At long last the NEW ParAclips are on the boom at G6HKS, Richard converts his 2M-NEXTGEN9 and works UA3ARC in KO85 on SSB QRB 2525KM!
You've arrived at the HOME of www.powabeamantennas.com the ultimate YAGI KIT!
PowAbeam Antennas were first sold in the UK back in 1995, the first commercial 'Direct Feed' yagi!
If you're on a tight budget BIG COST SAVINGS are possible compared to ready made antennas with our NEW kits...Check out our BLOG for the latest news...
Richard Mason G6HKS and Derek Hilleard G4CQM welcome you to PowAbeam Antennas DIY/HOMEBREW yagi kits.
ALL the antennas have been carefully designed with powerful YO-Pro 7.23 (G4CQM is probably one of the only Hams to have this professional version) and AO 6.59 from Brian Beezley K6STI and in our opinion there is still NO software that can beat YO for yagi optimisation! Years ahead of its time it's more than capable of meeting the very latest demands when used by a skilled operator and we double check with 4nec2 by Arie Voors! As a result we present both HIGH Q and LOW Q (Q factor) or somewhere in between kits. Our yagis ARE designed with the serious DX'er in mind!!
We can supply FULL kits OR only the parts you actually need and State-of-the-Art designs enabling YOU to produce a high performance yagi beam antenna THAT JUST WORKS! Some of you may prefer to source your own boom stock, perhaps you live in a windy location and want a more sturdy boom, we can help.
Making the antennas is simple BUT you need some basic construction skills and should view this as a learning project with a high performance yagi as the end result.
NEXTGEN yagis focus on F/R (Front to Rear power ratio, 90-270 degrees) particularly in the H-Plane, ignored by earlier designers! If you live in an urban environment this can help reduce noise/interference problems. But remember there is NO SUBSTITUTE for getting YOUR yagi up high and in the clear! Below are two images enabling direct comparison of the TOTAL FIELD of an old design with the new NEXTGEN, you can see the improvement in the vertical pattern!
NEXTGEN yagis have reached a higher level of design accuracy and ALL the popular NEXTGEN designs have been scrutinized by the master himself, Lionel H. Edwards VE7BQH. G4CQM's NEXTGEN yagis really are top end performers, see Lionel's latest G/T table...VE7BQH Charts.xls
NOTES:
* Bracing strut provided - you provide the cord/string
** This is a major construction project - boomless kit only!
'Q' Wet weather performance improves with medium to low Q antennas, see
YU1AW - Yagi Antenna Design Sensitivity in Practice.
However, under normal conditions high Q antennas will deliver maximum performance, the choice IS YOURS!!
Only PowAbeam Antennas employ a 'Coaxial Dipole' driven element. Advantages include; wide bandwidth, highly efficient, low noise and unrivalled simplicity! It also prevents static electricity charges building up on the inner conductor of your feeder cable, when tested it presents a DC short circuit!
Q. Why is there no matching?
A. All PowAbeam Antennas have been carefully designed using YO-Pro 7.23 and AO 6.59 from K6STI to present a natural 50-Ohms impedance at the feed point and double checked with 4nec2 by Arie Voors!
Q. Isn't this so called 'Coaxial Dipole' just another form of folded dipole?
A. NO! RF currents flow around the entire loop of a folded dipole or LFA loop. There is NO current flow at the centre of the inner conductor inside the coaxial dipole!
Q. Do I need to use a balun?
A. NO! The coaxial dipole is essentially formed from two 1/4 wave shorted end stubs. By connecting the inner conductors together at its centre and creating one complete length of inner conductor, forces the outer conductors of the dipole (the radiating elements) into being equal, i.e. having the current node at the dipoles centre and equal voltage nodes at its tips as with any split dipole fed from a balanced source!
Q. Is this coaxial dipole perfect?
A. NO! When tested on an antenna test range calibrated to traceable national standards a slight squint was observed in the polar pattern. In reality the squint is so small that most operators don't even notice even working EME!
Q. Why use a coaxial dipole then?
A. There are NO MESSY COILS OF COAX, NO EXTERNAL STUBS, NO UNPROTECTED CONNECTIONS, NOTHING TO BURN OUT AND NO TUNING REQUIRED...IT ALSO OFFERS GREATER BANDWIDTH THAN FOLDED DIPOLES OR LOOPS FED PROPERLY WITH BALUNS...It is unrivalled in its simplicity and when used in a 50-Ohms direct feed yagi it produces a highly efficient and low noise solution, ideal for weak signal communication!!
REAL WORLD TEST - ONE OF MY COAXIAL DIPOLES USED IN COMMERCIAL APPLICATION - NOTE THE HUGE BANDWIDTH - CENTRE FREQUENCY 152.9MHZ - VSWR BETTER THAN 1.5:1 OVER 15MHZ SPREAD
G4CQM's PowAbeam Antennas yagi designs are highly ranked in the famous VE7BQH YAGI PERFORMANCE TABLES, see the latest analysis NOW in .xls file format! VE7BQH Charts.xls
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ALL of our mouldings are manufactured here in the UK! British Made For Quality (BMFQ)
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