Re: [softrock40] Antennas
- Failures can be fun when it just involves wire that can be reused. Mess
up a beam or a quad antenna and it's no fun at all. I know that from a
quad that kept collapsing even before I put it up. The Lightning Bolt
quad I have had up for over 26 years was the real fun part.
73 ... Sid.
On 04/01/11 01:36, John Williams wrote:
> You sound like a good bloke to sit down in a pub to enjoy a pint of ale
> as you tell stories of antennas that should not work - but did!
> Thanks for the entertaining reply,
> A yank named John - KE5SSH
> PSS - what tuners work well for QRP ops?
> On 1/2/2011 8:19 PM, Sid Boyce wrote:
>> If the weather is the problem with an outdoor antenna, a temporary
>> antenna in the attic or just slung over the roof top won't be the best
>> solution, but better than nothing.
>> When I first moved to this QTH I put a W8JK made of 300 ohm ribbon in
>> the loft and enjoyed many contacts between the UK and Stateside on 20m
>> and 10m with only 7W to a tuner, prompting one contact in New York to
>> repeat my working conditions and asking me incredulously to confirm.
>> The next antenna at the suggestion of a Stateside contact, a wire loop
>> slung over the roof and fed in the centre with 300 ohm ribbon to a
>> tuner. No measurement of length or check of symmetry was made. It wasn't
>> too good for Stateside but it worked a treat to the RAFARS net in Cyprus.
>> I made a magnetic loop from 3/8" soft copper tubing tuned with a
>> capacitor a little more wide spaced than a normal receiving capacitor
>> and with 7W on 40m before it arced over I was able to work as far east
>> as the Urals with it indoors on the landing upstairs. With soldering
>> iron in hand building a rig and listening to UK hams on 80m - using a
>> G5RV dog-legged around the eaves and down the garden, a discussion of
>> magloops was in progress, so I joined in and was simply recommended to
>> get some copper and build one, 2 days later it was on the air.
>> Everyone of my 80m Stateside contacts have been with a 13' diameter
>> magloop and 100W SSB. It was put together with 8 lengths of 28mm copper
>> and 45 degree elbows, tuned with a vacuum cap. Sadly it succumbed to
>> high winds, but I have in mind putting it up again when I figure it out,
>> perhaps placing the vacuum capacitor at the bottom of the loop this time
>> to lessen the wind resistance. I've done this with the current magloop
>> for 80/40 using 22mm copper and 8' in diameter.
>> The only complete failure I ever experienced was a 80m antenna wound on
>> a 3' length of 22mm diameter PVC tube with a top hat made of aluminium
>> about 6" or 8" in diameter. Absolutely nothing heard, then I put the 80m
>> radial I had run around the floor of the rooms upstairs into the antenna
>> socket and bingo! I called the editor of Practical Wireless who said he
>> was baffled as it worked for them before they published the article.
>> Antennas are fun and it's amazing what will work. It's a good idea to
>> check the web/ARRL pubs, solutions are endless.
>> 73 ... Sid.
>> On 02/01/11 20:20, Mike WA8BXN wrote:
>>> I have a 130 foot dipole fed with ladder line and use a tuner. Considering
>>> the weather, I would pick a length for the dipole that is a bit less than
>>> the distance between two easy to use supports (trees) you have. I would try
>>> make it at least 100 feet long if you want good results on 80 meters. Of
>>> course, getting your antenna up as high as possible is generally good. Still
>>> you can get good results with a low antenna for now. Get it up at least high
>>> enough that deer (or cows) won't run into it! A balanced line tuner would
>>> be best, but any tuner with a balun at the tuner going to the ladder line
>>> will do.
>>> Just about anything along these lines will do better than an antenna in the
>>> attic. I get good results with my antenna at about 20-25 feet (it slopes a
>>> bit) running 5 watts.
>>> 73/72 - Mike WA8BXN
>>> -------Original Message-------
>>> From: John Williams
>>> Date: 1/2/2011 2:57:57 PM
>>> To: email@example.com<mailto:softrock40%40yahoogroups.com>
>>> Subject: Re: [softrock40] Antennas
>>> Given that I can go outside, and given that I want to stay around 20-30
>>> watts, is there an optimal single antenna design (with or without a tuner)
>>> to run 80-20meters at a fairly low wattage?
>>> I will also probably experiment with digital in addition to phone. Just
>>> installed some psk31 programs from the Ubuntu app store and they look
>>> interesting to play around with. This will be fun!
> Yahoo! Groups Links
Sid Boyce ... Hamradio License G3VBV, Licensed Private Pilot
Emeritus IBM/Amdahl Mainframes and Sun/Fujitsu Servers Tech Support
Senior Staff Specialist, Cricket Coach
Microsoft Windows Free Zone - Linux used for all Computing Tasks