a close second but rarely out performs my vertical dipole. Both are next to useless for comms in my state and adjacent states which is a problem during 13 Colonies or the NE QSO party. To fill the gap I added a low (45′ AGL) 80m inverted V.
73
Hamilton K1HMS