[ARCHIVED THREAD] - Antenna help (Page 1 of 2)
Posted: 12/20/2013 11:06:34 AM EDT
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Okay, I am just getting into HAM. I have a HF rig coming (today in fact), have a general license, but have not had any experience with HAM before. Did CB back in the late 60s early 70 before it took off in popularity, then was on commercial radio back when you needed a license, but HAM is new to me. Here is my back yard:  It is 43' from the neighbor's fence behind me to my house, and about the same running the other direction. I am thinking of an S9V43 antenna:  But of course the best I could do for a ground plane would be 20' radials. Would that be good enough to get me out there? Thanks for any help. |
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What about elevated radials?
I would think a lot of 20' buried radials would work on 30m-10m no problem. 34' is ideal for 40m then they get kinda long after that. You can make them bend at the end with some decreased efficiency but I think if you did say 50 radials you would be fine. |
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Quoted: What about elevated radials? I would think a lot of 20' buried radials would work on 30m-10m no problem. 34' is ideal for 40m then they get kinda long after that. You can make them bend at the end with some decreased efficiency but I think if you did say 50 radials you would be fine. I can make some of them longer (the one at a diagonal), or is it better to go uniform length? |
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About 30 20' radials would do you fine. I have 32 24' radials and no one complains too much when
I'm net control on the digital net. You don't really have to use tuned radials if they're on the ground, so there's some leeway in going shorter. There's a slight efficiency hit but at 20-30 radials it won't be too bad. |
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Quoted: About 30 20' radials would do you fine. I have 32 24' radials and no one complains too much when I'm net control on the digital net. You don't really have to use tuned radials if they're on the ground, so there's some leeway in going shorter. There's a slight efficiency hit but at 20-30 radials it won't be too bad. Is there any better antenna that I might be missing? |
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Quoted:
Thanks. Is there any better antenna that I might be missing? Quoted:
Quoted:
About 30 20' radials would do you fine. I have 32 24' radials and no one complains too much when I'm net control on the digital net. You don't really have to use tuned radials if they're on the ground, so there's some leeway in going shorter. There's a slight efficiency hit but at 20-30 radials it won't be too bad. Is there any better antenna that I might be missing? With your yard size full sized dipoles would be tough. Verticals are great antennas but do tend to be noisy. |
| I like the vertical idea and believe 16 radials is a good start. Can you get a dipole of 120 feet over all length in the front with any height. Tall trees are the best if you have them. Another idea is a loop around the upper level of the house; though, I can't tell how high the peak of the house is from the attached photo. IIRC the shot of the antenna is the stock photo. If you don't yet have a tuner a fan dipole may be the best way to go. 73, Rob |
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Is that an antenna on top of your house now? You could use that for an apex of a dipole or multiband wire type antenna & run legs down toward the spot you have marked. Be easier & cheaper than vertical. That would get you on the air quicker than installing all those radials. With a simple tuner, you can work many bands that way.
HS |
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Quoted: With your yard size full sized dipoles would be tough. Verticals are great antennas but do tend to be noisy. Quoted: Quoted: Quoted: About 30 20' radials would do you fine. I have 32 24' radials and no one complains too much when I'm net control on the digital net. You don't really have to use tuned radials if they're on the ground, so there's some leeway in going shorter. There's a slight efficiency hit but at 20-30 radials it won't be too bad. Is there any better antenna that I might be missing? With your yard size full sized dipoles would be tough. Verticals are great antennas but do tend to be noisy. I am considering something like the Diamond Antenna CP725H Vertical Antenna as a possibility, I guess it might start with something like that. Trouble is, if I do that, then my shack will be in a back room farther from the back yard, and that would make transitioning to something like the other antenna difficult. |
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You don't need a ground plane with a dipole or OCF wire. Just string it up, run coax to your tuner & away you go. Not sure if you have 135' of space available, but my OCF dipole is 44' on one leg & 88' on the other. It will tune & work 80/75, 40, 20, 17, 12, & 10.
