Topband: Elementary Inverted L questions

[N4ZR]

Thanks to everyone who has replied so far, and apologies - I did a lousy 
job of describing the antenna.  First off - I set out to make it 1/4 
wave (approximately 128 feet) long, and the starting length of wire 
(what I actually put up) was 140 feet.   Vertical portion is about 55 
feet, and the horizontal part is more or less level. The feedpoint choke 
is wound on a #43 core (I think), which may make it a bit more 
credible.  The measured minimum SWR is 2.2 at 1925 KHz, and resonance (X 
crossing zero) is at 1983 KHz.  All measurements made at the base of the 
antenna

Now here's the part I *really* don't understand - at X=0, the R measures 
119 ohms. Working from memory, I think the old L was resonant about 1875 
KHz, and the R was on the order of 35 ohms, which I was told made sense 
for a quarter-wave with a lossy ground plane.  The new numbers make no 
sense at all to me.

73, Pete N4ZR
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On 3/25/2021 12:26 PM, Artek Manuals wrote:
> Technically the insulation should electrically lengthen the antenna 
> about 1.5-2 % (lower the frequency)
>
> As Wes said the dimensions would be helpful. is the flat op horizontal 
> or does it slope down if it slopes how low is the far end?
>
> I dont think 17 turns of RG400 is doing much for you on 160M but with 
> a ground mounted radials (IMO) not likely needed...what is the "R" at 
> X=0.
>
> �Are you measuring R+jX at the antenna or at the shack end of the 
> coax? How long is the coax
>
> Dave
> NR1DX
>
>
>
> On 3/25/2021 11:54 AM, Wes wrote:
>> How long is the vertical section?� The insulation should have minimal 
>> effect.
>>
>> Wes� N7WS
>>
>>
>> On 3/25/2021 8:07 AM, N4ZR wrote:
>>> I have been trying to replace my inverted L, which broke a few weeks 
>>> ago, and am having all sorts of puzzlements. Please be kind - I was 
>>> a history major.
>>>
>>> 1.� The inverted L broke at the turn, so I went looking for sturdier 
>>> wire.� I wound up with some #14 insulated recommended by our local 
>>> RF maven, and put up 140 feet initially, figuring I would prune it 
>>> *up* into the CW part of the band.� Imagine my surprise when it 
>>> showed up resonating at 1977 KHz (on an AA-55 Zoom).� Does 
>>> insulation have such a profound effect on velocity factor?
>>>
>>> 2.� My feedpoint arrangement has 17 turns of RG-400 as a common mode 
>>> choke, with the radial field connected to the RG-400 shield at the 
>>> antenna end.� Initially I tried measuring the resonance without the 
>>> radial connection.� No resonance and infinite SWR. I connected the 
>>> radial field (8 X 70-foot radials on the ground) and that's when I 
>>> saw the 1977 KHz resonance (X crossing zero). SWR at minimum was 
>>> above 2:1.� Does this make sense?� I know the radial field is 
>>> inadequate for good performance, but...
>>>
>>
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