you have 45 minutes....

That would have been great. I've worked with the other stuff before on furnace repairs, and it "sets up" way too fast. Thanks.

Did you get better reception with the 45degree backwards lean?

Don't know. Never tried it. The driven elements were always going to be fastened to the screens, exactly as they are, 4 inches in front. I was toying with attaching the "ladder" to the base differently -- to the sides of the base instead of the front. No difference in performance. Just style.

Using a simpler design or not building it completely (or rods instead of screens) would have let me change parameters easily. But drilling lots of holes and making all different lengths of plastic pipe amounts to "re-inventing" the LEGO (tm) concept. And it only took me 35 hours to figure that out. I'm clearly not a rocket scientist!

If you want to make mods easily, build it out of wood.

REMEMBER: 1. Preserve Nature. 2. Always wear a helmet.
3. Ride safely. 4. Read owners manual carefully before riding.

Yeah, I know what you mean about thinking about it a lot. Im in the process of building an outdoor version of the SBGH using only a 7' length of 1" sch 40 pvc (the thick wall stuff), 6 tees, and a cap and some 3/8" spex tubing(for the 20mm reflector gap). And the 3/8 " aluminum rods and 4mm aluminum wire (which is 8 to 9 gauge I believe) for the reflectors and elements. Working time is essential to get everything perfectly aligned and squared. And so is pre-testing the fit of everything.

Right now I only have the means to test it with analog, so my results will be subjective.

http://img.photobucket.com/albums/v350/ericball/102_6928.jpg
Here's my quick & dirty SBGH. The only thing I had to buy was some 12ga hanger wire (steel, but magnetic) from HD. The rest is just a piece of scrap 2x4, a large carboard box, and some aluminum foil. The wire isn't even bent that precisely, when I make the real one (if I can find some large gauge aluminum) I'll draw out a template as suggested.

The following is through a second floor south-facing window in east Markham, Ontario versus a Silver Sensor clone:

ch SS GH
5 0 0
9 2 3
15 - 0+
17 4 4
19 0 4
23 3 4
25 4 4
26 - 2
29 3 3
36 3 4
47 1 3
49 3 3
57 4 4
69 4 5

0 no audio, rolling picture, etc
1 too much snow to watch
2 very snow
3 some snow or ghosting, watchable
4 acceptable
5 crystal clear (like that's OTA, wow!)

I don't even have a clear line of sight as there's a row of 3 story houses less than 100 feet away. Sorry, no DT measurements (yet).

For those of you who have made the transition, what kind of reception can I expect (especially the Buffalo stations)?

I figure a better build will give me a couble more dB, so then the question is where to mount it. I can easily put it on the outside of the house (but still on the 2nd floor) or I can put it in the attic. Which would be better? Any significant difference between the two options? (Attic might be preferable since I don't have to weather proof & ground it.)

I thought I'd give making a version of the single bay Hooverman a try last night.
http://farm3.static.flickr.com/2256/2410648006_5bc788ff6c.jpg
I have it temporarily mounted on a light stand about 8 ft up in the air at the top.

When I went searching for materials last week, here in Meridian, MS basically all I have is a Lowe's which is similar to Home Depot. Knowing very little about the different kinds of wire I got two 1/8" x 48" steel rods made for welding stuff with. I bent it into 8" segments before I studied the actual dimensions of the plans for one. I missed them and went by eyeballing and guessing from other photos. Even so it pulls in all the SD and HD local channels great in it's temporary mount. Going higher off the ground may pull more I hope.

Anyway, I wondered how critical it is to get the dimensions exactly the same as the SBGH plan? If I can't find the exact wire material dimensions as the plan is okay to scale it up/down keeping the proportions the same as plan? Is this steel wire okay? If I get all the parts assembled would giving it a Rustoleum paint job to stave off rusting hurt reception?

Also since I'm a total novice, what's the best way to ground from lightning strikes? My dad had in the past on this house an old VHF/UHF monster that was destroyed in Hurricane Katrina. I still have the pole for it that is okay and around 25ft tall, but all the wiring and grounding that went with the old antenna is long gone. At Lowe's and my local Radio Shack no one seemed to be able to give me an answer on what wire to use or how to ground one. The Lowe's store here is the only one that has any outside antennas for sale, big VHF/UHF ones at that, but no kit that says grounding wire and the sales people are clueless.

