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Hi Jeff,
I just went through the Field Day specific rules. You can view a copy via this link. I don’t see any reference to use of spotting assistance in the FD rules. The rules do say the following –
9.2. See “General Rules for All ARRL Contests,” “General Rules for All ARRL Contests on Bands Below 30 MHz,” and “General Rules for All ARRL Contests on Bands Above 50 MHz” for additional rules (www.arrl.org/contest-rules) that may cover situations not covered in these Field Day rules. Decisions of the ARRL Awards Committee are final in adjudicating Field Day problems.
Based upon this, I’d say the the General Rules for Contests above 50MHz would apply. Lets discuss this some more at our Field Day meeting on Monday.
73,
Thanks for posting these. Anita and I are headed to Dayton and we’ll be on the lookout for these and other new gear of interest.
73,
Here’s a link to some pictures from our class.
73,
Hi Murray,
Mobile HF is a pretty involved topic and requires much more than a good antenna to work well. You can get some idea of what is involved in building a good mobile HF setup via our blog here.
A good bit of work is needed on the vehicle where the Mobile HF station is installed in terms of bonding, grounding and possibly the electrical system as well if the installation is to perform well.
Why don’t you look over the blog post in the link above. If you want to tackle the project after reading the material, lets talk live about it when we see each other next.
73,
Hi Tony,
Driving the rod into the ground 2 – 3 ft from the house is a good distance. When you disconnect you coax, you’ll want to get the end well away from the rod as you suggest.
Try using screw in ground anchors. Here is an example of some effective ones available from DXengineering. You’ll need a metal rod that is strong enough to turn them into the soil.
Hi Tony,
If you can use the same ground rod for your feeling and your radio, then having the rod close to you house so that the ground connection between the rod and your radio is as short as possible.
I would suggest putting a small water pale over the top of the rod/suppressor to protect the connection that you can disconnect. If you disconnect your feed line and separate it a bit from your ground when not in use, then its not as critical to bond your radio ground to your electrical service ground. What you are trying to prevent here is a situation where lightening hits your antenna, follows the coax to your ground and then to your radio. Once the lightening gets to your radio, it will find a path through it and your house to the electrical service ground. The energy in lightening is very intense and it would certainly destroy your radio in this situation and could easily start a fire in your home.
So what we need to prevent is the lightening from coming into your house through the coax or the radio ground. There are two ways to do this:
1) Disconnect your feed line on the antenna side of the arrestor and more the disconnected coax WELL AWAY from your house or
2) Properly bind the radio/coax ground rod to the electrical system ground at your meter
Doing #2 is difficult because the path that you create via binding must be so much better than the one through your radio/house that lightening will not go there. When I did mine, I used buried 00 gauge cable, avoided any sharp bends, and drop 10 ft ground rods every 6 feet or so and connected those to the bonding cable a it made its way from my radio/coax ground to the house electrical ground.
For a basic station like your, I think that #1 is much easier.
Also, you should properly seal all of your outside connections with coax wrap + electrical tape except the one that you will need to disconnect.
I hope that this helps.
Sounds like a plan. Is the location a potential site for a tower upgrade at a future time? If so, you might what to build your concrete base to Rohn’s specs for 25G or perhaps a 45G tower in the future.
Hi Greg,
FB on your Hex Beam project. This will make a very good antenna system.
A 35 ft mast will certainly need to be guyed at 2 – 3 levels. If you can get guy rings for your mast which will allow the mast to rotate inside the guy rings, then mounting the rotator at the base of the mast on a concrete pad will allow you to service the rotator if you need to. If you do this, you will need some sort of thrust bearing arrangement to take the weight of the mast off the rotator. Without this, the with of the setup will probably cause the rotator to fail at some point. If you put your rotator on the top of the mast, it can probably handle the weight of the text beam without a thrust bearing.
I would be a little careful with trying to use a ladder resting against the mast to service the setup. If the mast is not strong enough and guyed strongly, you’d run the risk of the setup collapsing while you where on the ladder. Can you get a small lift into the area? This may be s safe approach if you can get a lift close and on solid ground.
Don’t forget to include a rotator loop in you coax. Leave enough slack for the antenna to turn its full rotation in both directions without stressing the coax.
One additional thought, you might try to build or purchase a PC interface for the rotator controller. This will make point the antenna at individual stations much easier.