Bleeder Resistor On Endfed

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ridgescan

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I vaguely recall reading something about someone having attached something of a "bleeder resistor" at the far end of an HF antenna, which went to ground there, to supposedly bleed off static charges on the element. I cannot find that info back, so I'm asking here. I ask this because my 100' endfed wire antenna with the PAR 9:1 box that is already well-grounded at feedpoint, is secured at the far end with an egg insulator, to an aluminum rod secured to a non-metal aerator pipe. But feeling experimental yesterday, I went up there and attached a short ground wire to that rod, and then to a nearby copper grounded aerator pipe. This took some nagging daytime crackels down a bit in MW and cleaned up the HF bands noticeably. What does this mean, and could I do even better by trying that bleeder resistor at the far end being directly attached to the element?
 

bharvey2

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I'm trying to remember where (no luck) but I recall seeing some antenna designs that have a resistor at the far end of horizontal, long wire. It seems like the resistor value was moderate to high. What about trying a variable resistor to ground at the far end and adjust accordingly to see what you get?

Also, have you considered a loop antenna? I've been experimenting with one for HF (xmit and receive) and it is noticeably quieter. I live in a densely populated area of San Leandro and I can't get less that S8 with a 1/2wave end fed wire and S6 or S7 with a dipole. With a magnetic loop I can get as low as S5.
 

ridgescan

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Appreciate the replies. I actually have two HF antennas up there; this wire antenna, and a Wellbrook loop. Being that Wellbrook is up 50' from earth and being active, it's actually noisier than the wire on HF, but is as quiet and a tad more effective in MW due to its directional ability. It should be run close to earth for greater quieting but at my QTH that is not doable.
I went up there today with a 1000ohm resistor and tried it. No discernible difference, but probably the value was too high. I need to dig around my junkboxes to try and find one around 450ohms and do it again.
 

WA8ZTZ

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Beverage and rhombic antennas use a terminating resistor.

Not sure what you mean by "aerator pipe" ??? Are you referring to the vent pipe (part of the drain-waste-vent or DWV system... aka: "stink pipe")? If so, it may not be grounded or may be poorly grounded. In which case you merely added more antenna. ;)
 

ka3jjz

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Appreciate the replies. I actually have two HF antennas up there; this wire antenna, and a Wellbrook loop. Being that Wellbrook is up 50' from earth and being active, it's actually noisier than the wire on HF, but is as quiet and a tad more effective in MW due to its directional ability. It should be run close to earth for greater quieting but at my QTH that is not doable.
I went up there today with a 1000ohm resistor and tried it. No discernible difference, but probably the value was too high. I need to dig around my junkboxes to try and find one around 450ohms and do it again.
Actually, Ridge, you should experiment with your Wellbrook to see if a smaller height would not work better. Loops like this have been known to work very well when mounted close to the ground (and as far away from the home as possible, of course). You will, I think, find somewhere that is quieter than where you have it now. I've seen pics of installations that were just a couple of feet from the ground. You may actually be shooting yourself in the foot having that Wellbrook so high. It sure shouldn't be noisier than the wire - that in and of itself should be a tipoff that something is amiss.

It will take some experimenting to find a quiet spot - there's no good rule here. However, taking an el-cheapo portable radio and wandering in your yard might be a place to start; now, back to the resistor topic....Mike
 

ridgescan

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Beverage and rhombic antennas use a terminating resistor.

Not sure what you mean by "aerator pipe" ??? Are you referring to the vent pipe (part of the drain-waste-vent or DWV system... aka: "stink pipe")? If so, it may not be grounded or may be poorly grounded. In which case you merely added more antenna. ;)
In this 10-unit building, There are the 6" iron "stink pipes" and there are also these copper 3" vent pipes I think for equalizing sinks and tubs. But what I did a couple years ago was I ran my 100' extension chord up there and tested the copper ones for ground and they registered 125v as they were contacted on my multimeter. So I know they're bonded to earth.
Actually, Ridge, you should experiment with your Wellbrook to see if a smaller height would not work better. Loops like this have been known to work very well when mounted close to the ground (and as far away from the home as possible, of course). You will, I think, find somewhere that is quieter than where you have it now. I've seen pics of installations that were just a couple of feet from the ground. You may actually be shooting yourself in the foot having that Wellbrook so high. It sure shouldn't be noisier than the wire - that in and of itself should be a tipoff that something is amiss.

It will take some experimenting to find a quiet spot - there's no good rule here. However, taking an el-cheapo portable radio and wandering in your yard might be a place to start; now, back to the resistor topic....Mike
I have it up on the roof for its security as I am leery about puting it in the commons yard where some smarty could sabotage or steal it. I suppose I could chance it but I paid a lot for that loop and the rotator-it's more secure on the roof. I would love to see how it does down there though. My girl and I are moving next year and I will have a whole private yard to play radios in then:)
 
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