I still have the old mangled elements and the square, tubular frame of the defunct VHF/UHF antenna which I thought I would use part of to make a more permanent mount for my Hooverman once I get a chopping board to table-saw into those nifty support attachments. I think that will obviously make it handle any high wind 25ft in the air better than the wood plank. But if I put this thing up I need to know how to ground it. We get lightning on top of the hurricanes and tornadoes...

Thanks in advance.

I thought I'd give making a version of the single bay Hooverman a try last night.Elvis Gump

Your pic shows a Hoverman Array-only without any horizontal stubs.
You may be happy with the results, but the model results indicate that it will have very poor reception.

The GH (Single and Double) antenna has been designed for the post Feb 09 UHF bandwidth of 470 to 700 Mhz [Ch14-50] and the importance of the Array's horizontal stubs in achieving that bandwidth is clearly shown below in the Net gain comparison plot.

Net Gain SBGH 6 Pair vs Array-Only ( with and without Horizontal Stubs)

http://i258.photobucket.com/albums/hh262/autofils/SBGHGPLv3-vs-ArrayOnly.gif

I would suggest that you build to the GPLv3 specs for the SBGH 6 Pair collinear reflectors.


I leave it to other members to provide guidance for your other queries.

...autofils

The reason I omitted them were two-fold, or perhaps three fold. I was desperate to get any signal at all over this past weekend to try to pull in my PBS station, that I didn't find the exact dimension diagram till after I started bending and that I had trouble finding any kind of wire in copper or aluminum that wasn't braided in insulators on a spool at my sole hardware source of Lowe's. As is the thing is pulling in stations in the 40-mile radius which is about all I have. The next closest stations are from 80 to 120 miles+. I don't know if it's going to get any of them properly engineered. I'm such a novice at this as it is.

I'd like to make it out of aluminum or copper to make it rustproof which this being steel welding rods aren't.

Thanks from everyone on the grounding thing. I'm about to make a run to town (I live in the sticks in Mississippi) so I'll forage for the grounding stuff. The wire for the elements though may still be a bit trickier to come by.

Eraser88, the first thing to expect is that you have a 50/50 chance of getting the antennas in phase. If the results don't look good on your first try, just switch the leads on one of the antennas's baluns and test again.

As for your VHF stations, are you close to them? Proximity can make almost any antenna behave in unexpected ways. ;)

till after I started bending and that I had trouble finding any kind of wire in copper or aluminum that wasn't braided in insulators on a spool at my sole hardware source of Lowe's. My Lowes has solid copper wire in 6 and 8 gauge, so double check with the clerk. Its pricey, $1.09 a foot or so, but sometimes they have discounted cut pieces. Also check their plumbing section to see if they 1/8 inch copper tubing.

Also check with the clerk at Lowes or Radio Shack for solid aluminum grounding wire (I think its 8 gauge). Its cheaper and you may luck out if you ask.

Also I find that old hardware stores that have been in business for 50 years are a good source to find unusual solid wire. And you could try an electrical wholesale house, check the yellow pages.

and the importance of the Array's horizontal stubs in achieving that bandwidth is clearly shown below in the Net gain comparison plot.Wow, it sure does.

Would increasing the length of the horizontal stubs increase the channel 14 - 17 gain ? (realizing it would be at the expense of the top end channels)

Seems to me that this thread has become so long and involved that it would be a good idea to create a new page (somewhere, not necessarily a new thread, not necessarily here) that could be used to place all the most pertinent information, graphs, plans, proposed modifications, updates, etc. for the GH.

This thread is going to get more and more questions from people who newly find it and aren't willing or simply haven't read all of the 18 pages and 266+ messages. I think this thread will and should be left as the "round table" of discussion, but it would be good to have one spot to go to for the relevant data and updates to the project work. The http://www.digitalhome.ca/ota/superantenna/design.htm page might be a good place to put these updates and proposed updates, but maybe not.

Of course, I am sure someone has already thought of this, but if it exists I haven't found it.

Just a suggestion. Thanks again for all the effort on this project!:rolleyes:

Wow, it sure does.

Would increasing the length of the horizontal stubs increase the channel 14 - 17 gain ? (realizing it would be at the expense of the top end channels)

the horizontal stubs seems to control the bandwidth of the region somewhat. to shift this to a lower frequency, you would increase the legs of the sqaures and then fiddle with the horizontal stub to get coverage to 700mhz. however, its pretty good already so it seems pointless to mess with this.

another more likely avenue would be to consider larger (as far as diameter) elements which should increase the bandwidth by lowering the swr. some quick simulations this morning showed that awg#6 (4.11mm diameter) would have a better swr, but the feedgap would need to be changed to get the impedance match right.

