Zenith DTT901 - Page 72

I made a GH using fence wire for a reflector. It works great, even though it's only 3 feet off the ground and pointing at some thick vegetation.

Haha!
And then there's the CL 'garage saler' that keeps posting every imaginable combination/category of their stuff such that I have to weed through dozens of their ads. They keep sayiing at the bottom that they're moving. I wish they would move already!

Excellent. Looks like a big one.

Yeah I got to thinking that I would use rabbit cage wire rather than chicken wire. Probably not much price difference, smaller holes, and less dangerous except for the cut edges.

Yea, finally a new page here! Loaded much faster.

Yeah, independent furniture stores are often good for that, too. Many of them have been "Going Out of Business", for over a couple of decades.

TY for posting Peggy1, This was close to the size I was envisioning in my head. That looks like a very sturdy design, I'm taking there is no mathamatics involved in your reflector? Someone suggested using an old grill rack or metal refrigeration shelf. Fence wire? I used to use Stainless welding rod for small 220 & 440 band antennas, though whaeber you are using seems more sturdy.

Are you in a fringe area, or have very close UHF? I had this hooked up hanging from a celing fan on the second floor without the reflector, (with no amp either) & was able to pull the stronger UHF's in with no problem, & was actually able to be getting a pixelated picture on RF 8 via the 901. Now I understand the GH is very sensitive to direction & aim, plus I can put it up about another 5 feet from where I had it.

Thats the article I linked to get what information I have on this.

I'll try alone first before duplexing, & depending on RF 8 or 10, may be able to replace the Yagi.


More or less a RF cage then, we had these copper mesh rooms back when I did RF & enviromental testing years ago.

The reflector is just steel fencing. I used three-quarter-inch PVC pipe. I think half-inch pipe would be lighter and easier to cut. Signals are not particularly strong at my house. With this antenna sitting on the ground I have received WBRA (channel 3), WDBJ, WPXR, WSLS, WFXR, WVVA and WXII. I haven't tried it up high in the air.
http://www.tvfool.com/?option=com_wr...de6524ecf4df81

Sheesh, now there's another CL 'garage saler', even more posts than the other one. And there was another one a few weeks ago. Seems to becoming an epidemic like facebook.

And there were a whole lot more articles within my search results. Curious the reflector rods (per that author) vs. a reflector plane...

GL, they appear to be UHF in nature.

Ah, brings back fond screen room memories. We also had little portable ones for pagers.

Wow, you need a motor for your antenna or an omni.

I'm taking you may be up at a higher elevation yourself, & I see you are also receiving RF VHF channels too.

That steel fencing sold by the foot? Probably best to go with the 3/4" pipe you don't it that flimsy. You did a nice job with the T's & elbows.

I'm taking it the reflector size wasn't that critical in your case.

Actually, I'm not high up compared to the surrounding terrain. Although this antenna works for channel 3, I have a rooftop antenna for VHF that is much better. The fence wire might only be available in big rolls. I don't know. I used some that was left over from a fence project.

I should also mention that the T's I used for this project are called slip-T's or slip-slide T's. They are just for building things out of pipe. They are different than the ones for water pipe. They slide over the pipe, so there is less need for pipe cutting.

So this isn't standard PVC water pipe fittings I would find at the Home Depot?

& you arent securing with PCV cement?

You could use regular T's from the hardware store, of course, but the ones I used were completely different.

The glue was an epoxy for plastics, which worked well but had really overpowering fumes.

Before I built this one, I made a prototype antenna using a finer mesh for the reflector called hardware cloth. I think that antenna worked even better. But I used the fence wire for this outdoor antenna because I was concerned about wind and ice accumulation.

The "slip fittings" I've seen (also called "repair fittings") are used for repairs where you can't pull the pipes being joined apart enough lengthwise to get regular fittings in. They can be slid entirely onto one pipe, then slid back into position after the pipe ends are aligned. PVC cement should work fine for PVC slip fittings, although applying it could be trickier and messier than with regular fittings. I've used copper slip fittings (soldered into copper plumbing). I think plumbing supplies should have them, and maybe HD and Lowe's.

I wouldn't bother using glue for an attic antenna, then you could disassemble it if necessary. The schedule 40 stuff (usually white) I use for my pool plumbing fit together very tight as is, the glue is just for water pressure sealing. Save you money too and you won't goof up the pipe color with that colored primer (usually purple) not that that matters unless you reuse the pipes for something visible in the future. Schedule 80 pipe (usually gray) is for hot water usage and more expensive. There is a cheaper pipe, skinnier stuff (usually white), for low pressure apps (maybe for sprinkler systems).

I've never had all that much luck not using cement even for drain fittings (always seemed to leak without cement.. even on my AC drain).. then again don't want this falling apart either.

So an aluminum mesh screen would be an ideal reflector I would think though the fence matrerial peggy1 is using seems a lot more sound. This reflector doesn't have to be that much bigger than the elements, so size isn't that critical then if just using a fence grid, chicken wire or a mesh.

Maybe it's the type of pipe. I think I've played with sewer fittings at the Home Dashpot and they were loose. My schedule 40 fittings were actually kind of hard to disassemble when doing a test sizing. I've seen shelves and the like made with it with no glue. Check it out, sure beats not being able to take it apart if you mess up.

Yeah I don't know what's going on there as far as what it's 'reflecting' so to speak. I find it odd that the orginal design's incremental wavelength reflecting rods (or at least they were called reflecting rods in that article) are replaced by a uniform sheet. But hey these others say they work well so just follow their design guidelines.

