Re: LF: Re: Keeping the smoke in

["Laurence KL1X" <hellozerohellozero@hotmail.com>]

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: k2ors@comcast.net (Warren K2ORS/WD2XGJ)
> Reply-To: rsgb_lf_group@blacksheep.org
> To: rsgb_lf_group@blacksheep.org
> 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" <hellozerohellozero@hotmail.com>
> > 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: k2ors@comcast.net (Warren K2ORS/WD2XGJ)
> > >Reply-To: rsgb_lf_group@blacksheep.org
> > >To: rsgb_lf_group@blacksheep.org
> > >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