DIY $4 QRP Multiband Endfed ultra simple + lightweight 40/20/10 (30/17/12)

I have build a ultra simple multiband endfed antenna. It weight 58 Gram only.
______________
parts list:

1x FT50-43 ferrite toroid
1x 100pF 1000V capazitor
1x 50cm of 0.25mm enameled copper wire
1x SMA female device connector
1x PVC pipe diameter 28.5mm length 60mm
1x 12m 0.14mm2 insulated wire

Other Material:
-hot glue or epoxy
-solder iron
-tape
-some shrink tubing

[QRP.lifestyle]

PLEASE READ THIS!!!!

I did 3 bifilar primary +7+1+7
This is 18/3=6
6x6= 36
36:1
36x50 Ohm
Is about 1800 Ohm
But anyway this antenna works.
Not good but it works all the bands.
I will do a measurement video soon!
Ham radio, it is what it is-experimenting fail and win.
This time a mistake with a win at the end 😉

73 David DL1DN

[Steve-GMHUU]

Thanks for sharing. Very simple and lightweight. Best of all, it obviously works. If you have an antenna analyser or VNA, it would have been interesting to see what the match looks like across the bands.

[eugene-anthony]

Thank you, everything is very interesting and described in detail!
We are waiting for new interesting videos.

[nickrupp]

Very nice small compact antenna. Thanks for the idea.

[najroe]

Great work, only a minor point, that minor assymetry forced on the winding by the connector schewes the frequency response some (yes even toroids are affected by neatness of winding) and thus the SWR some, just minutely (worst was 0.04 units) but on QRPp it might pay to chase the extra with a 7mm longer unit

[dlman]

Keep your good work ! Prost and 73, DL2MAN

[carsten]

Klasse Antenne David!!! Genial simpel und effektiv! Werde ich mal versuchen nachzubauen. Thanks by the way for the qso on 20 m vorgestern. 73 aus Dalarna in Schweden hope to hear You again soon
SA4GWT

[enigmarbs]

Hi David,
I think you try to build an 1:49 ratio, not an 1:64 ratio.
But the two turns twisted ( in your video 3 turns ) counts also!
So you have to wind 2 turns twisted, 5 additional turns, than 7 turns in the other side.
This would be 1:49 or 2/6+8 turns for 1:64.
But if it works in your case...fine business 😊

[pongo]

Love your pen with the bottle cap. Great video.

[yusup]

Nice sharing. I see a twist wire turn clockwise but when a single wire first turn on 7 turn is backward am I right?

[ronmikkenie]

Everybody noticed the mistake in the UNUN ratio. But running the FT817/818 from the internal battery limits the power to 2.5 Watts, so your TX is even 3 dB down. Which makes the result even better! ;-)

I like the practical part of the video. Most show only the schematic and the end result. Not the struggle to get the wire on the toroid.

And making mistakes is key to evolution. Edison wanted to make a device to speak to hard hearing people and invented the phone...

[johnkiljan]

Interesting. You gave me some ideas for my own portable EFHW plans. Thanks.

[pi]

Perfect timing! My ebay shipment of toroids arrived today!

[reym]

Thank you David. I like the QRP spirit. Keep it light and portable. It works and thats what matters. Im a fan of QRP. 73 from NZ de ZL1REY

[KUL]

Thank you David for sharing! 73, Dave, KU9L

[jaywilson]

Very good video, thanks. Let me be sure I understand, you worked all these bands with no tuner on the FT-817 with low SWR???

[t.n.]

Tolle und leichte Antenne...Danke
Frohe Weihnachten!

[bvds]

Very nice. Thanks for sharing the detailed steps! Well done.

[warplanner]

Just so your viewers are curious, the crossover turn on the transformer is do the ends of the wire are 180° apart. No other magic.

[tomg]

With the way the antenna connection is coming out of the toroid, there is no reason to do the crossover winding. Just wind them all the same direction, and the SMA connector will fit better.