My Lowes has solid copper wire in 6 and 8 gauge, so double check with the clerk. Its pricey, $1.09 a foot or so, but sometimes they have discounted cut pieces. Also check their plumbing section to see if they 1/8 inch copper tubing.

I didn't think of that. Wouldn't that be some really rare tiny tubing? Or is that the stuff that they plumb ice-makers with?

Also check with the clerk at Lowes or Radio Shack for solid aluminum grounding wire (I think its 8 gauge). Its cheaper and you may luck out if you ask.

I tried Lowe's again yesterday, but all they had was some copper and they weren't terribly helpful other than selling me a grounding block. The fellow I dealt with going back yesterday was very friendly, but also seemed more interested in telling me shortwave radio stuff that went over my head. He was marginally better than the teenage girl the helped me the last time I went in, but as far as I can tell my Lowe's caters to contractors more than they do hobbyist nerds. Under the smiling helpfulness I sensed a certain 'drop dead' vibe whenever I need to ask a question in there.

Also I find that old hardware stores that have been in business for 50 years are a good source to find unusual solid wire. And you could try an electrical wholesale house, check the yellow pages.

Yeah, if there is such a store here I'm going to have to hunt for it. Basically between Wal-Mart and Lowe's most mom and pop kinda places with a dusty back-room with oddball things have all been driven to extinction. And this is Mississippi where they look at me describe what I'm doing with a Republican suspicion that I'm actually shopping for bombmaking components or something, like "who the hell builds their own tv antenna?"

There's an electric supply place I'm going to try, in fact I need to run if I'm going to catch them open today.

Or is that the stuff that they plumb ice-makers with?

Most old icemakers were done with the 1/4 inch id copper stuff , which is even better, bandwidth wise. (most new installations use plastic of course, no good for an antenna) The 1/8 in id copper stuff was/is used in pressure switch type applications or even in window air conditioners for the thermostat. The 1/4 in id copper tubing may even be cheaper per ft than the solid copper wire, if found in the right place. As long as its not kinked, its pretty easy to straighten on a flat board and wooden mallet.

He was marginally better than the teenage girl the helped me the last time I went in, but as far as I can tell my Lowe's caters to contractors more than they do hobbyist nerds. Under the smiling helpfulness I sensed a certain 'drop dead' vibe whenever I need to ask a question in there.


Same with my Lowes here. You just have to find the right clerk who's been there a while. Contractors dont always get good info/help either.

There's an electric supply place I'm going to try, in fact I need to run if I'm going to catch them open today.

Also you could try in rural areas, a farm supply place, like Central Tractor, or if still available in your area, a Southern States Co-op. They may have the thick solid aluminum cow fencing electric wire.

Built from 2 lengths of plastic covered steel garden stakes from Canadian Tire, Styrofoam from a new computer case and oven pans from dollarama and some gorilla glue. Works better than the 4 bay bow tie it replaced.

http://img255.imageshack.us/img255/1839/grayhovermanod4.th.jpg (http://img255.imageshack.us/my.php?image=grayhovermanod4.jpg)

Most old icemakers were done with the 1/4 inch id copper stuff , which is even better, bandwidth wise. (most new installations use plastic of course, no good for an antenna) The 1/8 in id copper stuff was/is used in pressure switch type applications or even in window air conditioners for the thermostat. The 1/4 in id copper tubing may even be cheaper per ft than the solid copper wire, if found in the right place. As long as its not kinked, its pretty easy to straighten on a flat board and wooden mallet.

I have access to a pipe bender, in fact I helped my brother bend some brake lines I think they were for his car which sound sort of the same size as the piping you are describing, though we didn't make anything close to 90 bends. Around the time we were doing that I saw a thing on History or Discovery channel where they were showing how they bend brass piping in trumpets by filling them with freezing water then bend them to lessen the chance of a kink, though I don't know how I'd get a long tube run into my freezer compartment to freeze it!

Same with my Lowes here. You just have to find the right clerk who's been there a while. Contractors dont always get good info/help either.

The Lowe's guy I got yesterday was very pleasant, seemed to know a lot about short wave radios, but didn't have any wire that would work. All the stuff they had seemed to be on rolls that were for contractors and priced $50 and up.

