Anybody Tried This?

Welcome to the forum!

{EDIT: See post #6 below}

Your installation should work just fine. Generally, the length below ground isn't counted against the 3 meter length budget but that is always subject to the interpretation of a FCC inspector. I am not aware of any problems with this though.

That is a very nice thing you are doing for your grandson and it could spark an interest in radio, engineering, and technology. This is coming from someone who started an engineering career playing with radio and Part 15 broadcasting.

Neil

marosborne, your antenna idea is not one I've heard before, and since Neil Radio8Z says it will work, I am hoping that comments get posted about the physics of an antenna that is partly grounded.

I would personally feel secure not counting the buried part of the antenna against the precious 3-meter budget, which would give you either more antenna height or more lead (transmission line) length.

If you build it I hope you return to give a result report.

Well, I haven't heard of trying this but who knows.

There is the case for using a grounded tower as an antenna.  The shield of the coax is connected to the base of the tower.  Elevated radials (ungrounded) which extend out from the base of the tower, equal and opposite in direction, are connected to the center conductor of the coax.

It's all backwards to conventional antenna connections but as noted in the ARRL account it seems to work just fine.  The idea was to allow using the vertical, grounded antenna tower as a radiator for the 160 meter amateur band.

Please let us know the results of your Ground Rod Antenna.

... Does anyone know what kind of results one would get by driving an 8 foot copper ground rod into the ground by about 2 feet... then using a 2 foot wire lead from the back of the transmitter to the ground rod?  ...

I think the i A.M. transmitter is designed for use with the indoor antenna wire they supply, and the "power supply ground" of that system.  The automatic antenna tuner built in to that transmitter may not work very well with other antenna system configurations.

You might try this "stock" configuration first to see if it gives you good results, without the ground rod approach.  If it doesn't do that, please post back for more comments.

Hope you and your grandson will have fun with it.

I did not read the original post carefully enough. I thought you were going to connect the transmitter case to the ground and use an antenna rather than connect the antenna to the ground rod.

Attaching the antenna to the ground rod most likely won't work well, if at all.

Neil

Thanks for the input, guys!  I'm pretty sure that Neil is right, but just for giggles I'll try it this weekend and report back.

Could be compared to carrier current neutral injection.  

After all, in that case the transmitter output is connected to the neutral of the power grid (read ground.)  And the transmitter ground is connected to an isolated ground.

In your case you are connecting the transmitter output to an isolated ground and the transmitter ground to the power grid ground (read neutral.)

Might produce similar results...  After all, Rich maintains rightly so, a ground wire radiates.  But remember the "stock configuration" using the AC ground violates the rule per Rich.

This thread drifted so far off the original topic that it needed some purging.

Please try to stay with the topic at hand, else start a new thread with your thoughts.

Neil

The weekend draws near.  

I am very interested to hear of the results of the ground rod antenna.  It will be interesting to see if "reverse neutral injection" as I've compared it to works.

The Talking House/I A.M. transmitter auto tuner, as Rich noted, may be the proverbial "wrench" in the test.  Perhaps being only a couple feet in the earth will offer a high enough impedance to have little effect.

If Edison had given up, it may have been years before the light came on.

This morning I tested the i.A.M. transmitter as described in my original post at the top of this thread.

The result was slightly improved coverage with the grounded antenna when compared to stringing the stock 10' "indoor" antenna wire vertically outdoors.

I had no signal strength meter to use; only my car radio.  My best guess would be that the RF at about 1/10 mile out may have about doubled.  But -- it's one of those instances where you ask yourself what's 2 times zero?

I will say that I live in an area where ground conductivity is only around 1.0... and that my yard is very "ledgy".  So we're not talking ideal grounding conditions anyway.

I feel strongly that I'll get far better results when I plant my copper ground plane.

marosborne, I find your experiment to be the seed of an idea, but like the two zeros the "idea" is pure imagination... but

Wait, that got too cryptic. I'll start again.

To me, the fact that "the result was slightly improved coverage," could mean, or, might mean, or possibly means that there's an antenna design hidden below the surface.

What it reminds me of is the giant BURIED antenna carrying ELF (Extra Low Frequency) radio transmissions through earth and sea to submerged submarines.

https://en.wikipedia.org/wiki/Extremely_low_frequency

Here's a related link:

https://en.wikipedia.org/wiki/Ground_dipole