Paul's
Weather Satellite and Waffle Page |
|||||||||||||||||||||||
|
ZEBEDY What's Zebedy I hear you ask! well here comes
the Waffle again ;-) for those of you that are familiar with the TV program
"The Magic Roundabout" then perhaps you have already guessed, for
those of you that are not familiar then you don't know what you have missed,
Ten points for those that know the names of all the characters, Please send
answers to tim@buctoo.whe.re.isit The correct spelling as pointed out by
David Taylor is Zebedee, but rather than give my new collapsible QFH biblical
associations I decided to invent a new word for it so Zebedy now means PHQFHCA
(Paul Hayes Quadrifilar Helical Collapsible Aerial, I hope you took all that
in because I will ask questions later ;-) History Some of you may be familiar with my QFH Diy
Guide if so you will already know I am mad (but happy) After years of
experimenting with various Aerials for weather satellite reception I found my
present QFH to perform better than any other I don't think I will be making
any changes to it although I do intend to update my Diy guide soon. May I take this opportunity to thank all of
you budding DIY'ERS for the feedback and encouragement. I have been asked on numerous occasions if I
was planning on making a collapsible version of the QFH, so here it is, I
would like at this point to thank Ruud Jansen for allowing me to reproduce his
drawings showing the coax connections, I did draft some out then noticed what
a good job Ruud had already done. I have now built one working version and made
a extra supporting frame for illustration purposes which eventually will
become my final version, the test I have carried out have been of a practical
nature traveling to various parts of the country and setting up my mobile
system including Zebedy without a preamp then recording the pass on mini disc
later processing on my home computer, (so if anyone's got a laptop going cheap
let me know). Although this illustrated version is
performing ok I will continue to tweak here and there, at the moment it does
appear to be rotationally directional. I will continue with the basic spring design
but change the coax lengths slightly, I am considering removing the coax
completely and using the wire frame as the filars perhaps using a trifilar
balun, I will keep this page updated as I progress! ************************************ Click on Image for full view FIG 1 FIG 1 Just a few of the QFH's I have made and tested.
FIG 2 FIG 2 shows the markII frame with wooden centre support, note also the two 15mm plastic pipe clips and the length of 15mm copper pipe (to the right of Zebedy) this has a 15mm to 22mm reducer which will clip into the Plastic pipe clips, the two 22mm copper pipes laid horizontal on the bench are my existing mobile mast, they will fit into each other giving me a 3 metre mast (note the spike on one end) the short 15mm pipe with reducer will then fit into the 3 metre mast. you may find more suitable ways to fix Zebedy but this works ok. FIG 3 FIG 3 shows Zebedy markI and markII, MarkI is complete with coax, note 3 different centre supports, take your pick! the one laid down horizontal also has a coupling which will allow adjustment for correct twist in loops, the wooden support involves more work and will be slightly heavier, all 3 supports are strong enough to support me whilst I use them as seats (with the cross frames attached! I thought I better add that bit ;-))
FIG 4
FIG 4 Showing Zebedy collapsed with wooden centre support and mast extensions OK here's the other bits you will need! FIG 7 Cross frames and Waste pipe I used 20mm (3/4") staples for fastening the wire frame to the cross pieces, then insulating tape to fasten to coax to the wire frame. The wire frame will only work like a spring if you make both loops from one piece of wire so that you have two ends on completion which are then stapled together on the bottom of the bottom cross frame. Be careful with the wire it can easily catch you in the eye so take all necessary safety precautions and have the swear box handy. Until next time see ya. P.S we are hoping to start a "MOBILE IMAGING CLUB" where we can arrange venues for us all to get together and and have a reet good day out in the sun if we are any good at weather forecasting that is. Best Regards Paul Hayes
|