HS |
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Quoted: Is that an antenna on top of your house now? You could use that for an apex of a dipole or multiband wire type antenna & run legs down toward the spot you have marked. Be easier & cheaper than vertical. That would get you on the air quicker than installing all those radials. With a simple tuner, you can work many bands that way. HS |
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Quoted:
]Thanks. Is there any better antenna that I might be missing? Verticals are great performers, especially in limited areas. While technically a perfect vertical is inferior to a perfect dipole, in practice few hams put dipoles high enough to approach perfect efficiency, so the performance gap is much smaller, and the radiation angle of verticals is concentrated at lower angles making them very well suited for longer distance (500+ mile) work. I've tried many, many antennas and with my constraints (no trees or towers that can get an antenna above 35' or so) the 43' vertical has out-performed everything else I've tried. |
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I see trees, and every ham knows God invented them to be used for antenna supports.
Get some wire and ladder line and toss one cut for 80 Meters where you show the OCF Dipole. It will require a simple tuner (such as the MFJ-941E) with balanced output and will cover 80 Meters and above. I think you will be very pleasantly surprised. Here's one good source for antenna materials: http://www.thewireman.com/ |
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Quoted: I see trees, and every ham knows God invented them to be used for antenna supports. Get some wire and ladder line and toss one cut for 80 Meters where you show the OCF Dipole. It will require a simple tuner with balanced output. I think you will be very pleasantly surprised. Here's one good source for antenna materials: http://www.thewireman.com/ |
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I've operated 100 Watts using insulated wire through Pine and Magnolia trees without any problems. I've also done it with uninsulated wire, but the tuning gets a little flaky when it rains or snows.
Here's a sturdy center insulator for ladder line: http://www.aesham.com/index.php?p=catalog&mode=search&search_in=all&search_str=ladder-loc End insulators: http://www.aesham.com/wire/alpha-delta-delta-cin/ |
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It is to the back of my house, with the top about even with the apex of the roof. But I could always throw up another pole no problem. Quoted:
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Ah ha, the question now is,"How tall above the roof is the TV antenna mast?" 73, Rob If strong enough, the antenna will actually help guy the pole. I still recommend a ladder line fed dipole, using a tuner with low loss feed line will work all bands from the lowest frequency the dipole is cut for up to 10M or 6 Meters depending upon the tuner. The guys running an OCFD with a rig having an internal tuner need to report in on this one. 73, Rob |
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Quoted: If strong enough, the antenna will actually help guy the pole. I still recommend a ladder line fed dipole, using a tuner with low loss feed line will work all bands from the lowest frequency the dipole is cut for up to 10M or 6 Meters depending upon the tuner. The guys running an OCFD with a rig having an internal tuner need to report in on this one. 73, Rob Quoted: Quoted: Quoted: Ah ha, the question now is,"How tall above the roof is the TV antenna mast?" 73, Rob If strong enough, the antenna will actually help guy the pole. I still recommend a ladder line fed dipole, using a tuner with low loss feed line will work all bands from the lowest frequency the dipole is cut for up to 10M or 6 Meters depending upon the tuner. The guys running an OCFD with a rig having an internal tuner need to report in on this one. 73, Rob |
| The correct answer is "get both". The vertical will be great for DX and longer distance contacts. The dipole/OCFD or other wire antenna off the roof will be good for NVIS (close-in) contacts. You will have the advantage to switch between the two if need arises. OCFD's and wire antennas in general are cheap to make, so if you have the $$$, put up the 43ft vertical with SGC auto-tuner and the dipole. |
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You want to keep the ends of the wires, where the voltage is highest (current is highest in the middle, voltage at the ends) clear of the trees, especially when very dry, and especially running an amp. "I'll switch on my amp and put a little fire in the wire," had some real meaning for one of my friends.