General exterior dimensions for those elements are 28" x 22", I was thinking the external frame to be OD of 30" x 24" or 32" x 26"... & the reflector would aproximate that size. I was looking at mesh materials, a shame to buy so much for so little.

Somewhere In this mess I had the correct dimensions written down, is there a need to go that much bigger around the parimeter of the elements?

I hear ya, I've shunned away from such purchases having to buy a whole roll. Some places may sell off a huge roll by the foot, I started to say bigger places then thought of say an Ace HW that caters to smaller needs. Fencing supply places too.
I suppose you could revisit aluminum foil fab. Would it be possible to foil it after it's mounted?

I don't know but suspect there's a reason for the size given the spreading of waves. Probably some ratio of element to reflector plane required depending on what band you chose (design guidelines?). Hopefully one of the experts here can give you a better answer.

Mine is 38" x 28". There is no particular reason I made it that size, except that I had seen pictures of some of similar size.

The elements for my antenna were based on the first diagram on this page:

http://www.digitalhome.ca/ota/superantenna/design.htm

I used a wider gap between the elements because I read somewhere that it would be better. The distance between the elements on my antenna is 88 millimeters. The distance between the elements and the screen is 100 millimeters. I made my antenna 3 or 4 years ago. I understand that there are improved designs since then. But as I said, mine works very well.

I had referenced that site a few years back peggy1, though I think your design seems sturdier. What possible improvements had they made recently? I have yet to try mine outdoors or in my attic above the aluminum siding line, this is where it likely do better! I understand the Grey Hoverman has great gain, yet is extremely sensitive to direction too.

To keep on Topic, I'm back with the 901 once again (in tandem with the 13" RCA) as my New (used) LCD blew a board.... so I got 'just a taste' of HD TV over tha last 6 weeks.

I haven't followed it very closely, but people have come up with different designs. There are some designs that use reflector rods that, according to computer modeling, would have better VHF performance.

I would think that an outdoor antenna would be much better, if you have aluminum siding.

It's always good to experiment with antenna locations. When I was experimenting with mine outside on the ground right next to the house, it didn't work well for some channels. I guess there were signals bouncing off the house that were coming into the antenna out-of-phase and canceling out the signals from the other direction. But it works great attached to the porch railing.

This page mentions some different Gray-Hoverman designs:

http://www.digitalhome.ca/forum/showthread.php?t=81982

Is there a way to adjust the output brightness with this TV tuner? I don't see anything in the manual table of contents. I'm having problems adjusting the brightness output of my DVD player, a Philips DVP642, it's not responding to my attempts to make a "personal" setting for brightness, only Soft Standard and Bright are available, so I need to make a setting on the Zenith if possible. It's a PITA to always be adjusting my TV's brightness.

No setting for brightness, I note on my newer set where I use this as an aux tuner I now have to adjust the volume down to about 70 to balance things out.

Bismarck! lol. Hope all is well.
That 'kinda' seems odd to me as my Artec/Zenith-clone has Hue, Brightness, and Contrast in its Picture menu.
Of course it wouldn't help Muse's problem with the DVD player (at least the way I interpreted that post).

Yeah I get all kinds of audio variety with the boxes vs. output port and sometimes menu setting (Zinwells have an 'apparent' mono/stereo setting but they call it RF Mode/Line Mode; huge volume delta).

TY Floyage, hope all is well there too!

Are you suire the Artec is a clone? Same boards, but different firmware?

I don't think it has a picture menu only other than aspect Ratio.

Well the main board blew out of the Toshiba Flat Screen (at least what I think) on May 11th. The set hadn't been in service more than 2 years (purchased as old stock in June of '10) & the person I got this from treated it very well & was hardly home to watch it.

Are you well versed in LCD TV symptoms? There are only 3 boards in this set , & all signs point to the main. I'd replace it but I needed to be sure nothing else went out with it.

I liked the set while it was working.

I cant edit posts after the 'new & imptoved' changes, ssi I have to add.

Re Reading this it sounds like he's using a RF modulator for RF 4, though this is digital output, so I don't get what is being attempted here (running a DVD player through the Zenith box??).

Speaking of analog, out new RF 6 analog signed on here a few weeks back switching the calls from WXOX to WLFM, & will run audio also on 87.7 FM as a new local rocker.

Well no but... Same major chipset and if I recall correctly (about the Zenith) the OSD/menus look suspiciously similar. Form factor, boards, etc. are different and I don't know about the firmware. "Picture" on the Artec is a submenu within the "Option" menu.

That sucks! Yeah I wish I knew but not familiar with them, probably on AVS somewhere though. I'm not happy with Toshiba right now either. Acquired a friend's high-end SVHS VCR, it was working but I found a piece of plastic on the floor after opening it up to clean it (and it was filthy). I took the chassis out and when I went to put it back in it wouldn't work anymore, did this over again and then a ribbon cable that feeds out of the head (bad design, most plug down into the PC board like an IC) came loose from a wimpy cable guide and this time it decided to work only to rip the cable out when the head started spinning. When I disassembled the head I thought it was toast - 4 hair thin wires snapped that run up through a narrow channel inside (to avoid the rotating head). One wire snapped with only a few millimeters left but I painstakingly soldered a jumper to it and resoldered and routed the other 3. Now I got it back together but some tolerances between rotating parts and the PC board are so tight I can't get it to consistently run after screwing the chassis down (I think this is why it screwed up in the first place).
Oh yeah, the plastic piece doesn't appear to have come from this VCR (friend had it boxed in a customer return box for another model...). Well the pic didn't look as good as I expected so I thought something was wrong although I didn't have the high-end tape it probably desires (claims ET mode will record regular tape near SVHS quality but...).

Whew!