I did try an electric supply place today that just looked at me like I grew a third head when I asked for #9 aluminum wire. I took my laptop with me and showed him the diagrams of the Hooverman and he offered me some copper stuff, I think it's 8-gauge copper. The invoice is a tad hard to make heads or tails off, but I think it was 36-cents a foot, so I got 20 feet which was a little over $7. Since I do live on a farm, I have some older electric fence wire which is a bit smaller in diameter and doesn't look like it would hold it's shape like the copper stuff.

http://farm4.static.flickr.com/3232/2417025803_6ffd58c255.jpg
That's the electric fencing wire on top, it's silvery and might be be steel I guess, the stuff below is the copper which seems a tad thicker.

Neither of these wires are as nice and stiff as my temporary legless single bay that I eyeballed together over the weekend out of 49"x 1/8" welding rod steel. I'm watching all my local stations on it and I'm not sure with other stations being 80+ miles away even the correct DBGH will have the range to get much more, but I might as well try to do it right.

If I could find longer versions of the welding rod stuff I could perhaps spray the whole array with some sort of clear coat Rustoleum stuff to prevent rusting if that wouldn't muck up the reception/performance. The welding rod stock were like $2.50 a piece. A bitch to bend, but very sturdy. I wacked the thing bringing it in and out of the house and didn't disturb the shape of it at all.

Also you could try in rural areas, a farm supply place, like Central Tractor, or if still available in your area, a Southern States Co-op. They may have the thick solid aluminum cow fencing electric wire.

If the copper doesn't do the trick, I'll try the county co-op which is the place here for that. I didn't even think of them when I was in the other day for horse stuff.

Thanks for all the advice folks. I'm going to cut my supports parts and do my bending tomorrow so hopefully I'll have some pictures tomorrow night. I'm going to go for the dual bay with rod reflectors to start.

did try an electric supply place today that just looked at me like I grew a third head when I asked for #9 aluminum wire. I took my laptop with me and showed him the diagrams of the Hooverman and he offered me some copper stuff, I think it's 8-gauge copper. The invoice is a tad hard to make heads or tails off, but I think it was 36-cents a foot,

Very good price, he hasnt adjusted it for the recent rise in copper prices. Maybe you should have got the thicker 6 gauge stuff. Yes, they will look at you like from mars if you ask for 9 gauge wire. Common wire sizes are even numbers, like 6, 8, 10, 12, 14 etc.

Works better than the 4 bay bow tie it replaced.



Looks good. The indoor SBGHs look like mobiles, works of art.

Is your reflector spacing 100mm ? It looks closer than that from the picture.

Very good price, he hasnt adjusted it for the recent rise in copper prices. Maybe you should have got the thicker 6 gauge stuff. Yes, they will look at you like from mars if you ask for 9 gauge wire. Common wire sizes are even numbers, like 6, 8, 10, 12, 14 etc.

Well, if I have any problems with this array bending or such I'll try the thicker gauge. I have to admit I'm rubbish with types of wire. Don't know much about wire at all other than house wire that my dad left me a big spool of and of course speaker wire.

I'm actually just setting up to start my build. I wanted to get an early start but my neighbors horse got loose and wandered over to agitate my horses at 8am and I spent most of the morning walking the nag back over and getting entangled with helping the neighbor fix his fence. Well add barbed wire to the list of wire I know about. At least I didn't hammer my thumb this morning. Usually hammer my thumb at least once.

Anyway, I'm trying to work out how long to cut each wire in my array and I'm having a hell of a time trying to work out where I left the only ruler I have with millimeters and such. It would be great to have a version of the plan for those of us in the States where we still use backward inches and such. If there is one I've missed it so I've got to rewind this thread and see if there is one.

Okay, I'm really confused on my overall dimension. I found an old ruler which is marked in mm and inches, but I'm not sure that it's the right mm because 10mm on it works out to 3-15/16 inches.

I want to measure twice and cut once, so I'm worried about cutting my main wires to the correct length and I'm very confused by the whole metric thing here. When I tried using an online conversion thing it asked me if I meant to convert megametrics to inches and I about had a nervous breakdown.

I've paged through the thread several times and am more foncused than ever. Can I get these dimensions in inches because that's how my puny brain is hard-wired?

Sorry to be such a bother.

Is your reflector spacing 100mm ? It looks closer than that from the picture.

It is 95mm to the center of the tube, but so warped it is 100mm a little farther out....
I was going to make those reflector rods, but i broke some tubes bending them.
Is it better with those 12 rods?