I scan a few somewhat nearby 150 & 450MHz transmitters (~5-10 miles max), but I really want to pick up some 800MHz sites that are about 40 miles away (they are mostly LOS over water). I don't really want to get into a multi-antenna setup. Would I be better off using an 800MHz tuned antenna such as the Browning BR-6290 or Laird FG860 or a 25-1300MHz discone such as the Tram 1410? I'm thinking the former as I believe I can deal with reduced VHF performance without sacrificing anything and I have read that discones don't really do that well on frequencies above 500MHz. A Yagi is a no-go as I have several different directions I want to monitor from and I do not plan on transmitting, just scanning.
800MHz on discone
- Thread starter jsncrso
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My 2 cents. If you are dealing with local strong signals in the VHF/UHF region, an 800mhz tuned antenna may work for you; I've done this successfully for years a few decades ago. However, your main problem will likely be trying to receive 800mhz sites 40 miles away. I can't comment too much on your specific situation, but in most places that is a tough proposition. I little poking around the RR DB reveals alot of the sites for VIPER around outer banks are little more than 300 feet tower/ant height. Unless you have significant elevation advantage or tower height, reliable reception may not be possible.
A common test suggested here goes something like this. If you have an HT that can receive 800 in any way, put a good 800mhz antenna on it. Now get up to the high point where your anticipate putting your antenna, assuming you can do so SAFELY. If you can receive what you want well, your golden.
A common test suggested here goes something like this. If you have an HT that can receive 800 in any way, put a good 800mhz antenna on it. Now get up to the high point where your anticipate putting your antenna, assuming you can do so SAFELY. If you can receive what you want well, your golden.
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Themore common discones do not do that well above 500 MHz as the spacing between the top of the cone and disk affects upper end performance. There are though discones (smaller and expensive) that are designed for "up there " like the Diamond DA6000. I do not know how well it will work on you lower frequencies. I might try the Sirio SD3000N which lists 300 MHz as is low designed limit. Personally, I would go for two antennas despite you which. I would stay away from the Tram.
I use a discone to monitor a neighboring county's 800 system. Their sites are on mountain tops more than forty miles from me, I also have various size hills between us.
I can pickup one of the sites on an SDS100 with the stock rubber duck if I move it around, on the discone there is no problem.
If any problem I have is the simulcast distortion on the non SDS scanners.
My advice, try the discone first, if it doesn't work well then try an 800 Mhz. antenna.
And of coarse it all depends on how their radio system is set up, how high up the repeater antenna is, the power output.
I can pickup one of the sites on an SDS100 with the stock rubber duck if I move it around, on the discone there is no problem.
If any problem I have is the simulcast distortion on the non SDS scanners.
My advice, try the discone first, if it doesn't work well then try an 800 Mhz. antenna.
And of coarse it all depends on how their radio system is set up, how high up the repeater antenna is, the power output.
I use a discone to monitor 800 mhz systems that are ~40 miles away, and UHF and 800 systems that are closer. I have elevation in my favor providing a fairly clear LoS to the south and East which is the direction of those distant systems.
A discone would probably be your worst choice for 800 MHz.
prcguy
Member
I tested a typical Radio Shack sized Discone on 800 taking precise signal strength measurements then swapped it with a tiny Maxrad brand Discone rated for about 300MHz to 2.4GHz. The signals in the 800 band came up right around 10dB on the tiny Discone and that is very significant.
Whenever I do a Discone I now supplement it with a 700/800/900 omni from L-Com and a diplexer to combine them together on one coax. The L-Com HGV-906U series covers 800-960MHz with about 6dBi of gain and also works great in the 700 range. These are about 3ft tall and have at least 3dB more gain than a tiny Discone designed for the 800 range so that would put the L-Com about 13dB better than a Radio Shack or Comet D130J type Discone on 800. I've picked up lots of the L-Com antennas new off eBay in the $30-$40 range and use various diplexers also off eBay cheap.
Whenever I do a Discone I now supplement it with a 700/800/900 omni from L-Com and a diplexer to combine them together on one coax. The L-Com HGV-906U series covers 800-960MHz with about 6dBi of gain and also works great in the 700 range. These are about 3ft tall and have at least 3dB more gain than a tiny Discone designed for the 800 range so that would put the L-Com about 13dB better than a Radio Shack or Comet D130J type Discone on 800. I've picked up lots of the L-Com antennas new off eBay in the $30-$40 range and use various diplexers also off eBay cheap.
I don't think the OP has a L-Com HGV-906U antenna or anything close to it. Most likely a Radio Shack or Comet D130J type Discone or similar.
prcguy
Member
Thanks for all of the replies! That Sirio discone looks interesting, but reading through the thread, it looks like I'll be better off using two separate antennas even though it wasn't my first choice. I have an extra scanner and I'll probably have one on VHF and the other on 800
I have no problem picking up 800 MHz with my discone at 40 miles. Height is key.
prcguy
Member
The Diamond D130J is known to be good quality and there are a few others, although I would leave the top whip off. I bought a number of L-Com HGV-906U antennas cheap but am low on stock at the moment, otherwise I would offer one to the OP at my cost.
I have a discone just above a 2 story roof and it works very well with everything from 100 through 900 Mhz.
I pick up an 800 Mhz site nearly 60 miles, albeit to weak for monitoring.
Hard to beat with a scanner but I find local signals can use the attenuator on.
I pick up an 800 Mhz site nearly 60 miles, albeit to weak for monitoring.
Hard to beat with a scanner but I find local signals can use the attenuator on.
As far as distance possible, it really depends on the design and construction of the systems that you are trying to monitor, which can vary widely. It didn't take me long to find sites in my area with a 12:1 difference in licensed ERP (effective radiated power) – almost 11 dB. That's can be the difference between hearing it at a distance of 15 miles versus 50 miles away. Or between hearing it with a rubber duck or needing a big, expensive, high-gain antenna,
Uh ? Maxrad makes discone antenna's ??
prcguy
Member
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