Laird vertical antennas for 800 mhz

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p1879

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My performance on a diamond discone and LMR 400 on 800 mhz is too poor for my taste. I have read back through many posts on RR, and some of the Laird antennas seem to get favorable mention. I am shopping for a 3 or 6 db gain antenna for around 860 mhz. I see Tram and others have antennas for this range, and I am not adverse to a used one. When I looked into this maybe a year ago, I saw some interesting possibilities on Ebay, still see some. What I am seeking is any opinions or advice on these type antennas. I could make a ground plane, or use a mobile cell antenna with radials, but I am more interested in trying something akin to the Laird ones. My preference is something no more than 100$.

Since we are talking 800 mhz, how do you think a vertical dipole inside a piece of PCV, using a tv balun as the feedpoint would work? Yes, i know that would tie me to RG6U or similar, which I think will be fine.

This topic has been hashed around here already, my apologies, but my hope is someone has a real "find" to share info on.

Thanks,
p1879
 

prcguy

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I would look for a used surplus commercial fiberglass omni to cover 800Mhz. Something in the 6 to 7ft range will get you about 6dBd gain and an 11ft will be about 9dBd. The Laird and Tram mobile antennas with a ground plane kit might be 3dBd gain at best, otherwise don't believe their gain advertisements.

A home made dipole will give you 0dBd gain and you don't want to use a TV balun to connect a 75 ohm antenna to 75 ohm coax. The balun is a 75 ohm to 300 ohm transformer.
prcguy


My performance on a diamond discone and LMR 400 on 800 mhz is too poor for my taste. I have read back through many posts on RR, and some of the Laird antennas seem to get favorable mention. I am shopping for a 3 or 6 db gain antenna for around 860 mhz. I see Tram and others have antennas for this range, and I am not adverse to a used one. When I looked into this maybe a year ago, I saw some interesting possibilities on Ebay, still see some. What I am seeking is any opinions or advice on these type antennas. I could make a ground plane, or use a mobile cell antenna with radials, but I am more interested in trying something akin to the Laird ones. My preference is something no more than 100$.

Since we are talking 800 mhz, how do you think a vertical dipole inside a piece of PCV, using a tv balun as the feedpoint would work? Yes, i know that would tie me to RG6U or similar, which I think will be fine.

This topic has been hashed around here already, my apologies, but my hope is someone has a real "find" to share info on.

Thanks,
p1879
 

dlwtrunked

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I would look for a used surplus commercial fiberglass omni to cover 800Mhz. Something in the 6 to 7ft range will get you about 6dBd gain and an 11ft will be about 9dBd. The Laird and Tram mobile antennas with a ground plane kit might be 3dBd gain at best, otherwise don't believe their gain advertisements.

A home made dipole will give you 0dBd gain and you don't want to use a TV balun to connect a 75 ohm antenna to 75 ohm coax. The balun is a 75 ohm to 300 ohm transformer.
prcguy

Indeed. However, if he were instead to use a folded dipole which would give him greater bandwidth (perhaps if he is wanting both 700 and 800 MHz), the impedance of those is somewhere around 200 to 300 ohms and such a balun would be good if designed for that frequency range. Also, before it comes up, no one should ever use 50-to-75 ohm transformers to convert impedance for receivers as, besides the cost, their loss is greater than that small amount for the impedance mismatch.
 

prcguy

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Speaking of folded dipoles, I had an 800MHz dual folded dipole array on RR swap page for real cheap and nobody wanted it. I finally broke it apart and put in the trash can.
prcguy

Indeed. However, if he were instead to use a folded dipole which would give him greater bandwidth (perhaps if he is wanting both 700 and 800 MHz), the impedance of those is somewhere around 200 to 300 ohms and such a balun would be good if designed for that frequency range. Also, before it comes up, no one should ever use 50-to-75 ohm transformers to convert impedance for receivers as, besides the cost, their loss is greater than that small amount for the impedance mismatch.
 

p1879

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The kind of antenna I have in mind is indeed the large, commercial type antenna, which I plan to use for 800 mhz trunking. Laird, and I have read that Tram also makes some like that......I did notice many on ebay were only unity gain, and I feel sure a 3 db antenna at 25 feet will give me some results--I am on a pretty good site anyway. Right, I was asking about the larger antennas housed in what looks like fiberglass, and usually have N connectors. I was hoping someone knew some obscure source with a good deal. Specifically an antenna for around 860 mhz.
I do appreciate your effort.

I will get back to hunting on ebay after the tax anxiety gets over...
p
 

prcguy

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I occasionally see surplus Celwave and other large fiberglass 800 antennas on Ebay for good prices, just keep looking. Another place to find them cheap is ham swap meets.
prcguy

The kind of antenna I have in mind is indeed the large, commercial type antenna, which I plan to use for 800 mhz trunking. Laird, and I have read that Tram also makes some like that......I did notice many on ebay were only unity gain, and I feel sure a 3 db antenna at 25 feet will give me some results--I am on a pretty good site anyway. Right, I was asking about the larger antennas housed in what looks like fiberglass, and usually have N connectors. I was hoping someone knew some obscure source with a good deal. Specifically an antenna for around 860 mhz.
I do appreciate your effort.

