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Indoor Omni Antenna 550-600mHz Suggestions
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Klay Anderson
Jan 5, 2021, 5:47:10 PM1/5/21
to
I'm in need of an indoor omni antenna (actually two) in the 550-600mHz range. I've found a few with 5-9dBi gain from Italian manufacturers. And while we are well versed in importing, we find their pricing....well, shockingly high. Any US ideas?
Peter W.
Jan 5, 2021, 6:51:13 PM1/5/21
to
https://en-us.sennheiser.com/a-1031-u
Like this, or am I missing something? About US$150 or so.
Peter Wieck
Melrose Park, PA
Like this, or am I missing something? About US$150 or so.
Peter Wieck
Melrose Park, PA
Clifford Heath
Jan 5, 2021, 10:19:47 PM1/5/21
to
On 6/1/21 4:47 am, Klay Anderson wrote:
> I'm in need of an indoor omni antenna (actually two) in the 550-600mHz range. I've found a few with 5-9dBi gain from Italian manufacturers. And while we are well versed in importing, we find their pricing....well, shockingly high. Any US ideas?
>
PSA: omni antennae do not have gain, because gain is always quoted wrt
> I'm in need of an indoor omni antenna (actually two) in the 550-600mHz range. I've found a few with 5-9dBi gain from Italian manufacturers. And while we are well versed in importing, we find their pricing....well, shockingly high. Any US ideas?
>
an omni (isotropic) antenna having gain of 0dB.
Also, I doubt you have a house big enough to contain an antenna for
550-600 milli-Hertz.
Phil Allison
Jan 6, 2021, 12:15:54 AM1/6/21
to
Clifford Heath wrote:
=======================
Any vertical whip type is an omni and can have considerable gain.
=======================
>
> PSA: omni antennae do not have gain, because gain is always quoted wrt
> an omni (isotropic) antenna having gain of 0dB.
>
** Wrong. Omni and isotropic are not the same.
> PSA: omni antennae do not have gain, because gain is always quoted wrt
> an omni (isotropic) antenna having gain of 0dB.
>
Any vertical whip type is an omni and can have considerable gain.
Phil Allison
Jan 6, 2021, 12:19:41 AM1/6/21
to
mailser...@gmail.com wrote:
==========================
Flexible vertical antennas with BNC connectors sell for a few dollars.
Co-linear versions with gain are harder to find.
..... Phil
==========================
> I'm in need of an indoor omni antenna (actually two) in the 550-600mHz range.
> I've found a few with 5-9dBi gain from Italian manufacturers.
** 600MHz is a common radio mic frequency.
> I've found a few with 5-9dBi gain from Italian manufacturers.
Flexible vertical antennas with BNC connectors sell for a few dollars.
Co-linear versions with gain are harder to find.
..... Phil
Dave Platt
Jan 6, 2021, 12:37:33 AM1/6/21
to
In article <2C5JH.27093$rY1....@fx40.iad>,
antenna (which is a purely theoretical reference - no
perfectly-isotropic antenna can actually exist) they use the word
"isotropic".
In common usage, the term "omni" for an antenna usually refers an
antenna such as a monopole or dipole, which has a uniform radiation
pattern in a two-axis circular pattern, and is directional in only one
axis. I assume that's what the original poster is looking for.
Antenna gain is not always quoted w/r/t isotropic. Some manufacturers
quote gain that way (as dBi). Others quote it w/r/t a half-wave
dipole (as dBd).
Antenna vendors which quote antenna gain in "dB" (without telling you
what they're using as the 0 dB reference) are generally using dBi
numbers, because they're bigger by 2.15 and thus look better in the
ads :-)
Now, to the original request: as to needing antennas in the 550-600
MHz range (which is what I assume you're looking for since you said
"indoor")... that's still part of the US UHF-TV band, I think, and so
not one for which small narrow-band antennas would have much of a
commodity market, hence not many cheap commercial antennas available
(or so I suspect). Most coverage here is probably broad-band (often
untuned) receive-only antennas.
How much gain do you need? Receive-only, or is transmission required?