I like this insulator for dipoles and coax. http://www.universal-radio.com/catalog/antsup/5524.html I used to use porcelain end insulators, but lately I've been using these, and they work fine. http://www.universal-radio.com/catalog/antsup/4818.html Here's a dipole kit. http://www.universal-radio.com/catalog/antsup/0297.html The only center fed dipole that will tune on another ham band (with tuner) is a 40 meter (7 mhz) dipole which will also work on 15 meters (3 x 7 mhz = 21 mhz). For an OCFD you need a 4:1 current balun (not voltage balun) at the feedpoint. The OCFD at the club station has the legs at 135 degrees, not 180, and it works as it should. For 40 meters, 20 m, 17, 15, 10 m, an OCFD with 4:1 current balun and 53' one side, 13' on the other, will work these bands with a tuner. Two other popular splits, 44' + 22' will give the most even SWR on 40, 20, 10 meters, but will not work 15 m. 41' + 25' will work 17 and 15 m with tuner. For 80 meters, 40, 20, 17, 15, 10 m, OCFD with 4:1 current balun, 95' + 39' will do all these bands. 88' + 44' will give most even SWR from band to band, but will not work 15 m, no matter how good your tuner. 82' + 50' will work 15 m. |
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Quoted:
The correct answer is "get both". The vertical will be great for DX and longer distance contacts. The dipole/OCFD or other wire antenna off the roof will be good for NVIS (close-in) contacts. You will have the advantage to switch between the two if need arises. OCFD's and wire antennas in general are cheap to make, so if you have the $$$, put up the 43ft vertical with SGC auto-tuner and the dipole. One reason to build more than one antenna is that they cover different bands. But sometimes, even on the same bands, one type of antenna will receive a signal stronger, or with less noise, than another. |
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Quoted: You want to keep the ends of the wires, where the voltage is highest (current is highest in the middle, voltage at the ends) clear of the trees, especially when very dry, and especially running an amp. "I'll switch on my amp and put a little fire in the wire," had some real meaning for one of my friends. I like this insulator for dipoles and coax. http://www.universal-radio.com/catalog/antsup/5524.html I used to use porcelain end insulators, but lately I've been using these, and they work fine. http://www.universal-radio.com/catalog/antsup/4818.html Here's a dipole kit. http://www.universal-radio.com/catalog/antsup/0297.html The only center fed dipole that will tune on another ham band (with tuner) is a 40 meter (7 mhz) dipole which will also work on 15 meters (3 x 7 mhz = 21 mhz). For an OCFD you need a 4:1 current balun (not voltage balun) at the feedpoint. The OCFD at the club station has the legs at 135 degrees, not 180, and it works as it should. For 40 meters, 20 m, 17, 15, 10 m, an OCFD with 4:1 current balun and 53' one side, 13' on the other, will work these bands with a tuner. Two other popular splits, 44' + 22' will give the most even SWR on 40, 20, 10 meters, but will not work 15 m. 41' + 25' will work 17 and 15 m with tuner. For 80 meters, 40, 20, 17, 15, 10 m, OCFD with 4:1 current balun, 95' + 39' will do all these bands. 88' + 44' will give most even SWR from band to band, but will not work 15 m, no matter how good your tuner. 82' + 50' will work 15 m. Thank you, great information. The problem I see is that the two biggest trees on my side yard are palm trees. They sway an awful lot in the wind, and there are other lower trees along the run between the two tall trees. I assume that the wire should be "straight" line between the two points? Or is it possible to make a V, going from tree to peak of house to tree. Like this:  Certainly down the road, I will get a vertical as well, I have a feeling that only one antenna is not common. |
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too late to suggest a ladder line fed loop? Don't even measure for resonance, or whatever. Just get as much up there as possible, and then measure the length and work from there.
I've had best luck when the loop is 1.25 waves long on 40m using as a multiband antenna arranged in absurd fashion. |
A) this is ARFCOM. Get both. 
B) getting started with some form of wire antenna will get you on the air TODAY. You're getting a radio, don't you want to use it? Plus trying all the suggestions above is a really good start to experimenting, any one of them might do what you want until you decide you want more. |
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Quoted: too late to suggest a ladder line fed loop? Don't even measure for resonance, or whatever. Just get as much up there as possible, and then measure the length and work from there. I've had best luck when the loop is 1.25 waves long on 40m using as a multiband antenna arranged in absurd fashion. Right now, it looks like I will try a ladder line fed dipole, from tree to house to tree, but there is a lot to work out. I will have to look into this loop set-up. Trouble is, right now I have no idea what bands I am interested in, as I am totally new to HAM. |
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Not even too late. I will not be getting an antenna until next year (two weeks or so) and am just trying to work out all the details before I start messing around. Right now, it looks like I will try a ladder line fed dipole, from tree to house to tree, but there is a lot to work out. I will have to look into this loop set-up. Trouble is, right now I have no idea what bands I am interested in, as I am totally new to HAM. Quoted:
Quoted:
too late to suggest a ladder line fed loop? Don't even measure for resonance, or whatever. Just get as much up there as possible, and then measure the length and work from there. I've had best luck when the loop is 1.25 waves long on 40m using as a multiband antenna arranged in absurd fashion. Right now, it looks like I will try a ladder line fed dipole, from tree to house to tree, but there is a lot to work out. I will have to look into this loop set-up. Trouble is, right now I have no idea what bands I am interested in, as I am totally new to HAM. Let me help. 20m first, then 40m. You're welcome. ETA: You could spend the first year of operating on 20m and never get bored, unless it's winter and you can only operate late at night. |
Unless you go the ladder line dipole route, you're probably going to have to do some trimming. A pair of split bolt connectors saves a lot of twisting and untwisting the wire. After you're satisfied with the match, you can go ahead and twist and solder the ends and save the split bolts for the next antenna. And if you're a real ham, there WILL be a next antenna!
