We started with some experiments to develop a 80 and 40 meter dual band wire antenna for 200 watt. With a matching network housed

in the same housing as the 40,20 and 10 watt HyEndFed MultiBand

The first tests where great. The overall lenght will be between 22 and 25 meters long with a coil on 20 meter.

So the antenna acts has a full half wave on 40 with great efficiency and a shortend half wave on 80 meter.

No tuner needed for the 40 meter band. On 80 you need a tuner on the bandedges.

After some alignment of the wire length  and carefully experimenting with the  isolation coil in the wire we managed to make a 5
band antenna. Good for 80, 40 ,20 ,15  and 10 meter. On 15 meter some tuning is necessary.

On the left the coil for the 80 &40 meter multiband on the right the coil as used in our 40,20 and 10 meter HyEndFed multiband

We started to develop a muliband HyEndFed for 40, 20 and 10 meters. A lot of people were asking for it.

We designed a new matching network and a loading coil. The antenna will be 12 meters long. No radials. Just a

little matching box with 12 meter wire and a loading coil in it. No tuner needed. Just as the monoband HyEndFeds

with the only difference, the loadin coil.

Here you can see a prototype of the loading coil. The coil is mounted on 10 meters. Watch this section for more info
the next weeks!

This is the principle of working. The coil acts as an line separator between 10,20 en 40 meter.
For 20 en 10 only the portion between the Matchbox en coil is active.
For 20 a half wave and for 10 a full wave. On 40 meter band the total 12 meter is used. The coils compensate the lack
of wire for the half wave working principle.
The Match Box transforms the high impedance to 50 Ohm.

Loading Coil with heat-shrink tubing and stainless steel  bolts and nuts. Still prototype

Matching network. Ringcore with teflon coating,  Cu wire, and condensor. Working prototype but on 10 meters the
torid core heats up.  We are now testing with different core type's  to lower the losses

This is the SWR on 40 meter. The antenna is mounted as a sloper. From the 3th stock down into the garden.The

swr is below the 1:1,5 on the whole 40 meter band.

SWR on 20 meterband. No need for a tuner for the 20 meter band.

Idem SWR on 28.500 MHz. On 29.500 the SWR is 1:2.0. For most rigs the RF amplifier will be starting to reduce pwr.

So there you need the help of a (internal) antenna tuner

This is the location of the measurements. This is a typical location as is by many hams in The Netherlands. A House in the
middle of a row with a backyard of 13 meters. The ladderline has nothing to do with the Multi Band HyEndFed. Its the
ladderline of the G5RV junior.

The maximum power of the antenne will be 100W PEP. We are working on a matchbox for 200/300 W PEP.

This is the final version of the MultiBand HyEndFed antenna.

We found a resource in USA for High Quality  silver plated PL259 chassis connectors with teflon insulation.

From now on we are using these connectors.