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Marconi testing the Sigma4 vs. Gain Master
- Thread starter Marconi
- Start date
You guys are getting a bit ridiculous...seeking the sublime. This is why science as theorized the isotropic model, and the 6" spring for your 102" stainless steel whip.
Next, you'll all be considering the bird shit on my ground plane radials and maybe even how it affects the interference/cancellation factors of Common Mode Currents on my coax.:glare:
Next, you'll all be considering the bird shit on my ground plane radials and maybe even how it affects the interference/cancellation factors of Common Mode Currents on my coax.:glare:
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i have little doubt that whatever causes it is opening a second path with a variable delay,
the other effects mr suburban mentioned with trucks trains ect we see and use foxhunting, we use passing semis to help determine which direction the fox is, likewise we use obstructions we drive past that dip or picket fence a signal to do the same thing,
i won't hide beside a motorway or major road because they would see the signal dipping as trucks pass and thats a big clue i aint off road,
when hiding we use the lay of the land and obstructions to confuse the hunters
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the effect i think im hearing on eddies vid is a phasey shallowing and thickening of their audio, eddie says he does not hear it live.
the other effects mr suburban mentioned with trucks trains ect we see and use foxhunting, we use passing semis to help determine which direction the fox is, likewise we use obstructions we drive past that dip or picket fence a signal to do the same thing,
i won't hide beside a motorway or major road because they would see the signal dipping as trucks pass and thats a big clue i aint off road,
when hiding we use the lay of the land and obstructions to confuse the hunters
.the effect i think im hearing on eddies vid is a phasey shallowing and thickening of their audio, eddie says he does not hear it live.
OK Mack explain the difference between a am carrier and fm when used to compare signals why is FM better? I wont even bring up the capture effect of the reciever ...Im trying to get my learn on
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i have little doubt that whatever causes it is opening a second path with a variable delay,
the other effects mr suburban mentioned with trucks trains ect we see and use foxhunting, we use passing semis to help determine which direction the fox is, likewise we use obstructions we drive past that dip or picket fence a signal to do the same thing,
i won't hide beside a motorway or major road because they would see the signal dipping as trucks pass and thats a big clue i aint off road,
when hiding we use the lay of the land and obstructions to confuse the hunters
the effect i think im hearing on eddies vid is a phasey shallowing and thickening of their audio, eddie says he does not hear it live.
I wish more people would try that kinda stuff around here. I would enjoy doing some 27 mhz fox hunting.
If you never did that and saw the effect first hand you would be sitting here like other naysayer who cant understand what shit affects signals.
Any stable carrier in the distance (not your signal generator placed to where you get a weak signal) is ideal to compare antennas against. Could be AM, CW, FM, or a few others as long as no modulation or power fluctuation takes place. Using CW as the receive mode is beneficial to reduce any interference. If you have to use a modulated signal, FM is your best choice. SSB is a disaster for comparing small signal changes but will work if the differences are large enough.
Bob, you bring back many memories from the 1980's of CB hide and seek. The Radio Shack metal project box with the loop of RG8U coax that I slit the braid in the center on. My mothers cookie sheet I used for a shield because I could never get the damn whip to work with the loop so it wasn't bi-directional. This worked great to find them.
Tricking them from finding me often meant trying to bounce my signal off the big hospital building in town. It's huge and has tons of metal to reflect off. Being it was on the hill you had line of site to this reflector from many areas. I would try to get below it and back up against other metal objects (aluminum sided buildings were a favorite) to direct the signal towards the building. Even angled the ball mount in an attempt to get some mechanical upward beam tilt. Can't say I never got caught but I'm sure I could do better today.
Bob, you bring back many memories from the 1980's of CB hide and seek. The Radio Shack metal project box with the loop of RG8U coax that I slit the braid in the center on. My mothers cookie sheet I used for a shield because I could never get the damn whip to work with the loop so it wasn't bi-directional. This worked great to find them.
Tricking them from finding me often meant trying to bounce my signal off the big hospital building in town. It's huge and has tons of metal to reflect off. Being it was on the hill you had line of site to this reflector from many areas. I would try to get below it and back up against other metal objects (aluminum sided buildings were a favorite) to direct the signal towards the building. Even angled the ball mount in an attempt to get some mechanical upward beam tilt. Can't say I never got caught but I'm sure I could do better today.
The only strong BC station in my area is 80 MHz away and my low pass filter eliminates them. Me and the station 55 miles away are on the coast and have 90% of the trip over water. I have seen slight changes between tides but nothing like what we are talking about here. The part that confuses me is the huge variation in time that it can take for these long path signals to restabilize.
Sometimes we see shifts in signal that clearly resemble reflections off other moving objects. Where you can see the Doppler effect speed the fluctuation up as it approaches and slow down as it passes. Other times it takes forever for one null and peak to occur. It's been a while since I had an 11 meter horizontal antenna. Although, I recall the effect was sometimes worse to some stations in the same 25 to 55 or more mile range while others could show no signs of this effect.
So no matter who does an antenna test and review it's never gonna satisfy everyone?
That's the way it appears to me so I'm gonna keep my mouth shut if I ever do another.
That's the way it appears to me so I'm gonna keep my mouth shut if I ever do another.
Aw, now, you're takin' all the fun out of it. It seems 3/4 of the interest is tellin' someone how wrong they are. . . :laugh:
Now dont get all huffy Mack, you said FM was better we just asked you to explain yourself. As far as doing tests if your gonna do a test and it is out in open wouldnt you want to have it critique correctly so there are no variables and the test can be repeated by you. There are ways to do a test and there are other ways to do a test. Comparing a apple to a orange is useless. No one is slamming Marconi we are trying to find out why he is seeing what he is. It isn't normal in my mind.
I was talking about Am broadcast/Shortwave that are running kilowatts of power. who would fit under your lo pass filters band pass. Now your changing the whole game by going over water I would expect the signal to flucuate reflecting off the water and I wouldnt expect the water to be still. How high is your antenna? How high do you think you friends is ? Simple explanation could be lo and high tide, 55 miles what is the radio horizon between you ?
This is truely Area 51 stuff perhaps you can film it like marconi, it happens pretty often right. You dont think the squibs over at Groton sub base is fooling with you do ya?
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I wasn't getting huffy, I being polite and not calling you a knit picking asshole.
To me 3/4 of it is getting a accurate test result for others who search the internet for results of how a certain antenna performs. There gonna think using SSB and some of this other stuff is the way to test a antenna. They are gonna think you put the tips of antenna at same height, they are gonna think s meters can show .5 to 1 db of gain. Were just trying to get some honest repeatable results you testing one way and someone else testing another yields different results.
What are some of the thing we have learned?
1) bar graph meters are pretty much just for looks comparing signals Nah.
2) The agc of a meter does have a effect on stronger signals, it wants to equalize them.
3) The sigma and other 5/8 wave's have more gain on horizon testing in close will yield similiar results to 1/4 waves.
4) You will see better results if the test signals are further away.
5) am- fm or cw with a steady output can and should be used.
6) For accurate comparison antennas need to be mounted on same mast in same location with same coax.
7) S meters are different on every radio what you see on yours i dont see same on mine.
8) Vehicles and people can and do have a effect on signals
Now this isnt a knock on Eddie or anyone else it is about getting the correct info. Marconi has been doing these test and will do anything we ask him it seems in a effort to get the correct result as well. I am not trying to boast but I have many many many hours testing antennas trying to get max gain and nothing else
Thats ok if you knew more you would be able to knit pick to, so when do we get that answer about FM vs Am