Your local electrical supply house should carry them. |
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Quoted: Let me help. 20m first, then 40m. You're welcome. ETA: You could spend the first year of operating on 20m and never get bored, unless it's winter and you can only operate late at night. Quoted: Let me help. 20m first, then 40m. You're welcome. ETA: You could spend the first year of operating on 20m and never get bored, unless it's winter and you can only operate late at night. Unless you go the ladder line dipole route, you're probably going to have to do some trimming. A pair of split bolt connectors saves a lot of twisting and untwisting the wire. |
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Quoted:
Thank you, great information. The problem I see is that the two biggest trees on my side yard are palm trees. They sway an awful lot in the wind, and there are other lower trees along the run between the two tall trees. I assume that the wire should be "straight" line between the two points? Or is it possible to make a V, going from tree to peak of house to tree. Like this:
Certainly down the road, I will get a vertical as well, I have a feeling that only one antenna is not common. Quoted:
The OCFD at the club station has the legs at 135 degrees, not 180, and it works as it should. Thank you, great information. The problem I see is that the two biggest trees on my side yard are palm trees. They sway an awful lot in the wind, and there are other lower trees along the run between the two tall trees. I assume that the wire should be "straight" line between the two points? Or is it possible to make a V, going from tree to peak of house to tree. Like this:
Certainly down the road, I will get a vertical as well, I have a feeling that only one antenna is not common. Not a problem at all, as I stated. Ours is angled more than you show in your sketch. This is true whether an OCFD or a plain dipole. Angling it on the horizontal plane will add some directionality. Angling it in the vertical plane, and "inverted V", will give it a tad less vertical radiation and a little more horizontal radiation. I doubt any of us would notice. |
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Got it, makes sense. Quoted:
Unless you go the ladder line dipole route, you're probably going to have to do some trimming. A pair of split bolt connectors saves a lot of twisting and untwisting the wire.
Get some of these, about 3x as many as you think you'll need. I wish I had some. 
Using these is better than soldering as you can adjust things, and if the line breaks you can just undo it, and either splice or move then end in or whatever. My main antenna would really benefit from about half a dozen of them right now. Also, someone above mentioned a loop. One of the most entertaining Field Days I had (I haven't participate in many) was one where we put up an 80m full wave loop about 20-35ft. It worked amazing, was really quiet on receive and had a crushing signal at 100w. To this day I still want to try and get a 20m or 40m loop up to see if it was just a fluke. |
| I thought building a dipole would be easy and while putting one up still looks easy, theres a lot of variables to take in. I'm in the same boat you are OP. Im new to HF and should have a radio on the way before the end of the year, so I'm doing my homework on antennas before it gets here. |
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Quoted: I thought building a dipole would be easy and while putting one up still looks easy, theres a lot of variables to take in. I'm in the same boat you are OP. Im new to HF and should have a radio on the way before the end of the year, so I'm doing my homework on antennas before it gets here. I think, I might be leaning toward the Hy power OCF 80 meter. Gotta do some measurements to see it if will fit. |
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That's the fun of it, learning. I think, I might be leaning toward the Hy power OCF 80 meter. Gotta do some measurements to see it if will fit. Quoted:
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I thought building a dipole would be easy and while putting one up still looks easy, theres a lot of variables to take in. I'm in the same boat you are OP. Im new to HF and should have a radio on the way before the end of the year, so I'm doing my homework on antennas before it gets here. I think, I might be leaning toward the Hy power OCF 80 meter. Gotta do some measurements to see it if will fit. Here is the balun you want. Then 90' of wire on one side 45' on the other. That will get you on 80m-6m with an antenna tuner. Obviously keep the wires long and tune as necessary. |
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Quoted:
That's the fun of it, learning. I think, I might be leaning toward the Hy power OCF 80 meter. Gotta do some measurements to see it if will fit. Quoted:
Quoted:
