Rick,
You found it. And yes, I do understand that it will be barely
functional at 60 M. It does give me 10, 15, and 20 M so that would be
nice break in the driving. The antenna only needs the coil for 60 m, 40
M, 30M and barely (1 turn) for 20M, I am going to think about your
suggestion for 40. But it is collapsible and I started with the
premise that if I am going to the TT Fleamarket, I should bring a radio.
I have the Argosy, and it works, I can find picnic benches between
here and there. This antenna seems like a reasonable compromise and the
Argosy dunna work so well without one.
As to radials, I was thinking about 12 radials about 15 ft long.
Attach 2 sets to each side of the base with a wing nut. Again, it isn't
ideal, but should work reasonably well. I was thinking about getting a
15 or so 40 or 60 d nails to use as anchors. Maybe 20d nails might be
better, or at least cheaper and easier to insert into the ground. I
could crimp large rings on the outer end of each radial and nail it
down, so to speak. At any rate, I do believe that 12 to 16 radials is
the minimum to make the antenna play nice.
At the very least,it is an interesting project.
John / WA1JG
On 4/4/2012 2:16 AM, Rick - DJ0IP / NJ0IP wrote:
> John,
>
> The link didn't work for me, so I googled it and found another page.
> Dunno if it is the same, but I think it is.
> http://ad5yu.wordpress.com/2007/01/07/ad5x-portable-vertical-antenna/
>
> My comments are based on the risky assumption that this is the same antenna
> you are thinking about!
>
> It's a 10' whip with a center loading coil.
>
> It's gonna work pretty well on the high bands, but it won't be so great on
> the low bands.
> For mobile we have a legal limit for the length (I think 10'), but why would
> you want to limit the height of a portable antenna to just 10' and then add
> a lossy coil?
> Even on 20m the quarter wave is 16'.
>
> Maybe I'm biased because most of my operations is on 40m and that antenna
> just is not going to be a great 40m antenna.
>
> I much prefer the telescoping fiberglass pole method. They go up and down
> in less than one minute. You can have a full size 40m vertical (33')
> without even having to guy it (if it is only temporary). Just have separate
> quarter wave wires for each band you want to operate.
>
> In fact for 40m, since daytime operation is more close in operations, run
> your 33' of wire only half way up a pole, then slope it back towards the
> ground as if it were one half of an inverted vee. Tie it to a ground stake
> about 20' away. Now you will have a MUCH stronger signal for NVIS type of
> work.
>
> NOW for low bands, Phil has put forth some outstanding suggestions for
> matching 43' verticals on 80 and 160. His suggestions here are some of the
> best I've ever seen.
>
> FINALLY, I started out in the early 1970's using home-brew mobile whips with
> coils in the middle. Once I switched to the long fishing poles (now days,
> there are much better purpose-made poles for ham radio), I never looked
> back. There is a huge difference.
>
> The old adage, make your wire higher and longer is still true (in general).
>
> 73
> Rick, DJ0IP
>
> -----Original Message-----
> From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
> On Behalf Of John
> Sent: Wednesday, April 04, 2012 12:03 AM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] Using an Argosy in the field
>
> John,
>
> My current plan is to build a vertical that can collapse into short
> sections. It is a design by Phil Salas - AD5X and uses a 10 ft telescoping
> whip at the top and covers 60-10 meters, without a tuner. I have had good
> luck with verticals and even though this is a 1/4, with some radials I
> think I will be in good shape I placed the address of the article at the
> bottom of this note if you are curious.
>
> Also planned is the acquisition of a light sealed battery probably about
> 7 ah. The Argosy can run from 5-50 watts so it gives me some play room.
> And hopefully my choice of battery size will not be too limiting.
>
>
>
> John / WA1JG
>
> http://www.ad5x.com/images/Articles/VerticalRevH.pdf
>
> On 4/3/2012 4:49 PM, John Peters wrote:
>> Sent from my iPhone
>>
>> On Mar 28, 2012, at 5:21 AM, "Rick - DJ0IP / NJ0IP"<Rick@DJ0IP.de> wrote:
>>
>>> John,
>>>
>>> The lynchpin to having a good signal when operating low power
>>> portable, is a good antenna.
>>> Some people take a great rig, run it at reduced power on a crappy
>>> antenna (i.e., mobil whip mounted to a ground stake), and wonder why
>>> they don't work anybody.
>>>
>>> Wire can be a wonderful antenna, but you have to get it up high in the
> air.
>>> That's why I always took a telescoping fiberglass pole with me.
>>> In the early days they were just 8m long.
>>> Later there were some purpose-built poles for ham radio that were 10m
> long.
>>> Today you can get them in even stronger quality in lengths of 12m or 18m.
>>> In fact they even come as long as 26m but that's a bit overkill for a
>>> one-man expedition.
>>>
>>> For Field Day I always ran a doublet, with each leg 13m long, and fed
>>> with
>>> 300 Ohm Openwire.
>>> I had a tiny little MFJ Matchbox (T-filter), with a built in Balun.
>>> The Balun was great for 5w QRP or 20w, etc., but I burned it up
>>> running 100w.
>>> Had to re-build it, then never tried 100w with it again.
>>>
>>> For my normal excursions I had a special lightweight 3-band dipole:
>>>
>>> - made of thin Teflon-insulated stranded copper wire (I guess about
>>> AWG 22 or so)
>>> - cut for 20m, insulator, more wire for 40m
>>> - 2x short jumpers for jumping the insulator between 20m and 40m
>>> segments, for 40m operation
>>> - 2x short stubs with alligator clips to extend the antenna for 15m
>>> operation (6 inches on each end)
>>> - fed with about 50' of RG-174 (YES, THE THIN STUFF).
>>> - A ball of twine for tying off the ends
>>>
>>> Twine was cheap and disposable if it got too tangled. Ends tied off
>>> to trees, or if nothing else, simply to stakes in the ground.
>>>
>>> The thin RG-174 is sufficient and loss is really not bad for short
>>> runs at those frequencies. The loss is worse if you use heavier
>>> coax, and then fail
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