VHF antenna for 147-800 Mhz monitoring

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RRR

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I have tried and failed with the Austin Spectra antenna. Not only did the cheap center contact tin piece break off (it lost it's "spring" after I first installed it, and I didn't crank it down hard) but the coax inside the spring base (plain coax, with a spring over it) had broken as well, after going thru 4 car washes.

I have a good Motorola VHF long base load antenna I have since stuck up there, and of course it does fine on the VHF frequencies. I usually monitor the 154-161 MHz band, so that's no issue, but there are some 700-800 Mhz systems throughout Georgia I like to monitor when I get near those areas as well (I have the scanner GPS set to open them and close them at approx. 5 miles outside the counties they are in) ...BCD996XT, by the way.

I do not monitor any 400Mhz systems, just VHF and 700-800 Mhz.

My question is, what appreciable difference will I get (or not get) on receive with the VHF antenna for monitoring the 800mhz systems v/s the Austin (when it did work)? Would it be worth it for me to install an 800Mhz antenna also, in unison with the VHF one?

This is strictly for transmit only.

Thank you!
 
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jackj

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"Jack-of-all-trades", that's what you are looking for only in the antenna version. What you're going to find is a "Master-of-none". No VHF antenna, especially a gain-type, is going to work well at UHF frequencies. You could try feeding both a VHF and a UHF into the same coax, the frequencies are far enough apart so that they shouldn't affect each other too much. Your best bet would be to buy an antenna that has traps (coils) in the rod that would serve to de-couple the VHF (top portion) from the UHF (bottom portion) on UHF. Good luck.
 

RRR

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...and take it off when you go through the car wash!

Easier said than done on a service truck. Besides, none of the other antennas have to be removed, they spring back about 80 degrees and still work fine. (I know I stated car wash, mainly drive thru's though)

Do I have to feed the antennas together at the scanner, or can I do it somewhere else in the feedline?

Thanks for the responses.
 

RRR

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Ok, so scrap the combiner, would I be better off with a good 800Mhz antenna only, instead of a VHF antenna only? I know my VHF signal would suffer, but I don't really try to monitor more than a county away. The 700-800 stuff is what I have historically had trouble pulling in, even with the multiband antenna.
 

prcguy

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I believe the old Motorola long coil VHF antennas were 5/8 wave just like the A/S versions. Any 800 reception with one of these would be coincidental and when you get away from the strong signal area, reception will probably suffer.

Why not get a Larsen Tri-band or Maxrad BMXSCAN1000? They both work about the same on VHF/UHF/800 and are only around 18" tall.
prcguy
 

teufler

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I monitor here at home with an 800 mhz antenna. its a 5/8 wave over a 5/8 wave over a 1/4 wave. its about 21" tall. works for vhf and very good on 800. DPD Productions - Scanner, Aviation, NOAA, Low-Band, 700 MHz Public Safety, Base & Mobile Radio Antennas for Commercial & Hobbyist Applications
several antennas are shown here, There is a real low profile model also. Sort of a black cone like antenna. Some of the local highway patrol have an antenna like this. The 21" tall version, can be used as a base antenna aw well as a mobile antenna .
 

RRR

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I meant "for receiving only" in the first post, sorry
 
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