[Elecraft] Elecraft AX-1 Whip Antenna

Wed Sep 21 23:31:18 EDT 2022

Why would I replace the wire with a resistor?  I was talking about 
replacing the AX1 with a resistor and keeping the wire.

I have no doubt that an AX1 without a wire hears better than a resistor 
without a wire, but that's mostly because the resistor provides a better 
match and can't rely on body capacitance or the coax shield.

If the AX1 was less expensive I'd buy one and do the tests.  I may be 
totally wrong, but I still say that ANY tuned short whip with a 
counterpoise is doing most of the radiating from the counterpoise.

73,
Dave   AB7E

On 9/21/2022 7:59 PM, Wayne Burdick wrote:
> Dave,
>
> I've done many variations on whip antenna tests.
>
> A resonant 4' whip with or without a counterpoise is on a different planet from a resistor. If an AX1 were listening in on this conversation, it would challenge you to a duel, with live ammo :)
>
> In fact the counterpoise is absolutely required for transmit, but you can get away without it on receive, where body capacitance to ground alone will suffice, even on the HF bands.
>
> Try this test: Go outdoors and connect an AX1 (or equivalent) to the antenna jack of any 20 meter receiver. With r without the counterpoise You'll get of noise, lots of signals.
>
> Now replace the wire with a resistor.
>
> Nothing.
>
> QED....
>
> Wayne
> N6KR
>
>
>
>
>
>> On Sep 21, 2022, at 7:29 PM, David Gilbert <ab7echo at gmail.com> wrote:
>>
>>
>>
>> Well, the reason I mentioned the 50 ohm resistor is that a year or so ago somebody on this reflector mentioned that he did a direct comparison between an AX1 with the recommended 13 foot wire counterpoise and with no counterpoise at all.  I don't remember for certain but I think he said he used the RBN.   I do remember that he said the difference in signal strength was about 30 db.  For grins I used EZNEC to model a single 50 hm resistor 15 feet off the ground with and without a 13 foot wire hanging from one end of it.  I got 30 db difference in calculated signal strength.
>>
>> I am by no means claiming that is a definitive or even relevant test ... I just think it would be interesting to actually do an empirical comparison.
>>
>> It is my opinion, however, that most of the radiating on an AX1 (or any other short loaded whip) is being done by the counterpoise wire and/or the shield of the coax.  The coil and whip are matching aids.  If so, it's possible that a resistor would accomplish the same thing.  ;)
>>
>> As I said, I'd be willing to do the comparison if anyone is willing to lend me an AX1.  I'd be happy to be proven wrong.
>>
>> 73,
>> Dave   AB7E
>>
>>
>>
>> On 9/21/2022 6:46 PM, john at kk9a.com wrote:
>>> Thomas Schiller, N6BT once wrote an article titled "Everything Works". In
>>> the article he discussed how he worked all continents on CW (a mode that you
>>> can actually hear) using a light bulb antenna during the ARRL DX contest.
>>>
>>> The AX1 appears to be a 45" whip with a base inductor made of 20AWG wire. I
>>> am not sure what is inside the base, if anything, to bring the impedance up
>>> to 50 ohms. With some sunspots, I am sure that it is fun for pedestrian
>>> mobile use which is what it's designed for. A 1/2wl dipole or 1/4wl vertical
>>> will be a much better radiator.
>>>
>>> John KK9A
>>>
>>>
>>>
>>>
>>> David Gilbert ab7e wrote:
>>>
>>> A comparison to any other antenna would be useful.  A comparison to a 50
>>> ohm resistor with a similar counterpoise wire would be even more useful
>>> as a baseline measurement.  If anyone wants to lend me their AX1 I will
>>> do that.
>>>
>>> 73,
>>> Dave   AB7E
>>>
>>>
>>> On 9/19/2022 10:33 AM, Ron Gruner wrote:
>>>> I've been impressed by how well my little AX-1 whip antenna performs on 20
>>>> meters. Here's a photo of the rig: https://gruner.com/k4rhg/andover_ma.png
>>>> and the propagation map:
>>> https://gruner.com/k4rhg/wspr_2watts_sep16_2022.png
>>>> A friend, Derek Rowell (AK1WI), gave me a two-watt WSPR kit he had
>>> designed
>>>> -- easy and fun to build. I connected the unit to the AX-1 sitting in a
>>>> window sill facing west and strung the out-of-the-box counterpoise over a
>>>> lamp shade and bed headboard. No idea what the SWR is, but it must be
>>>> pretty good.
>>>>
>>>> I immediately began receiving propagation reports and within 24 hours had
>>>> reports from 240 unique stations. The farthest was VK5ARG (17,276 km) with
>>>> a SNR of -21. Even though the window faced the west, propagation into
>>>> Europe was strong with SV9KI (7,800 km) reporting -26 SNR. The
>>>> propagation report is from http://wspr.rocks/  <http://wspr.rocks/>
>>>>
>>>> I've found that WSPR is a great way to evaluate antennas. The AX-1 seems
>>>> to be performing very well.
>>>>
>>>> 73,
>>>> Ron Gruner
>>>> K4RHG
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:Elecraft at mailman.qth.net
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> Message delivered to ab7echo at gmail.com
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Elecraft at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to n6kr at elecraft.com