Grove antenna?

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bobruzzo

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Someone is selling this Grove scanner antenna for $25. I happened to run across it. I have been using a similar antenna home built for aircraft. It was a vertical dipole fed with 75 ohm rg6 coax. Worked superb. However it was damaged in high winds and rain somehow got into the coax. Now it;s in the junk heap. So I am looking at this antenna which is commercially made and will withstand elements better than my homebrew one. Is anyone familiar with those Grove antennas? I remember them from early 80's but never owned one. I am tempted to get this antenna even though it's a very long ride from where I live. Prob an hour away.
 

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Ubbe

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It uses a 300/75 ohm balun transformer. The antenna will have a wide spead of impedance over the frequency ranges and the balun will probably help to smooth that out. But at the cut frequencies, where it should work best, the impedance are low in the 75 ohm range and the 4:1 transformer will reduce the signal level 4 times. The loss will be less at other frequencies where the impedance are higher so the signal level will even out, to be bad at all frequencies compared to a normal dipole without a 300 ohm to 75 ohm transformer.

/Ubbe
 

bobruzzo

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It uses a 300/75 ohm balun transformer. The antenna will have a wide spead of impedance over the frequency ranges and the balun will probably help to smooth that out. But at the cut frequencies, where it should work best, the impedance are low in the 75 ohm range and the 4:1 transformer will reduce the signal level 4 times. The loss will be less at other frequencies where the impedance are higher so the signal level will even out, to be bad at all frequencies compared to a normal dipole without a 300 ohm to 75 ohm transformer.

/Ubbe
Haha I guess it's really not worth the 1 hour drive to the middle of nowhere for this antenna!
 

ladn

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I've made a few OCF dipoles based on the RR Wiki design and have been pleased with the performance. One of them is made out of anodized 1/2" aluminum tubing and a Schedule 40 PVC pipe "T". It lives in the rafters of my garage and serves my garage scanner. Another one is made out of insulated, stranded, wire and is on the wall in my office for a handheld scanner. I'm not interested in DX scanning with these, just local stuff and they were an easy solution.
 

N9JIG

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I had one of these in my attic at the old house and it worked great. I wish I had recovered it to use it here but it was way off in the corner and covered with insulation (they redid the blown-in insulation a few years before we moved).

I recall it being supurb on VHF so I used it on my Plectrons.
 

Arkmood

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Is anyone familiar with those Grove antennas?
Yes. Used the referenced Grove antenna for years in balcony/attic setups, with many different receivers. One of the nice features with this particular antenna was its portability - the two elements had a foldown/snapinplace design and the feedpoints were furnished with wingnuts for easy feedline attachments. The large capture area added to multi/all band purposes, it did a very good job on 27-1300mhz.... and analog/1G cellular 800mhz - (a sizeable consideration when scanning in the 90s). If used outdoors waterproofing is important -in one setup remember the feedline became waterlogged all the way to the receiver (Pro 34w/800mhz converter) without it.
 
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