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Re: LF: Re: Keeping the smoke in

To: [email protected]
Subject: Re: LF: Re: Keeping the smoke in
From: "Laurence KL1X" <[email protected]>
Date: Fri, 03 Feb 2006 04:45:49 -0900
Delivery-date: Fri, 03 Feb 2006 13:46:31 +0000
Envelope-to: [email protected]
In-reply-to: <020320060153.24772.43E2B7A400019564000060C422007358340B97010D0A020E06979D0E03@comcast.net>
Reply-to: [email protected]
Sender: [email protected]
Yep your absolutely right about safety Warren - Kids, dogs and the local Skunk/squirrel population stayed away but I did notice that the odd California wren had left its mark inside the coupler reducing the insect population around the Caps.

For those that could read I had RF exposure warning signs in quite a few location. Being near the 5th tee and wardward ball finders often sojourned into the loop area so official signs "you are entering a zone etc" were a necessity. I saw one golfer, using his 7 iron actually reach up and try to snag the horizontal section of the loop - Doh.. for the next open QTH I going to put up Actung!! Minefield!! signs. No such a problem here being in a fully fenced "compound" garden which makes Gitmo look like an open park.


Coupler  -
I used a double box method - My coupler weighs close to 60 pounds with lots of Sangamo G2,3's and 4's to share the current load and not able to mount on a tree so it sat just off the ground on a sloping plinth with the lid of the Rubbermaid box open about 1 inch at the back - the Rubbermaid was covered by a littleframed housing some 4 ft cubed with a sloping poly type corrugated roofing. Heating was most noticeable during summer when we get those 100 plus days with no wind but in the winter I have not seen the hot end side of the primary winding get over say 110F (?) - this is with the Decca running full whacko for days on end. I cant find the email with the component temperatures I put out a few months ago but the hottest part of the toroid was turn 1 of 17 on the primary #12 goiing to the 50 ohm connector

Ive put a new shot of the coupler on the web site.

http://myweb.cableone.net/flow/copper3.jpg

Note that even with #4 THHN secondary it gets just above ambient warm with around 50A RF flowing thru it! Hottest (wam) components on the loop side are the 1/4 inch threaded feed thru rods on the ceramic standoffs where the huge Lowe copper lugs are connected to the paralleld loops

...and as to which I prefer - the vertical or loop. For operational stability, unattended and no auto tuning and no stress at the +1Kw +24 hour op level it has to be the loop. I didnt touch mine for weeks on end and didnt lose sleep in unattended operation. I didnt watch the phase meter go left and right as the wind blew but it rarely caused an increase in guard current on the Decca. I just couldnt have dont that with my skills with the vertical - I longest I left the Alaksan 110 footer was a week and I went gray(er) worrying about off tuning, high SWR and unwanted central heating in the house. I have to say the loop suits my laxidazical (?) engineering methods too - Sling up some insulated wire over the trees limbs - not too much insulation issues, dont even worry too much about spacing or where the wires flop around around too much and you can still get "out" to some degree. Though there is still Voltage about in the coupler and on the wires it seems to me a less problematic soltiion. Now give me 5 acres in open country and youll see another answer of course and thats what I have planned in my mind for a retirement home if I ever get there.


Still unpacking and nothing connected here - looks like we are off to Kota Kinabula Sabah E Malaysia in a few weeks to do some teaching and refurb our HF station there and will take LF, callsign will be 9M6/G(M)4DMA per my 2002 operation -then we are returning to Ghana in what looks like September to reopen/move the station there too, and Aris Namibia in the Spring as V51/G4DMA to move the HF station there to a new QTH, so a few more opportunities between work and play to listen/xband perhaps.

-may set up the rx in the car and do an overnighter session before it gets into Spring and I lose Eu.

Laurence KL1X in 5



From: [email protected] (Warren K2ORS/WD2XGJ)
Reply-To: [email protected]
To: [email protected]
Subject: Re: LF: Re: Keeping the smoke in
Date: Fri, 03 Feb 2006 01:53:40 +0000

Hi Laurence,

I've thought about leaving the box open but I couldn't do that if there was precipitation of any kind. Also might be hazardous to the neighbor's kids - I haven't seen anyone get near it but it's a big chance to take.


--
73 Warren K2ORS/WD2XGJ
FN42hi
http://www.w4dex.com/wd2xgj.htm

 -------------- Original message ----------------------
From: "Laurence KL1X" <[email protected]>
> No cooling fan Warren just open "ish" air circulation without it things > got a little warm especially at 100F ambient in the summer....I love Okie...
>
>
> >From: [email protected] (Warren K2ORS/WD2XGJ)
> >Reply-To: [email protected]
> >To: [email protected]
> >Subject: Re: LF: Re: Keeping the smoke in
> >Date: Thu, 02 Feb 2006 23:10:18 +0000
> >
> >Hi Mike,
> >
> > I don't think that the cores were damaged from the last incident. I was
> >able to run the 250 watt transmitter through it with no problem and no
> >measureable reflected power. I understand that Laurence also used 3 stacked > >FT-290-77s but actively cooled it. A cooling fan is not easy to do in my
> >case since the tuner is in a weathertight box.
> >
> >--
> >73




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