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Old 11-Jun-2013, 7:38 AM   #22
Pete Higgins
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Join Date: Apr 2013
Location: California, 58 miles @112 degrees from Mt. Wilson
Posts: 83
HDB8X Harness

tripelo,

I knew some of what you mentioned in your last post but definitely not all.

When I assembled the antenna, I noticed that the coax was unusually thin and very flexible with rubber boots and molded connectors installed @ each end.

Yesterday, I decided to document the coax harness and test it and the supplied combiner (by substitution). Fortunately, the coax was marked as 3C-2V, which made looking up its specs. relative easy. It is just another form of 75 ohm coax.



I was surprised to find a ¼” difference in length when measured from screw-on edge to screw-on edge. First, I substituted two length matched 36” pieces of RG-6 between each of the HDB-8X’s BALUN's to the combiner. Worst case loss for 34” of 3C-2V@ 700 MHz = ~.268 dB and should be insignificant compared to RG-6 @ .217 dB. Needless to say, this test didn’t yield any noticeable difference. Next, I left the RG-6 connected to the BALUN’s and substituted an ordinary 1 GHz 2-way splitter for the combiner. Again, no noticeable difference in SNR.

Here is a picture showing the installation and comparing antenna sizes.



I want to try some ideas suggested by your post but I’ve got to finish refurbishing a CONDO.

I bought a 5 year old 3 Br./3bath CONDO for my wife’s son just after I retired and he trashed the whole place. Just a few more hours work & we’ll have it ready to rent –to someone else. Maybe tomorrow or Wednesday I can get back to playing.
Attached Images
File Type: jpg 5. Closeup HDB8X-CM-4228.JPG (108.2 KB, 8538 views)
File Type: jpg Harness Specs 2.jpg (84.3 KB, 7097 views)

Last edited by Pete Higgins; 17-Jun-2013 at 7:56 PM. Reason: Add pictures back in.
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