Can you satisfy your needs with something as simple as a wire whip of
the correct length, soldered to a BNC or similar connector, maybe with
a counterpoise wire attached to the ground shell, or a couple of
ground radials sticking out sidewise? Does it need to be pretty, or
child-safe, or capable of surviving the landing and attack of a
hyacinthine macaw? 50 ohm, 75 ohm, or something more exotic?
Clifford Heath <no....@please.net> wrote:
>> I'm in need of an indoor omni antenna (actually two) in the 550-600mHz range. I've found a few with 5-9dBi gain
>from Italian manufacturers. And while we are well versed in importing, we find their pricing....well, shockingly
>high. Any US ideas?
>>
>
>PSA: omni antennae do not have gain, because gain is always quoted wrt
>an omni (isotropic) antenna having gain of 0dB.
In my experience, when people want to refer to an isotropic or "0 dBi"
>> I'm in need of an indoor omni antenna (actually two) in the 550-600mHz range. I've found a few with 5-9dBi gain
>from Italian manufacturers. And while we are well versed in importing, we find their pricing....well, shockingly
>high. Any US ideas?
>>
>
>PSA: omni antennae do not have gain, because gain is always quoted wrt
>an omni (isotropic) antenna having gain of 0dB.
antenna (which is a purely theoretical reference - no
perfectly-isotropic antenna can actually exist) they use the word
"isotropic".
In common usage, the term "omni" for an antenna usually refers an
antenna such as a monopole or dipole, which has a uniform radiation
pattern in a two-axis circular pattern, and is directional in only one
axis. I assume that's what the original poster is looking for.
Antenna gain is not always quoted w/r/t isotropic. Some manufacturers
quote gain that way (as dBi). Others quote it w/r/t a half-wave
dipole (as dBd).
Antenna vendors which quote antenna gain in "dB" (without telling you
what they're using as the 0 dB reference) are generally using dBi
numbers, because they're bigger by 2.15 and thus look better in the
ads :-)
Now, to the original request: as to needing antennas in the 550-600
MHz range (which is what I assume you're looking for since you said
"indoor")... that's still part of the US UHF-TV band, I think, and so
not one for which small narrow-band antennas would have much of a
commodity market, hence not many cheap commercial antennas available
(or so I suspect). Most coverage here is probably broad-band (often
untuned) receive-only antennas.
How much gain do you need? Receive-only, or is transmission required?
Can you satisfy your needs with something as simple as a wire whip of
the correct length, soldered to a BNC or similar connector, maybe with
a counterpoise wire attached to the ground shell, or a couple of
ground radials sticking out sidewise? Does it need to be pretty, or
child-safe, or capable of surviving the landing and attack of a
hyacinthine macaw? 50 ohm, 75 ohm, or something more exotic?
Ralph Mowery
Jan 6, 2021, 12:49:57 AM1/6/21
to
In article <4bdfch-...@coop.radagast.org>, dpl...@coop.radagast.org
says...
1/2 wave dipole, some to a 1/4 wave vertical, and some to a wet noodle.
I never look at the gain given, but to the physical size of an antenna.
This is one case where bigger is usually better.
says...
> In common usage, the term "omni" for an antenna usually refers an
> antenna such as a monopole or dipole, which has a uniform radiation
> pattern in a two-axis circular pattern, and is directional in only one
> axis. I assume that's what the original poster is looking for.
>
> Antenna gain is not always quoted w/r/t isotropic. Some manufacturers
> quote gain that way (as dBi). Others quote it w/r/t a half-wave
> dipole (as dBd).
>
> Antenna vendors which quote antenna gain in "dB" (without telling you
> what they're using as the 0 dB reference) are generally using dBi
> numbers, because they're bigger by 2.15 and thus look better in the
> ads :-)
>
>
There seem to be many ways to state antenna gain. Some refference to a
> antenna such as a monopole or dipole, which has a uniform radiation
> pattern in a two-axis circular pattern, and is directional in only one
> axis. I assume that's what the original poster is looking for.
