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Discussion Starter #1 (Edited)
I have been searching the Forum to try and see if anyone has built the GH8 and what sort of real world reception results they have had with it.

Searching the forum has not yeilded much - it seems difficult to search using a short word like GH8.

Plus, it does not seem to me that many have built the GH8. Lots of GH6 and GH10 - not so many GH8 - or am I wrong ??

Member Firimari seems to have built one.

The reason for my interest in the GH8 is as follows:

The specs j3d (John E. Davis) has on his "jedsoft" web page for the GH8 seem good and interesting to me.

http://www.jedsoft.org/fun/antennas/dtv/gh.html

Gain of the GH8 seems relatively flat across the UHF band, compared to the GH10 - but the GH8 also has consistently higher gain than the GH6 across the whole band.
(SWR of the GH8 seems consistently flatter and lower also - generally - across the band)

So ... compared to the GH6, for just a couple extra co-linear reflectors, the GH8 seems to give you some moderate advantage for not a big extra cost.
(So it seems like a good one for me to try and build and test)

So ... Anyone out there build the GH8? Or the the Double GH8?

What are your practical, real world results with the GH8? Reception?

Have any problems with the GH8 ?

GH8 advantages or disadvantages?

Most interested. Thanks in advance for your help and advice.
 

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Unfortunately, the build quality of my Grey Hoverman left a bit to be desired. I haven't built a new one to compare against, but it was better than the ChannelMaster 4221 I had previously.

Note that I built the gapless Grey Hoverman, not the 'standard' one at jedsoft's GH page. I'm currently procrastinating a new build based on XGH8. The snow and ice on my roof is not motivating me to finish.
 

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I`ve been using GH8 elements only in my combo builds . It has alot more umph to them over the GH6 elements . What I like about the 8`s the most is that they peak in gain on the upper UHF which is where my desired , low powered RF50 is. I also played with the GH10 elements and they were good on low UHF but the gain dies off after RF 47. I did a gapless version of that and found it to be hard to top . I tried the GH8 with the rod reflectors , made quite an improvement but I found in my area I can go reflectorless. I prefer a cleaner , simpler build.
However I moved the antenna to the back of the house onto a tower and lost alot of signal due to the tree factor. The XG91 is useless in that spot but the GH8 pulls it all in . I did lose some stabiliy on RF50 so I tried a 1x2" screen behind it , only 24" wide but thats all I had and it cured the RF50 problem .
The GH8 impresses me but a gapless GH10 would give you more signal yet.
 

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mrvanwinkles,
If you haven't already done so, try a Google advanced search on gh8, which is equivalent to a search on this:

gh8 site:digitalhome.ca/forum

When I did this a few minutes ago, I got 323 results.
 

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Discussion Starter #6
Thanks for all the advice on how better to search.

Yes, that has allowed me to find more GH8 information on the Forum.

There is an interesting discussion in one thread about the wide "feed gap" issue on the GH8 causing matching issues, and matching losses to the balun.

... and then also the losses introduced by of some questionable baluns / poor performing matching transformers themselves.

Talk of tapered rod extensions at the feedpoint, to bring the feed point closer in ... for better matching to a 300 ohm cable, to the balun, then to the coax.

Wonder if anyone has experimented furthur on the "Feed Point" issue, or with tapered extensions at the feedpoint.

(Coax loop baluns are mentioned as better ... but I read somewhere else that coax loop baluns are more "narrow band" ... and transformer style baluns are more "broadband")

Anyway ... there seems to be some signifigant losses in the matching of the antenna to the transmission line.

Wonder if there has been any work to solve this issue.

There may be something to be gained there.

Please feel free ... keep posting information and advice for the GH8 on this thread. Much appreciated.
 
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