Quote:
Originally Posted by IDRick
..... First, I do not believe the AD specs on the DB-8. It does not have a 100 degree beamwidth. ....
Rick |
Rick,
A little OT for the thread at hand....
This subject just came up on one of the other forums.
I've looked all over AD's website and nowhere do
they claim such a beam width for the DB8. So far, I can't find
ANY claim of a beam width on their site for the DB8, either now or in the last several years (searched via archive.org). Other than online resellers erroneously claiming such a beam width, I can't find such a reference.
Based on polar plots they sent me a while back, it appears to have a BW of around 20-35 deg depending on frequency.
Just trying to figure out where that 100 degree number came from.
Quote:
|
From experience and other's statements, reception of HiVHF has always been a little sketchy on the "Bow" Type antenna, though the Mfg imply they do it.
|
Ironically, I was playing with a DB8 at my sister's farm out in the middle of nowhere, Missouri today. I had the DB8 pointed at St Louis and was pleasantly surprised to receive KRCG-13 (VHF-12) from Jefferson City with the antenna either pointed at St Louis (about 60 miles) or at Jeff City on my Artec T18AR USB tuner. My Sencore's reading showed that the "real" gain on VHF-12 was about -10 dBd but, even at 41.7 miles (TVF NM of 17.5), that little T18AR still picked it up without errors. KOMU-8 (56 miles, NM -2.3) was completely absent on the DB8 but was easily caught by pointing a C5 at Columbia instead of the DB8.
TVFool plot for that location:
http://www.tvfool.com/?option=com_wr...8adf782ae24e24
Sencore's BAR scan of the DB8 pointing at St Louis:
[IMG]
[/IMG]
Sorry about the legibility - the well-used meter's screen is tough to read in bright sunlight and harder to photograph clearly.
Ref level (top line) -18.7 dBmV
From left to right, the bars represent the signal strength of the channels in the current channel plan. Levels near or below the bold horizontal bar (-51.0 dBmV) are unused or are representing noise.
RF Channels
12, 14, 24, 26, 31, 35, 39, 43, 47, 55
All of these channels (except 55 of course), tuned right in with the little Artec on my laptop.
If you do desire some of the weaker stations, you will need to rely on proper antenna selection for any chance of reliable reception. (Been there/done that more than once). 
Linear Mode
