[HBQRP] Mag loops again - plans - - springtime IS comeing.. right???

[Arnie Grubbs]

Hi Group...

Well, the warm day yesterday (45 deg F   Yay!)  and the forcasts for next week
of highs getting into the 50's!  made my thoughts turn to antenna work.

A number of people in the group have been experimenting with Mag Loops.. and 
I found a guy on the mag loop list that has an interesting QRZ.com page talking about
some of the mag loops he has built.   Log in and look up the call of K4HKX .  
He has some interesting designs on his QRZ page.  

At the last QCWA lunch, I gave Ralph W0SMY a small DC gear motor for him to play around with
for driving a low power mag loop.  I hope to find out how he's been doing with it.
Its a 2 RPM 12 volt motor I found on the web for under $8,  so I got a couple of them 
with the thought of a loop for the higher bands for portable use, such as field day and 
Lark In the Park.  
 
My main  interest in mag loops is for the lower bands for home use.  I have a small city
lot, with poorly placed antenna support options. This is what leads me to look at 
mag loops as one possibility for getting a signal out on 160 meters. It should also be
useful on 80 meters too.. with the added benefit that it should reject a lot of the local
noise level from noisy power lines and other "rotten"  QRM.    My lot is 50 ft
wide by about 150 deep.  With a large (55 ft tall) oak tree about in the middle of
the property, and my 40 ft tilt over pole about 50 ft from the 4 lane street in front of the house.

If things work out, I hope to put a low band loop up this summer.  Probably will have to be
on top of my 8x12 garden/tool shed at the other end of the lot.    Since this is about 75 ft from
the house, I am thinking that a stepper drive is out of the question.  I am thinking of using
a bias "T"  at each end of the coax cable to provide DC voltage out to the loop for a small gear motor.  
Use a PWM circuit to give variable speed to it, using maybe a 555 timer chip and a couple 
of variable resistors to set the high and low speed. 

Darrel K0AWB had mentioned that he might be able to get some more  of the 'scrapped'  larger hardline cable.
 I would like to be able to run 100-200 watts and as the 'borg say, resistance would be futile!  or at least it would make it less efficient.  
I hope he can come up with some more, as I would like to get some.  (Hint Hint.. nudge nudge..)

Our next meeting is 3 weeks away, on March 8th.  This will be the last meeting before OzarkCon 
and the last time to do a practice build of the project for the build-a-thon.   Have we ( HB-QRP group)
gotten the sacrificial kits to do some test builds yet?  If not, are we expecting to get them in time to
do so?   Just was wondering. If we do get them in time,.  I figure if anyone can find a problem (screw something up) in a kit, it would be me!   As N2CQR said in several of his blog's, "Regen receivers are the offspring of the devil"...  so I think it would be wise to have several people do trial builds to get things
sorted out..

I am also signed up for the first build time slot at OzCon. So if you need volunteers to build one, I have my hand raised!

Until next time..
73 -  Arnie KA0NCR