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Just installed a 72' end fed and have a few questions.
- Thread starter Low_Boy
- Start date
BJ radionut
Supporting Member and 6m addict
Mt R. The link you posted...OMG finally a Mfg.. stating the EF'ds are a compromise antenna.
Even they suggest minimum 8 radials 20ft long and goes further to say more is better.
To make the a 1/4 wave ground mounted End fed work properly most will tell you 30 Tuned radials is the magic number minimum and up to 120 evenly spaced for length of .12 (1/8th wave).
I have found 4/ radials minimum per band at 5% longer than Quarter wave worked best for me, even if they are elevated.
Yes, do ground the ground post on the UNUN and then tie radials to rod then space them evenly around that point. (even a short 4 ft rod will help)(done this camping and FD operations)
Then wind a choke in the feedline to decouple it from the antenna to stop CMC.
This holds true for random wire set-up also, otherwise where is the other HALF of your antenna? Plus using half of an antenna and transmitting A/C what does that do for your efficiency ?
All the Best
Gary
Even they suggest minimum 8 radials 20ft long and goes further to say more is better.
To make the a 1/4 wave ground mounted End fed work properly most will tell you 30 Tuned radials is the magic number minimum and up to 120 evenly spaced for length of .12 (1/8th wave).
I have found 4/ radials minimum per band at 5% longer than Quarter wave worked best for me, even if they are elevated.
Yes, do ground the ground post on the UNUN and then tie radials to rod then space them evenly around that point. (even a short 4 ft rod will help)(done this camping and FD operations)
Then wind a choke in the feedline to decouple it from the antenna to stop CMC.
This holds true for random wire set-up also, otherwise where is the other HALF of your antenna? Plus using half of an antenna and transmitting A/C what does that do for your efficiency ?
All the Best
Gary
Well after reading Mike's (sp5it ) download a bit over my head but I understand it. And 388_MtRushmore's post a lot simpler and easier for me to understand I am thinking more counterpoise radials will do the trick. Not that this is not working or tuning but I would like to get all bands down below 3:1 before tuning I believe for more efficiency. And I am running this as a sloper. Also I can afford to trim 1 foot off the antenna because my calculation of the tree 75 feet away fell a bit short. but I hate to cut anything because I am not looking to solder the one foot back .
AIdeal: Sloper configuration with one elevated counterpoise is good but several different length counterpoises maybe better. Length of counterpoise should be a minimum of 30-40 feet but not the same length of the antenna wire. Shorter length counterpoise wires can be used of operation is confined to 40m or higher. Any counterpoise should be at least 1 foot above ground running away from or perpendicular to the antenna wire. Do not ground the counterpoise stud when using a counterpoise(s) or radial field. Counterpoise wire(s) close to or laying on the ground will couple and become radials with reduced efficiency. You may also use the unun with no counterpoise or ground if your feedline is at least 25+ feet long. In this configuration the coax shield will act as your counterpoise and there should be no ground at the unun. With this installation there is a high probability of common mode currents on the shield so a good 1:1 choke balun should be installed in the feedline at or near the point it enters your operating position. Good: Attach counterpoise stud to a radial field of 8 wires minimum, each 10 -20 feet long. Again, more is better and will increase efficiency. Longer length radials are not necessary. Workable: Attach counterpoise stud on unun to a good ground rod at or near the feed point of thet least this is what I believe after reading this.
AIdeal: Sloper configuration with one elevated counterpoise is good but several different length counterpoises maybe better. Length of counterpoise should be a minimum of 30-40 feet but not the same length of the antenna wire. Shorter length counterpoise wires can be used of operation is confined to 40m or higher. Any counterpoise should be at least 1 foot above ground running away from or perpendicular to the antenna wire. Do not ground the counterpoise stud when using a counterpoise(s) or radial field. Counterpoise wire(s) close to or laying on the ground will couple and become radials with reduced efficiency. You may also use the unun with no counterpoise or ground if your feedline is at least 25+ feet long. In this configuration the coax shield will act as your counterpoise and there should be no ground at the unun. With this installation there is a high probability of common mode currents on the shield so a good 1:1 choke balun should be installed in the feedline at or near the point it enters your operating position. Good: Attach counterpoise stud to a radial field of 8 wires minimum, each 10 -20 feet long. Again, more is better and will increase efficiency. Longer length radials are not necessary. Workable: Attach counterpoise stud on unun to a good ground rod at or near the feed point of thet least this is what I believe after reading this.
Keep in mind that the link sp5it posted is for a different type of antenna, so most of the details are not the same. You can fold the antenna over on itself to adjust the length and see what it does. There are no exact dimensions for a wire like this so you may have to play with it a little.
That is what I have done so I guess no cutting is involved. GOOD. Sun is out now and stopped snowing so I am going to try a second counterpoise of 40 foot and see if anything changes.
I would like to at least get 40 Mtr. 80 mtr. is so good I can use it with out a tuner. 50 mtr. also. not making much sense. Also adding a second counterpoise did not do much.
I wouldn't expect a whole lot on 80 or 160 just because it is pretty short. I have used a 124' wire, and I wasn't very successful, but the band was dead at the time. All of the stations I could hear were running amps, and most couldn't get a good copy on me.
my 80 meter works great with a 1:8 with counterpoise. 40 meter the match will not come down. My brand new MFJ-986 Tuner is junk right from MFJ not even making contact through the coils. I wish I tested if when first purchased.
80 works great and shows a decent swr. I used it yesterdsy. I takled a good 400 miles away and never realized until todsy the radio was only on 25 watts.
BJ radionut
Supporting Member and 6m addict
Low Boy: What gives you the impression the Roller inductor is not functioning correctly?
Not questioning your wrong because contacts on rollers can be an issue on any of them.
Just what gave you that impression, it may be fixable with a little cleaning or adjustment.
Second: Do you have a good ground on the tuner?
All the Best
Gary
Not questioning your wrong because contacts on rollers can be an issue on any of them.
Just what gave you that impression, it may be fixable with a little cleaning or adjustment.
Second: Do you have a good ground on the tuner?
All the Best
Gary
If I put my ohm meter on the antenna 1 or 2 and the radio input I get no continuity at all. On either Antenna One or antenna two. I do get continuity on bypass one or bypass to and dummy load. For some reason there is no connection between input and .output. I rechecked this with my little tuner and all works well. It may be the switch is hooked up wrong. But it all looks kind of confusing to me. I would like to fix it cuz I hate to send it away.