>
> Antenna gain is not always quoted w/r/t isotropic. Some manufacturers
> quote gain that way (as dBi). Others quote it w/r/t a half-wave
> dipole (as dBd).
>
> Antenna vendors which quote antenna gain in "dB" (without telling you
> what they're using as the 0 dB reference) are generally using dBi
> numbers, because they're bigger by 2.15 and thus look better in the
> ads :-)
>
>
1/2 wave dipole, some to a 1/4 wave vertical, and some to a wet noodle.
I never look at the gain given, but to the physical size of an antenna.
This is one case where bigger is usually better.
Phil Allison
Jan 6, 2021, 12:58:53 AM1/6/21
to
Dave Platt wrote:
------------------------------
Only if used vertically is it omni.
.... Phil
------------------------------
> In common usage, the term "omni" for an antenna usually refers an
> antenna such as a monopole or dipole, which has a uniform radiation
> pattern in a two-axis circular pattern, and is directional in only one
> axis.
** Dipoles are directional - the radiation or pick up pattern is in the shape of a figure 8.
> antenna such as a monopole or dipole, which has a uniform radiation
> pattern in a two-axis circular pattern, and is directional in only one
> axis.
Only if used vertically is it omni.
.... Phil
J.B. Wood
Jan 6, 2021, 12:30:10 PM1/6/21
to
On 1/5/2021 5:19 PM, Clifford Heath wrote:
> On 6/1/21 4:47 am, Klay Anderson wrote:
>
> PSA: omni antennae do not have gain, because gain is always quoted wrt
> an omni (isotropic) antenna having gain of 0dB.
Please look up what "isotropic" means and how it applies in antenna
> On 6/1/21 4:47 am, Klay Anderson wrote:
>
> PSA: omni antennae do not have gain, because gain is always quoted wrt
> an omni (isotropic) antenna having gain of 0dB.
theory. Then you'll be better informed. Sincerely,
--
J. B. Wood e-mail: arl_1...@hotmail.com
Clifford Heath
Jan 7, 2021, 3:15:20 AM1/7/21
to
On 6/1/21 11:30 pm, J.B. Wood wrote:
> On 1/5/2021 5:19 PM, Clifford Heath wrote:
>> On 6/1/21 4:47 am, Klay Anderson wrote:
>
>>
>> PSA: omni antennae do not have gain, because gain is always quoted wrt
>> an omni (isotropic) antenna having gain of 0dB.
>
> Please look up what "isotropic" means and how it applies in antenna
> theory. Then you'll be better informed. Sincerely,
Smart-arses trying to explain why omni doesn't actually mean omni...
> On 1/5/2021 5:19 PM, Clifford Heath wrote:
>> On 6/1/21 4:47 am, Klay Anderson wrote:
>
>>
>> PSA: omni antennae do not have gain, because gain is always quoted wrt
>> an omni (isotropic) antenna having gain of 0dB.
>
> Please look up what "isotropic" means and how it applies in antenna
> theory. Then you'll be better informed. Sincerely,
sigh. Some people are just born to be d*ckheads
J.B. Wood
Jan 7, 2021, 2:22:29 PM1/7/21
to
On 1/6/2021 10:15 PM, Clifford Heath wrote:
> Smart-arses trying to explain why omni doesn't actually mean omni...
> sigh. Some people are just born to be d*ckheads
>
An antenna is termed omni-directional if it possesses a circular
> Smart-arses trying to explain why omni doesn't actually mean omni...
> sigh. Some people are just born to be d*ckheads
>
radiation pattern in the azimuthal plane. The same pattern in the
elevation plane can be doughnut-shaped or something else. An isotropic
antenna is a theoretical construct with a spherical pattern in 3-space.
As its pattern is spherical, it's useful as a basis for comparison of
antenna gain (azimuth & elevation). Gain expressed in "dBi" designates
the units for this comparison. An isotropic antenna can be approached
in practice using 3 orthogonal electrically-small (in terms of a
wavelength) dipoles or loops (often called "magnetic" loops by ham radio
operators). Sincerely,
Rob
Jan 8, 2021, 2:18:27 PM1/8/21
to
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