I will get back to hunting on ebay after the tax anxiety gets over...
p
 

trp2525

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The kind of antenna I have in mind is indeed the large, commercial type antenna, which I plan to use for 800 mhz trunking. Laird, and I have read that Tram also makes some like that......I did notice many on ebay were only unity gain, and I feel sure a 3 db antenna at 25 feet will give me some results--I am on a pretty good site anyway. Right, I was asking about the larger antennas housed in what looks like fiberglass, and usually have N connectors. I was hoping someone knew some obscure source with a good deal. Specifically an antenna for around 860 mhz.
I do appreciate your effort.

I will get back to hunting on ebay after the tax anxiety gets over...
p

You should take a look at the Laird FG8243 and the Laird FG8246 fiberglass omnidirectional base station antennas as they may be what you are looking for:

Laird FG8243: 824-896 MHz, 3 dBd gain, 25" length, N female connector

Laird FG8246: 824-896 MHz, 6 dBd gain, 65" length, N female connector

Solid Signal is a very reputable dealer that I have personally ordered from in the past and they have some very good pricing on these antennas. If you shop around you MAY be able to do a little better on pricing but you will also see some MUCH higher pricing. YMMV

Laird FG8243 (List Price $136.99) for $83.53: https://www.solidsignal.com/pview.asp?p=fg8243

Laird FG8246 (List Price $187.99) for $126.30: https://www.solidsignal.com/pview.asp?p=fg8246

Link to the Laird Product Manual at Solid Signal (see page 4 of 8-page pdf file): https://manuals.solidsignal.com/YagiAntennaDatasheet.pdf
 

p1879

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Thanks for all the help. I did order the Laird FG8246 6db gain antenna. My hope was I could find something similar from some surplus outfit like the beloved Meshna Surplus or Fair Radio Sales. Fair is still in business, it was quite nostalgic to read over their pages and see the cool stuff they have. Now I have to suffer the bite from the cable cost, but it will be a good feeling to have a quality installation. I have a challenging goal reception-wise and hope this will make it happen.

p1879
 

trp2525

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Thanks for all the help. I did order the Laird FG8246 6db gain antenna...

If you haven't done so already, you should also order the Laird FM2 Fiberglass Antenna Mounting Kit (List Price $33.77) to mount your new fiberglass antenna to a mast for $19.64: https://www.solidsignal.com/pview.asp?p=69293

Also for comparison purposes Scanner Master charges $189.95 for the Laird FG8246 antenna compared to the $126.30 selling price at Solid Signal (see above). Scanner Master's price is 50% higher than the price at Solid Signal: Laird FG8246 Omni Base Antenna | Scanner Master
 

prcguy

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Mendelsons in Dayton has real 10dBd gain Celwave Super Stationmasters in the 885 to 920MHz range for $143.65. These probably cost nearly $2k new these days.
prcguy





Thanks for all the help. I did order the Laird FG8246 6db gain antenna. My hope was I could find something similar from some surplus outfit like the beloved Meshna Surplus or Fair Radio Sales. Fair is still in business, it was quite nostalgic to read over their pages and see the cool stuff they have. Now I have to suffer the bite from the cable cost, but it will be a good feeling to have a quality installation. I have a challenging goal reception-wise and hope this will make it happen.

p1879
 

trp2525

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...Now I have to suffer the bite from the cable cost...

If you haven't sourced a cable supplier yet, you might want to add Field Components Inc. in East Hampton, NY to your list of potential cable suppliers and get a price quote from them. They carry genuine Times Microwave LMR series cable (LMR400, LMR400 Ultra Flex, etc.) and will install whatever connectors (N male, BNC male, etc.) you need to terminate the exact length of cable you need. They also offer FREE ground shipping in the domestic USA for internet orders over $100.

Here's the link to their website: https://fieldcomponents.com/
 

p1879

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Mar 15, 2004
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I liked the Solid Signal price, the shipping was only 12$ and I did get the mounting brackets.Other places wanted more for the antenna, much more for shipping, and some indicated 4-6 weeks delivery time.

I am not so sure I want to even keep the Diamond Discone up, it seems poor to mediocre everywhere. I think the popularity it enjoys must stem from the wideband transmit potential . A Channel Master 5094 or Scantenna is much better for my needs.

I will be cable shopping, thanks for the tip.

10dBd gain Celwave ...would love one! Bet it needs some stout support, though.

I just hope this does not lead to preamplifier shopping...have one in my sights but would rather wait and see how things go as-is.

thanks folks,
p
 

scanmanmi

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I had the same problem (hard to believe). Late last fall I was at a hamfest and picked up a big yagi so I thought I would experiment with it. It solved all of my problems since I monitor nothing north of me. I'm picking up towers several counties away. I put a T in and have my scanner antenna just above it. I know this is not optimal but winter came. This spring I will look at improving the spaceing, phasing, and coupling. Maybe something like this https://www.newegg.com/Product/Prod...6SX1078&cm_re=yagi-_-9SIA6RP6SX1078-_-Product This one ships from Israel so you may need something similar if your observing BDS https://bdsmovement.net/
 
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