Higher Discone+better coax

[bianco99]

Hi,
We planned to move our discone higher. Now it has been installed on 20feet pole (2 story house) and we would like to move the discone higher to 38/40 feet.
What do you think? Is it gonna be an upgrade?
At the same time we wanna change the H155 we already have with the Messi and Paoloni ULTRAFEX 10.
Most of the listening would be done either on the airband or 446 with an SDR PLAY.

Kind regards,

 

[dlwtrunked]

Height is the main factor. You may receive ground stations farther away and may notice an effect on aircraft farther away if you have nearby hills. (Note: Height and better coax for a setup like yours probably are important in that order--but do not skip on either.)

 

[bianco99]

Height is the main factor. You may receive ground stations farther away and may notice an effect on aircraft farther away if you have nearby hills. (Note: Height and better coax for a setup like yours probably are important in that order--but do not skip on either.)

The main concern are lightning:
There would more chances by having the pole higher?

 

[vagrant]

That Messi and Paoloni is no joke and should serve you well, but...but I would get your discone above the roofline first and you may be happy with that result. If there are other buildings nearby, you would want the antenna above that in order not to shadow your receive direction.

The apex of my neighbors roof line is at 27' AGL (Above Ground Level). The base of my antenna is at 30' AGL. I could put it higher, but I am not trying to receive terrestrial stations just over the horizon. Your needs may be different.

Also, if you are not using an FM broadcast filter inline on your coax, you should.

 

[Ubbe]

At 446MHz and for each 10ft the attenuation are
0,27dB for Ultraflex10
0,7dB for H155

Using H155 and making the pole 40ft would give 4.2dB loss at 446MHz.
Going for Ultraflex10 would make it a 1,6dB loss. It's a 2,6dB difference.

The H155 costs something like $25 for 60ft and Ultraflex10 $120
But you can also add $8 worth of 20ft H155 coax to your existing one and add the cost of connectors and seal them with emulgating rubber tape.

Look at the dBm signal strength value for your SDRPlay how much difference that 2,6dB will do, if it's worth the extra cost. Difference will be less the lower you go in frequency.

For that $100 difference you can get a high quality LNA and broadcast filters and still save money and have no loss at all and instead get a boost of the signal.

/Ubbe