In a msg of , Ivy Iverson writes to Ed Kriston:
II> | |~~~| |~~~| |~~~~|| This is a variation of an idea I read
II> | ______| | | | | || about some time ago - a Ham hid a
ipole
II> | | \ |___| |___| || under his wooden deck, and it worked
II> | |_____ \ || well for him. Only in this case you
II> | | \ ____|| would be using a G5RV instead of a
II> | _____| To xcvr | | plain dipole. You will have to
II> | | |____| experiment, (or do some math), to
II> | |____ 20 X 20 | determine just how big to make the
II> | | attic | zig-zags so that it comes out roughly
s
II> | _____| ___ | I have drawn it here. You might even
II> | | | | | mount it on the underside of the roof.
II> | |________| | |
II> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Ivy this was one of my more bizarre attempts to hide an HF dipole outside.
The idea was use a scrap PL-259 female connector with 70 foot `legs' of wire
from the live (centre pin) and the ground (mounting hole) of the connector.
The 70 feet lengths of wire were tacked in a zig-zag pattern along the
support beams under the deck about 2 to 3 feet off the ground.
Recieve was great on 160 to 20m but when it came to transmit it was a bit of
a bear to get it to tune on 80m where I had orginally intended it to be used.
I eventually did get it to resonate on 3.700 where I wanted it,but when the
deck was covered in snow the tuning went nuts as water dripped down thru the
deck cracks and froze on the wires.
Great for the summer and fall but useless unless the deck had a sheet of
frozen snow on top of it first to `seal' it from dripping water.
Or you had a deck with no gaps in the deck planking.
This same idea can be used in an attic but tack the zig-zag `legs' to the
truss beams in the roof with the PL connector hanging at the centre of the
roof peak.
Centre line of roof
/---\ /---\ | --\ /---\ /---\
| | | | | / | | | | |
| | | | /--- PL--- | | | | |
| | | | | | | | | |
| \--- / | | | | | | |
\---/ \---/ \---/
Wires would be tacked along the roof truss supports with the feed point in
the centre of the roofline in the middle of the attic.
Compacts the dipole into a small space,but the tuning may suffer some from
the folding of the `legs' so may have some fun getting it to tune-up.
--- GoldED 2.42.G1219
---------------
* Origin: VE3SJN....Moderator....HAM_TECH (1:163/506.4)
|