On Sun, 16 Nov 1997 07:11:06 +0800 Steve Ireland <sire@omen.com.au>
writes:
>Dear Carl,
>
>Good to hear from you and thanks for the reflector e-mail and your
>kind
>offer. Hold that 'phone call as I think I have tracked some Slinky's
>down
>over here, but have yet to get to the shop to check them out. It seems
>they
>are stocked by games shops, rather than toy shops, in Australia.
>
>As soon as I have checked them out, I will make a posting of the
>details so
>others over can take advantage. Your idea seems to have taken off in
>a big way.
>
>BTW, how do you connect the little devils and are there any mechanical
>practicalities to watch out for when building the Slinky bev? Any
>information in this line would be much appreciated - and probably by
>others
>on the reflector also.
>
>The Juno e-mail thing is really strange. Every now and again I receive
>e-mail direct from a Juno user...
>
>Kind Regards,
>
>Steve, VK6VZ
Hi Steve, always good to hear from you down there.
I already made that phone call but the person I needed to talk to was
away. One person there thought a company called "Hudsons" was a large
customer.
To connect them up in series I tie the end loops together with some small
#16 tinned wire in 3 places and then go around the complete loop with
solder. Every spot that is soldered is then sprayed with aluminum spray
paint. Others use rust preventative paint and cold galvanizing. Whatever
works is fine.
A few have suggested immersing the individual Slinky's in liquid tool dip
first and then just touching up the joints later. I have no idea how this
will affect the velocity of propagation but it sounds like a cheap
solution for long term protection.
Perhaps if you have the time you can experiment with the terminating
resistor for best F/B and aperiodic performance. Then vary the xfmr
ratios for VSWR match to the feedline. There is still a bit of work
needed to optimize this antenna, although it appears to work fine when
treated as a wire Beverage. I heard you on it !
If you have the space available, adding 3 radials on the ground in front
improved the directivity here. Fan them over a small arc of about 30
degrees. When properly terminated and matched the radials may be
moot....I dont know.
Another idea is to feed them from both ends with identical transformers;
the terminating resistors would be in the shack in the switch box and the
value would be the feedline impedence. This would require the tests
mentioned above to determine true needed values of It works on paper
anyway !
73 Carl KM1H
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