Topband: GAP Vertical Question

Sun Dec 16 16:16:15 EST 2012

Charlie, your starting to sound like the other guy; trying to interpet my 
posts and spin to your benefit and getting demeaning in the process. Give me 
a bit more credit than that...OK... I know a bit about antennas.

To be a bit more clear the tuner was always connected to a ground.. First to 
just an 8' rod and then the #6 copper ring around it with the 60 radials. 
Even the coax was ferrite decoupled as I was far ahead of the pack with 
their use having worked on the Tempest program as already mentioned.

Carl
KM1H

----- Original Message ----- 
From: "Charlie Cunningham" <charlie-cunningham at nc.rr.com>
To: "'Carl'" <km1h at jeremy.mv.com>; "'Richard (Rick) Karlquist'" 
<richard at karlquist.com>; "'Donald Chester'" <k4kyv at hotmail.com>; "Tom W8JI" 
<w8ji at w8ji.com>
Cc: <topband at contesting.com>
Sent: Sunday, December 16, 2012 12:06 PM
Subject: RE: Topband: GAP Vertical Question

> Well, Carl
>
> Your experience with your 6-wire cage vertical - 1/4 wave on 80 - AND 1/2
> wave on 40 was not very enlightening or satisfying and led to some serious
> misunderstanding!!
>
> When you removed the radials - OF COURSE it was a "DUD" on 40 -if you 
> just
> left the coax feed in place!!   You were trying to end-feed a 1/2 wave
> resonant antenna on 40m from coax - you must have a heck of a tuner, but 
> the
> VSWR and mismatch loss were so high that you weren't delivering much of
> anything to the antenna!! Most of your power was being dissipated in 
> heating
> the coax operating at very high VSWR!!   You could have turned it into an
> excellent 40m antenna if you had end fed it through a 40m 1/4 wave open 
> wire
> ladder line or fed it from the top end of a 40 m parallel tuned circuit
> (cold-end grounded, of course) tapped for a match to your 50 ohm coaxial
> feed line. If it still worked on 80 without the radials, there must have
> been a fortuitous length of coaxial shield to supply the missing "lower 
> 1/2"
> of the antenna! But you solved the problem without ANY  understanding and
> put up 4 40m elements at 120 feet! The problem was NOT a "GROUND 
> PROBLEM" -
> but was rather one of "operator head-spacing"!  There must have been a
> hellacious VSWR on that COAX trying to feed that 1/2 wave vertical cage at
> the end with no radials. Your understanding of antennas, resonance, 
> matching
> and grounding seems to leave a LOT to be desired! Perhaps some reading and
> study would help!
>
> Regards,
> Charlie, K4OTV
>
> P.S.  A 1/2 wave vertical does NOT need a "salt water marsh" under it to
> work VERY well!  In fact a vertical 1/2 wave in free space also works very
> well!!
>
>
> -----Original Message-----
> From: Charlie Cunningham [mailto:charlie-cunningham at nc.rr.com]
> Sent: Sunday, December 16, 2012 9:16 AM
> To: 'Carl'; 'Richard (Rick) Karlquist'; 'Donald Chester'
> Cc: 'topband at contesting.com'
> Subject: RE: Topband: GAP Vertical Question
>
> Good morning, Carl
>
> Well, a 1/4 wave vertical absolutely requires a "ground plane"!! A 
> vertical
> 1/2 wave - not really!
>
> It seems that, in  your observations, you are mixing the two? Any 1/4 wave
> vertical absolutely does need an "image plane" to work against!
>
> Charlie, K4OTV
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Carl
> Sent: Saturday, December 15, 2012 7:46 PM
> To: Richard (Rick) Karlquist; Donald Chester
> Cc: topband at contesting.com
> Subject: Re: Topband: GAP Vertical Question
>
> My own experience with 1/2 wave verticals is that they certainly do 
> require
> a good ground.
> Maybe a rod in a saltwater marsh is sufficient but not in many other 
> cases.
>
> Examples:
>
> A Shakespere CB whip in my 66 Corvette which was advervtised for 
> fiberglass
> cars. It couldnt be heard a mile away with 4W. I added "radials" from the
> base on the rear deck to the frame on all 4 corners and then it worked 
> much
> better. This was back in the late 70's for several years.
>
> A 80/40M 6 wire cage vertical, a full quarter wave on 80 and hanging from 
> a
> tall pine tree branch at a prior QTH. With 60  65-70' radials it was
> competitive on 80 and on 40. With the radials removed it was a dud on 40.
> With another phased 1/4 wave on 80 it delivered the gain and F/B expected
> and 40 was improved with a pair of figure 8's but still not up to
> expectations. A 4el 40M KLM at 120' fixed that.
>
> Carl
> KM1H
>
>
>
> ----- Original Message -----
> From: "Richard (Rick) Karlquist" <richard at karlquist.com>
> To: "Donald Chester" <k4kyv at hotmail.com>
> Cc: <topband at contesting.com>
> Sent: Saturday, December 15, 2012 3:58 PM
> Subject: Re: Topband: GAP Vertical Question
>
>
>>
>>
>> On 12/15/2012 12:03 PM, Donald Chester wrote:
>>>
>>> From: charlie-cunningham at nc.rr.com
>>>
>>>   Could you support a vertical 1/2 wave for 160 with aballoon?
>>> You could end -feed it at the base through a 1/4 wave of 450 ohm
>>
>>> But feeding a half wave vertical with the base near the  ground
>> > still  results in substantial ground losses without a radial system.
>>
>>> Don k4kyv
>>
>> And this statement is based on what?  Publications, measurements,
>> modeling?
>>
>> I have built a number of 1/2 wave verticals without radials and
>> compared them to 1/4 wave verticals with radials.  They are
>> indistinguishable in performance and certainly do not exhibit
>> substantial ground losses AFAIK.  The PAR electronics 1/2 wave end fed
>> antenna seems to have a good reputation, unlike some GAP verticals.
>>
>> However, I don't recommend feeding it through 1/4 wave of 450 ohm open
>> wire line.  I just use an LC matching network.
>>
>> Rick N6RK
>> _______________________________________________
>> Topband reflector - topband at contesting.com
>>
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>
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> Topband reflector - topband at contesting.com
>
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