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Old 14-Sep-2018, 8:13 PM   #22
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,747
Quote:
Originally Posted by niv
I’m sure most of the east coast is going to be affected by Florence. Hopefully you will be minimally impacted. . .

I’m remembering about my wire job after looking up the the antenna on Amazon and seeing a comment about a design flaw in the antenna. About 3 years ago the antenna was blown down because a roofer undid a guy wire and of course shortly there after a storm blew in from that direction taking it down. I had gone through a bad 3 year period, this was the 3rd time in that period it had gone down. I put it back up but about 3 or 4 feet lower. Ch 12.1 went away, I wasn’t relying on the antenna so I didn’t do much about it. With the Rio Olympics approaching I got serious about getting 12.1 back (NBC) I did things like replace the spliced coax with a home run lead. A storm had rearranged the elements so I took the opportunity to take the antenna off the mast and check it out, tightening things etc.

The antenna has a squirrley bare metal line on either side that goes through the black plastic downlead box. It is very difficult to get it to fit right even when it was brand new. It also connects front and back sections of the antenna. Somehow I managed to mangal the junction between sections which wasn’t hard to do the way it is constructed. I put an addition wire between the joint just to make sure there is a good connection between the 2 sections. It was just before the Olympics that I remembered that it wasn’t as high as it had been prior to it being blown down. Put it back up to full height and was able to watch Rio via OTA rather than the highly compressed Dish locals.

If this somehow comprises the effectiveness of the antenna I will replace the antenna. For me to succeed in this endeavor I must be able to reliably receive 3.1, 5.1, 8.1, 10.1, 12.1, 15.1, 45.1 & 61.1 on both the SDT and the Hopper OTA tuner.

Would eliminating the 3 foot cable from the antenna to the PA have any impact? I could tether the FM trap and the PA directly to the antenna, putting a spacer on the other side of the PA and secure it to the under carriage of the antenna. Downside would be the connectors of the PA would be facing upwards. I know you want to have drip loops in cables. The Juice PA looks to be sealed pretty well and we have thus far thad 5.5 inches of rain (2.6 in Aug) this year and don’t anticipate much more (maybe a little in Dec) for the rest of the year. Rain isn’t a problem factor in Phoenix.

FM trap works well. I first put it in at the DA level, antenna directly to FM receiver feed. When from great FM reception to no FM reception. Then put the PA back on line with the FM trap in front of it. Going through the DA, trusty LG on 12.1 results were the same as without the trap. (s=signal strength Q=quality) S-54 Q 19-21. THEN it started swinging wildly. Q when from 2 - 96. S more stable going between 54 - 56. Time was just before noon. Didn’t get those wild swings prior to the FM trap.

On the SDT No 3.1 S-91 Q-0 or 5.1 S-81 Q-0. I don’t want to scan for 12.1 because I might lose access to checking 3.1 & 5.1.

Picture links will show what I mean by tether, Trap is tethered to the antenna. Also closeup of my wire job.

https://tinyurl.com/ydh7r4rc
https://tinyurl.com/ydam6g9v
Quote:
Would eliminating the 3 foot cable from the antenna to the PA have any impact? I could tether the FM trap and the PA directly to the antenna, putting a spacer on the other side of the PA and secure it to the under carriage of the antenna.


Either way will work. There is very little loss in a short length of coax; a small fraction of a dB. Mechanical and weatherproofing considerations should determine which way to do it.

Quote:
I put an addition wire between the joint just to make sure there is a good connection between the 2 sections.


If you are saying that you connected the UHF and VHF sections of the antenna together with that wire, it's a bad idea that will ruin the performance of the antenna. The VHF section of the antenna will pick up UHF signals that will interfere with the UHF signals from the UHF section. You are defeating the purpose of the UVSJ (UHF/VHF Separator-Joiner) in the CB-8269.
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Last edited by rabbit73; 14-Sep-2018 at 8:45 PM.
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