: Finally built my SBGH!


Elvis Gump
2008-05-01, 01:03 AM
After many fits and false starts, math errors and skill shortcomings, I finally hobbled my version of the a single bay Gray Hooverman.
http://farm3.static.flickr.com/2248/2455385429_1311d2f11e.jpg

Here's a closeup of the feed-point
http://farm4.static.flickr.com/3263/2456225804_ff5eec5c8a.jpg

I tried using a cheapo Craftsman drill press adapter thing to drill holes through the 1" salvaged square aluminum tube to insert my reflector mounts through, but the thing just wasn't precise enough when I got into larger bits.
http://farm3.static.flickr.com/2273/2455379833_79864014ff.jpg

I ruined one tube, but since it was something I salvaged it wasn't so bad.
That did though sort of put the kibosh on building a DBGH.

I decided to recycle some parts that had held on larger hollow tubing to the old VHF antenna I was scavenging. But this also limited me to the SBGH because I only had enough cleat things to make a SBGH like this. (back view)
http://farm4.static.flickr.com/3118/2456231416_094f566bf8.jpg

Since it's clear skies until Friday night I'm going to wait til tomorrow to ground it and all, but I'm enjoying the reception tonight. I can pick up few more distant channels, though there's nothing really within 100 miles that I can't get locally so it's sort of moot for range.

I do now though get all five bright green bars on my PBS station which is 40 miles away, so I've really been enjoying "Carrier" tonight on PBS.

Thanks to Autofils for this great design!

300ohm
2008-05-02, 02:03 AM
Nice looking SBGH. Those salvaged clips to hold down the reflector rods do a nice job.

What I would do though, is to replace the steel bolts (unless they are stainless steel, I cant tell from the picture) at the feed point with same size brass bolts. After a few rains, they will be much easier to undo.

stampeder
2008-05-02, 03:01 AM
After a few rains, they will be much easier to undo.Either that or go with hex head machine screws or Robertson-head screws.

Elvis Gump
2008-05-02, 10:40 AM
Either that or go with hex head machine screws or Robertson-head screws.

NOW you tell me when I already got it 30ft in the air! :eek:

I may wait until the first windstorm rattles it around or damages it. I'm having quite a wind even this morning with a storm approaching. I'm thinking about taking one of the 5 ft pole sections out because there's really no place for me to hard mount some guy wires. I'm reticent to drill mount points in the roof decking and running into the yard seems pretty extreme. I only wish my dad hadn't had the chimney demolished years ago because it was a good mount point. The only things I have left are the vent pipes for the plumbing and I don't think they'd be good mount points and there's not enough of them to make a true triangulation anyway.

As it is about 30ft up it dances a bit with the bracket to the facia board only about 10ft at the highest brace point.

My only alternative is to move it to the front side and lower it a bit since the height right now is just to get it shooting over the ridgeline of the roof over the house toward the tv transmitters. My prototype was lower on a light stand outside this past month in front of the house but it did nearly as well as this so that maybe my next option, but it means rerunning all the cabling.

stampeder
2008-05-02, 11:41 AM
The only things I have left are the vent pipes for the plumbing and I don't think they'd be good mount pointsNope, definitely not a good idea to try to mount to those - they're too weak and the vibration will destroy their caulking if not the pipes themselves.