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(2017-05-22, 21:28)hp3ak2 Wrote: Slowly rotating my 1m crossed loops will null the signal in one channel, while maximizing it in the other channel. I can make either channel very strong while making the other quite weak, or I can make both about equal, but very strong. It does not appear that moving the antennas, within this neighborhood, will do any good at all.
The loops don't *have* to be at 90 degrees. 90 degrees just produces a nice omni directional polar pattern. I have two VLF transimitters within 30 miles one at 285 degrees the other at 260 degrees, these produce huge signals. I have one loop orientated to pickup as little as possible of both transmitters, they aren't equal strength so the null of that loop is not on bearing 272.5 degrees but more towards the stronger. This channel has the LPF set to 54.7 khz (did I say there is also a 60 kHz time signal transmitter co-located with one of the VLF transmitters?)
The other loop has its LPF set to 17.3 kHz (the Tx's are on 19.6 and 22.1 kHz) and rotated away from the first loop such that the levels of the interfering carriers are the same for both channels. This means the angle between the two loops is only about 30 degrees. Yes the polar pattern is severly compromised but if I had the loops at 90 degrees the one "looking" at the transmitters wouldn't see anything other than those transmitters.
Perhaps you could do something similar? How well do you get on with the farmer with fencer? Would they llet you try supressing it? How well maintained is the actual fence? Are all the energised wires well insulated from ground and vegetation kept clear?
As for a guide for gains, thresholds etc, every stations enviroment is different so what works for one probably won't be particulary applicable to another. My station is in "automatic". There is a recomendation to have the first gain figure higher than the second on the settings page, ie use 10 x 8 rather than 8 x 10.
Cheers
Dave.
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how is E-field vs. H-field? More or less? Also, your gain looks pretty high. Mine is broken right now... Lawn mower got the cable to my loops. Will try to fix this week. But, my gain is usually 4x5 or so with a 1 meter 4 turn loops and I routinely participate in strikes in excess of 2000 Km away. Try knocking your gain down a bit and see what the pulses look like and see how much participation you get.
I looked at the satellite pics of where you are, and it looks rural. You are probably on to something with the fencer. Not sure what can be done about that as the output of those is a big spike of short duration. They may easily be 10Kv or higher spikes, and you want to make a lasting impression on whatever gets near the fence without doing anything permanent. As the other poster said, see if you can confirm fencer, and maybe which one. If you can isolate it - verify who's by seeing if you can get it shut for a bit - offer to patrol the fence looking for arcing - hot spot on your radio - and possible vegetation contact. If that might help you and the fence owner.
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(2017-05-23, 01:37)BobW Wrote: how is E-field vs. H-field? More or less? Also, your gain looks pretty high.
I looked at the satellite pics of where you are, and it looks rural. You are probably on to something with the fencer. Not sure what can be done about that as the output of those is a big spike of short duration. They may easily be 10Kv or higher spikes, .....
Some good advice, thanks! System Red and Amplifier 12, so cannot look at the E-field. There are dairy farms and electric fences all around me. The farmers are generally uncooperative, especially with a Gringo like me. The main computers are generally sorting out the false hits, except then the time stamp happens to be very close. It sure hurts my statistics though.
Again, a FAQ on all manual settings and their effect, in one place, would be most helpful. But, like Linux and all things geek, you're just supposed to know this stuff or look it up, piece-by-piece!
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Not having a comprehensive manual is part of the fun. B-) Encourages experimentation, though I must admit it would be nice to have a target range for the noise floor as presented to the ADC's. A lot of settings have a blue "i" that provides some float over help.
Cheers
Dave.
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(2017-05-23, 19:01)allsorts Wrote: Not having a comprehensive manual is part of the fun. B-) Encourages experimentation, though I must admit it would be nice to have a target range for the noise floor as presented to the ADC's. A lot of settings have a blue "i" that provides some float over help.
I now see that I posted this thread in the wrong area of the forum. My apologies.
I will not be reading any more replies here. Thanks to everyone who tried to help!
*** "Welcome to British Experimental Airways. As a passenger we wish to give you the most control of your flight possible. My name is "Automatic", and I am your robotic Captain. I have been programmed to give you an average flight, from an average airport, in average weather conditions, going to an average destination via an average route at an average altitude."
"Since we know that you can probably do better yourself, please note the little steering wheel and various knobs and levers in front of you. You may take control of most functions of the aircraft from your seat. There are clear labels on each control, but if we told you what each one does and how they interact, then where would be the fun in that?
It's a grand experiment! If you are a regular passenger, then you probably have a good idea of what to do to get us all there more quickly and safely. ... Or, you can just leave "Captain Automatic" in charge...trust me! " ***
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"Wrong area of forum"?
So what? I think it's interesting reading for anyone following. I take the labels as general guidance, not law.
You can do e-field testing with your h- field amp. Un wire the loop on one channel - or both - and stick a wire in the inin grounded side of the nput. You may find that e-field holds some hope.
