More advice needed and very much appreciated. Many previous recommendations thus far, so narrowing it down to one of these one of these 2 antennas setups. SDS200 and dealing with Metal Roof in Mountainous area. The DPD OmniX Scanner Base or a Diamond D130NJ Super Discone. Using approx. 75ft of Davis RF 9914F "Bury-Flex" or LMR400 coax and a mast 6ft above highest point of the metal roof. Thanks in advance!!
OmniX or Diamond D130NJ
- Thread starter etuck
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OmniX will outperform a discone on 700-900mhz, I i tried a discone and did not perform well above my metal roof trying to listen to stations 25 miles away.
Hands down... Omni-x. I replaced all of my discones years ago and the Omni-x performance is outstanding
Bill
Bill
Omin-X definitely 
Thanks
Compared to what?
Border_Dave
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Here’s what my OmniX looks like on a 5 ft. mast on top of my two-story house. The OmniX is very small, durable, and lightweight. I’ve only had it up about four days at this point. I’m able to listen to the P.D. In Mount Vernon, which is about 55 miles away and on the other side of a large land mass. I’m beyond impressed with this antenna (and receiver).
Ubbe
Member
How does it compare with your old antenna at that height and same coax and what antenna was that?
We have no idea how high above ground you are and how high up the antenna for that site are for that system, so only a comparison to another antenna using the same height and coax would be useful.
/Ubbe
I have both the Omni-X and the D130N installed on the roof, with LMR400 coax for both connected to a switch (Alpha Delta) to my SDS200. The D130N receives some aircraft slightly better than the Omni (I can switch back and forth fairly quickly to test). Otherwise, it stays switched to the Omni-X all the time. If I had no external antenna and waa given the D130N, I'd be happy with it but as others said...Omni-X is an excellent antenna. Not cheap! I have three DPD antennas and they are expensive but they work very well.
What coax and footage did you use?
The two cables, is the 2nd one a ground and if so, how would you recommend it to be setup? I was thinking of mounting the same way, but
using 5-8 ft sch40 PVC pipe, being it would be such a short distance from the lower mast bracket. I was considering using just a coax ground
connection to a ground rod of some type. ???
The two cables, is the 2nd one a ground and if so, how would you recommend it to be setup? I was thinking of mounting the same way, but
using 5-8 ft sch40 PVC pipe, being it would be such a short distance from the lower mast bracket. I was considering using just a coax ground
connection to a ground rod of some type. ???
LMR-400, 50ft each. No coax buried but all are grounded (masts and coax) to a common ground rod via 8 gauge copper.
The LMR-400 is key for 800mHz+ freqs and makes the Omni-X sing, even with a bit of loss having the switch there. In fact, now that I think of I, I may dedicate the D130 to an SDR and connect the Omni-x directly to the SDS200 now.
The LMR-400 is key for 800mHz+ freqs and makes the Omni-X sing, even with a bit of loss having the switch there. In fact, now that I think of I, I may dedicate the D130 to an SDR and connect the Omni-x directly to the SDS200 now.
With the SDS200 stock antenna, I'm getting good 800 MHz but lacks in my local area, low band150-160MHz freqs. Even the OmniX being multi wide band, I was wondering if would need to be considering another type that's tuned even more to lower VHF freqs. But, then would
I weaken or loose the strong 800 UHV I'm now getting?
Thanks!
I weaken or loose the strong 800 UHV I'm now getting?
Thanks!
I have that diamond discone. Works great for me. I bought the mil Omni to try out. Didn’t see much difference on P25 living out it the country. Sold the mil Omni. With owning a Icom R8600, I needed the higher bandwidth too.
Border_Dave
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For my set-up, I used 50 feet of LMR400 Ultra Flex cable from the antenna to the window. I made sure to use a drip loop before it goes into the house in order to keep water from running down the cable and into my house/window. It is currently attached to a short flat cable (from here) to get it through (around) the window, and that is attached to another short run of LMR240 Ultra Flex coax cable to the receiver.
The green wire on the right is a 6 gauge insulated wire that is used for grounding purposes. I stripped one end and attached it between the vent pipe mount and the mast, making sure to sand off the painted coating of the mast in that location for good connectivity. As of right now, the other end of that ground wire is attached to an 8 foot ground rod that is pounded down into the earth right below that window.
When I get my lightning arrester (from here) in the mail tomorrow, I will insert it between the LMR400 coax and the flat cable that goes through (around) the window. I will then cut the green ground wire in that spot, install a ring terminal connector on both of the cut ends, and then attach them to the grounding point of the lightning arrester.
All outside coax connections will be sealed with coax seal and/or waterproof electrical tape.
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Per NEC, any additional ground rods must be bonded to the house main AC entry ground with no less than 6ga copper wire. An isolated ground rod on an antenna will usually damage more equipment in the house during a lightning strike.
Border_Dave
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Good to know. Can you provide a link to that NEC tidbit?
Edit: Nevermind. I found this. The problem I’m having is that my home’s ground electrode system (GES) is on the complete opposite side of the house. Hmmm. I wonder if I can connect the lightning arrester at the mast, before the 50 ft. coax run and then just run the ground wire to the GES on the other side of the house…
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Do a search on NEC article 810, that deals specifically with antenna grounding. A lot of people have the same problem with antennas on the opposite side of the house from the AC entry panel. The solution is usually costly and ugly.
When a satellite dish installer comes to your house the first thing they do is find a direct path to the satellite(s) with a short run of ground wire to the AC entry panel or other approved item. They are supposed to keep the 10ga ground wire run less than about 30 ft.
Same problem here, except approx. 80-100ft from location in garage to main house AC ground.
So if no metal mast is used, does the coax lightning arrester only, still have to go to existing house ground?
Sorry, I'm, totally new to this, as a hobby. I do very much appreciate everyone's info and time!!
So if no metal mast is used, does the coax lightning arrester only, still have to go to existing house ground?
Sorry, I'm, totally new to this, as a hobby. I do very much appreciate everyone's info and time!!
Although NEC has specific rules about grounding antenna masts and feedlines, if my antenna was far away from the AC panel but the coax passed near it on the way to the radio, I would install a lightning arrestor in the feedline and ground it close to the AC entry panel. In most cases grounding the feedline will also ground the mast to some extent.Same problem here, except approx. 80-100ft from location in garage to main house AC ground.
So if no metal mast is used, does the coax lightning arrester only, still have to go to existing house ground?
Sorry, I'm, totally new to this, as a hobby. I do very much appreciate everyone's info and time!!
Thats just my opinion for my station and you will have to decide what’s best and hopefully legal for your setup.
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