I thought building a dipole would be easy and while putting one up still looks easy, theres a lot of variables to take in. I'm in the same boat you are OP. Im new to HF and should have a radio on the way before the end of the year, so I'm doing my homework on antennas before it gets here. I think, I might be leaning toward the Hy power OCF 80 meter. Gotta do some measurements to see it if will fit. I actually enjoy DIY projects and spend a lot of time researching them. I just for some reason thought an antenna was going to be a no brainer. Now im researching building a balun and trying to figure out what the best arrangement is for my yard. |
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Quoted: Here is the balun you want. Then 90' of wire on one side 45' on the other. That will get you on 80m-6m with an antenna tuner. Obviously keep the wires long and tune as necessary. Quoted: Quoted: Quoted: I thought building a dipole would be easy and while putting one up still looks easy, theres a lot of variables to take in. I'm in the same boat you are OP. Im new to HF and should have a radio on the way before the end of the year, so I'm doing my homework on antennas before it gets here. I think, I might be leaning toward the Hy power OCF 80 meter. Gotta do some measurements to see it if will fit. Here is the balun you want. Then 90' of wire on one side 45' on the other. That will get you on 80m-6m with an antenna tuner. Obviously keep the wires long and tune as necessary. Have to do the measurements to see if it fits! |
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Okay, I know I am being a pain, but you guys have helped me tremendously so far. I did some measurements, and this is what I got:  This puts the antenna feed point close to where the shack will be (close to just below antenna feed point). Problem is, of course, if I want a 45' and 90' run, I got problems. I think a run to the smaller palm tree in the front would work, but it is not tall enough to "see" over my roof peak to make a run without the wire. So, my question is, if I run the wires as shown, then end the 90' with a dog leg over to the "not tall" palm, would that negate the 90' run for what the antenna sees? Also, I currently have a TV antenna on the top of the pole attached to my house where I show the two leg connecting. I know that most of the tx power will be coming from this low voltage area of the dipole, so what should be the minimum distance to the TV antenna (should be able to add a bit more pole length to get the peak of the dipole up a bit higher, but can't go much higher)? |
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You're not being a pain. We love doing problem solving stuff. It's the nature of ham radio.
Dipoles can deviate somewhat from a straight line. For instance, attic dipoles are often run along the ridge of the roof and each end brought down along rafters so when viewed from above the antennas looks somewhat like the letter "Z". The Moxon Antenna carries this concept further, adding a reflector and making it into a beam. Something to consider: The ARRL Antenna Book. It contains a wealth of information on skywires and beams, both in theory and construction projects. |
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Quoted: You're not being a pain. We love doing problem solving stuff. It's the nature of ham radio. Dipoles can deviate somewhat from a straight line. For instance, attic dipoles are often run along the ridge of the roof and each end brought down along rafters so when viewed from above the antennas looks somewhat like the letter "Z". The Moxon Antenna carries this concept further, adding a reflector and making it into a beam. Something to consider: The ARRL Antenna Book. It contains a wealth of information on skywires and beams, both in theory and construction projects.  |
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Quoted: The answer is yes on the dog leg. Don't worry if it's tight (better that it isn't) or if it's straight, or if it even makese sense!!! Get the wire in the air! It WILL work. And if you're doing the large OC like that it will probably work well. Sounds good. Any idea of how close the antenna feed can get to the TV antenna without problems? |
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Quoted:
Sounds good. Any idea of how close the antenna feed can get to the TV antenna without problems? Quoted:
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The answer is yes on the dog leg. Don't worry if it's tight (better that it isn't) or if it's straight, or if it even makese sense!!! Get the wire in the air! It WILL work. And if you're doing the large OC like that it will probably work well. Sounds good. Any idea of how close the antenna feed can get to the TV antenna without problems? No.... that one will be trial and error I'm afraid. ETA: One of the biggest things I'd worry about there is de-sense on the TV when transmitting. Someone must have some better info on this. |
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Quoted:
Okay, I know I am being a pain, but you guys have helped me tremendously so far. I did some measurements, and this is what I got:
