discone antenna

[bobsedlak]

I am currently using a discone antenna for my radio shack pro 197 scanner.I am in caseville Michigan on Saginaw Bay.I would like to use the same antenna for my icom base marine radio so I can talk to the to people on the lake before I go fishing.Is this possible.One guy told me I could another radio guy said no you need to get another antenna a discone or a tram1600-hc would work well. Does anybody have any ideas for me.

 

[ka3jjz]

While possible, the optimum would be to have a separate antenna. If for no other reason, one day you will be in a hurry, have your scanner on while you transmit, and wonder why the scanner's front end is burned out.

Be sure to space the marine antenna far enough away (at least more than 1/4 wave) so the discone doesn't interact with it. 73 Mike

 

[bobsedlak]

thanks Mike I am new at this like real new so how far is a 1/4 wave in inches and feet.Also do you know which antenna would work best for the marine radio,the discone or the tram1600-hc thanks bob

 

[ka3jjz]

Ask about marine antennas in the marine forum - I'm not at all familiar with that service. However, discones have virtually no gain because they're so broadbanded; I kinda doubt they'd be a good choice in the maritime service as a transmit antenna in any case.

The typical formula for a quarter wave is 234/f(mhz) - I would figure, at a minimum, for the center of the marine 156-157 mhz area and go from there. The measurement comes out in feet. Many will also tell you that vertical separation is as important as horizontal. So putting the marine vertical higher than the discone also counts. Bottom line, the more separation between the 2 antennas, the better.

The marine VHF channels, with their respective frequency pairs, are defined here...

Marine VHF Channels - The RadioReference Wiki

73 Mike

 

[bobsedlak]

thanks again for your help I am going over to the marine forum and check that out

 

[Rick_Harvey]

The Radis Shack Discone antenna we have at the shop( the bigger one), is rated 25-1000 MHz. We use it to receive and transmit on any frequency, and it has no swr. It is unity gain, so the range is low, but it works great as a universal antenna