Stacked FM dipole

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Ken
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Stacked FM dipole

Post by Ken »

I woner wich stacked dipole give me the higest gain, most output power?

I wanna stack 4 dipoles, max 1kW transmitter.

Alt 1. http://www.pcs-electronics.com/stacked- ... p-327.html

Alt2. http://www.pcs-electronics.com/stackabl ... -1481.html

And if I use Alt 2, what "splitter" do I use for the antennas?
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pcs
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Post by pcs »

Hi there,

it depends what polarization you prefer.
If you're OK with vertical only, vertical dipoles will give best results.

Those antenas that are in horizontal or other orientation will
experience some loss of signal compared to those in vertical.

Some prefer circular polarization as it covers both vertical
and horizontal antennas equally, however the gain is smaller than with
vertical polarization at the transmitter and receiver.

Google it up, I suck at explaining this.

Many small stations just use vertical polarization. Big stations
often use circular. You can use the same combiners for both antenna
types listed.
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Ken
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Post by Ken »

Thanks Marco, I will Google for more info.

But if I choose circular antennas, what antenna splitter, harnest cable do you rekomend when I use four antennas. In other words what more than the four antennas and the coax from transmitter do I need.
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pcs
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Post by pcs »

Use the harness that is listed under that vertical dipole.
You have either 2-way or 4-way splitter.
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
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pcs
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Post by pcs »

I just spoke to a guy who works with these antennas a lot, some very usefull hints:

1. Vertically polarized dipoles: Best range, worst multi-path problems (reflected and
direct wave interfering

2. Horizontally polarized dipoles: wonderful for solid coverage of immediate
area close to the antenna tower, less range than vertical polarization.

3. Reduces the problem of multipath (see point 1 for vertical dipoles).
But requires more power for same range.

It would appear circular is the best, but also the most expensive solution as you
require more power to cover same range.

What is the problem of multipath? You can have lots of signal at some point,
but reception will still break-up due to interference of two signals.

Hope this helps.
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
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