This puts the antenna feed point close to where the shack will be (close to just below antenna feed point). Problem is, of course, if I want a 45' and 90' run, I got problems. I think a run to the smaller palm tree in the front would work, but it is not tall enough to "see" over my roof peak to make a run without the wire. So, my question is, if I run the wires as shown, then end the 90' with a dog leg over to the "not tall" palm, would that negate the 90' run for what the antenna sees? Also, I currently have a TV antenna on the top of the pole attached to my house where I show the two leg connecting. I know that most of the tx power will be coming from this low voltage area of the dipole, so what should be the minimum distance to the TV antenna (should be able to add a bit more pole length to get the peak of the dipole up a bit higher, but can't go much higher)? OK, the 44' + 88' split (or 45' + 90') would be a little tight here. But you can use the 50' + 82' split, gain back use of 15 meters. At first it appears you don't have enough length, but you can let the ends hang down. Read here: http://www.buxcomm.com/windom.htm 
So, there's your solution. And with a tuner, 80, 40, 20, 17, 15, 10 meters. What's not to like? |
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Quoted: OK, the 44' + 88' split (or 45' + 90') would be a little tight here. But you can use the 50' + 82' split, gain back use of 15 meters. At first it appears you don't have enough length, but you can let the ends hang down. Read here: http://www.buxcomm.com/windom.htm http://www.buxcomm.com/img5.gif So, there's your solution. And with a tuner, 80, 40, 20, 17, 15, 10 meters. What's not to like? Quoted: Quoted: Okay, I know I am being a pain, but you guys have helped me tremendously so far. I did some measurements, and this is what I got: http://i247.photobucket.com/albums/gg144/Dr_Dickie/MyHouse-2-antenna_zpsf3edc23f.png This puts the antenna feed point close to where the shack will be (close to just below antenna feed point). Problem is, of course, if I want a 45' and 90' run, I got problems. I think a run to the smaller palm tree in the front would work, but it is not tall enough to "see" over my roof peak to make a run without the wire. So, my question is, if I run the wires as shown, then end the 90' with a dog leg over to the "not tall" palm, would that negate the 90' run for what the antenna sees? Also, I currently have a TV antenna on the top of the pole attached to my house where I show the two leg connecting. I know that most of the tx power will be coming from this low voltage area of the dipole, so what should be the minimum distance to the TV antenna (should be able to add a bit more pole length to get the peak of the dipole up a bit higher, but can't go much higher)? OK, the 44' + 88' split (or 45' + 90') would be a little tight here. But you can use the 50' + 82' split, gain back use of 15 meters. At first it appears you don't have enough length, but you can let the ends hang down. Read here: http://www.buxcomm.com/windom.htm http://www.buxcomm.com/img5.gif So, there's your solution. And with a tuner, 80, 40, 20, 17, 15, 10 meters. What's not to like? |
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Most importantly, get the feed point of the dipole up in the air. That's where the current lobes are that do the work. The ends can come down with no problem. For an off center fed dipole run coax as a feed line. R.F. chokes and grounding will take care of any R.F. in the shack problems.
73, Rob |
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Quoted:
34' is ideal for 40m Quoted:
34' is ideal for 40m Incorrect, radials on the surface or just barely subsurface for 40 meters should be about (IIRC) 21 to 22 feet, for average soil. Highly conductive soil would lengthen the radials a little, poorly conductive soils would shorten a little from that figure. The radials being right on the soil causes them to resonate at a much lower frequency due to dielectric effect so to get them correctly tuned they need to be much shorter than the free space wavelength. The more radials you have the less important it is that they are tuned to the band in use and the more acceptable it is to use overly long radials. From my recollection of the information I read (I've posted the link a couple times, but it's dense reading), what looked like a pretty good performance compromise for a multiband antenna would be something like 8 radials at the lowest frequency (say 40m), and 8 more at the next lowest (say 20m), the higher frequencies should be ok then also. If you don't have room for the appropriately scaled 80m radials, and you have an 80/40/20+ vertical, I'd probably just do 8-40 + 8-20 and let the rest fall where they may. Quoted:
You don't really have to use tuned radials if they're on the ground, so there's some leeway in going shorter. There's a slight efficiency hit but at 20-30 radials it won't be too bad. If I'm remembering correctly, the difference between tuned and untuned ground mounted radials could be as much as 6dB or a little more, that's pretty substantial. 8 tuned radials would outperform a pretty significant number of untuned ones. |