[mythtv-users] Pre-amp for Hauppauge 1600

[Dave Day]

On 05/18/2010 07:18 AM, Brian Long wrote:
> On Sun, May 16, 2010 at 1:06 AM, Dave Day <david.scott.day at gmail.com 
> <mailto:david.scott.day at gmail.com>> wrote:
>
>     I ended up building a single bay Gray-Hoverman (one hour at Home
>     Depot and 3 hours at the work bench). The particular version I
>     built is considered a UHF only antenna, so my plan was to first
>     fix my main problem which was the UHF stations, and then I thought
>     I would build a yagi for the two vhf ones.
>     Of course when I finished it I was anxious to get a hint of
>     whether it would help.  So I went to the attic and just set the
>     SBGH down on the attic floor under the rotor/antenna and moved the
>     RG-6 coax to the balun on the Gray-Hoverman.  I pointed the SBGH
>     in the general direction of my stations and went to check the
>     reception.  It was great!  Apparently all the stations are pretty
>     comfortably above the threshold where lock occurs because the
>     pictures on all 7 stations are basically perfect.  And,
>     ironically, the two VHF stations are as good or better than they
>     were before, even though the SBGH model I built is supposed to
>     only be a UHF antenna.
>
>
> Specifically which SBGH plans did you use?  I found the DigitalHome 
> forum and wondered which plan you used.
>
> http://www.digitalhome.ca/forum/showthread.php?t=81982
>
> Thanks.
>
> /Brian/
>
>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users at mythtv.org
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>    
Brian -

http://www.digitalhome.ca/forum/showthread.php?t=95898

I built 300ohm's original screen mesh reflector SBGH, the plans for 
which are detailed in his post in the above thread.  Scroll down till 
you see the diagram which is mostly yellow.  It is the simplest to build 
and will give you a feel for whether you really need the incremental 
improvements in performance provided by the other more sophisticated models.

I understand a little better now the difference between my two 
antennas.  My original antenna was a Radio Shack which had 6db gain for 
both UHF and VHF.  This Gray-Hoverman has 14db gain UHF and apparently 
more than 6db gain  for my VHF-HI channels (since the SBGH gets them 
better than the Radio Shack with 6db gain).  Eight db of improvement is 
BIG.  I didn't split the reflector screen so there is another 1 db of 
free gain available  should I decide to take it back down and snip out 
the center of the screen.

Most of my problems were in the UHF between channels 20 and 50 and that 
is where the Gray-Hovermans have their highest gains.  Now those 
channels are my strongest.

I originally intended it to be a DBGH so I did use tees and crosses on 
the bottom so it can easily be converted to a DBGH, but now I don't 
think that will happen since I seem to have plenty of signal from the 
SBGH.  I might install a low gain preamp so I can add some splitters to 
service another TV and the analog portion of the HVR-1600, since there 
is a TBN station locally that is still analog.

So, have fun,
Dave


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mythtv.org/pipermail/mythtv-users/attachments/20100518/c2501f21/attachment.htm>