Frequently Asked Questions
Will this antenna fit in my garden?
Most of our antennas are 1/2 wave designs so an 80m antenna will be about 40m long, 40m antenna 20m long etc. The exception to this is the 421 triband antenna which has a loading coil that reduces the length to 12m and covers 40m.
Does it have to be installed straight or can I bend it to fit the space I have?
As with all antennas high and in the clear is ideal but for most of us this can be difficult to achieve and we have to make some compromises. Most of the radiation occurs near the centre so aim to get this part as high and in the clear as possible then bend the ends to fit.
The SWR is not as low as expected am I doing something wrong?
Every installation is different, height above ground, proximity to other objects (e.g. house or tree), bends in the wire, horizontal or sloper and even the route the feeder takes can affect the SWR.
On a single band antenna it may be possible to adjust the length to improve things but with multi band ones using an ATU is the best solution.
It is normal for the SWR to be low at the resonant point and increase as you move away from that frequency so an antenna tuned for low SWR at the band centre will have a higher SWR at the band edges.
Why are some of the sizes approximate?
Some of the antennas may need adjusting for low SWR a little on installation which alters the length slightly.
The G5RV feeder has a velocity factor that varies by type and manufacturer so 450Ω and 300Ω will have different length for the same impedance transformation.
I want to get onto all the bands with a small garden can you help?
A very common question from new licensees.
An antenna can be two of these but never all three - BROADBAND - COMPACT - EFFICIENT.
So a broadband compact antenna can never be very efficient and may have disappointing performance. I suggest joining a club to benefit from their combined knowledge and using the internet to find a solution that suits your needs.