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HOW TO MAKE a multi-band portable field antenna for NO tuner needed for forthcoming QCX mini #sota #antennalaunching #qcx40 #building #transformer


Stephen Sherer
 

Attached please find two vidios that I found helpful for making a 1/2 wave end fed antenna so an  extra tuner is not required. 

Hope you like it.

https://www.youtube.com/watch?v=s-_LyhdGapM
https://www.youtube.com/watch?v=-qfCQTZSIus
--
KE4LJH
Steve, 
Florida


Michael Greene
 

Steve,
Great information! Nice tips included also. I think I'll give this a go myself.
Michael


Richard
 

SOTAbeams and QRPGuys sells trap kits.  Price varies depending on how much power you want them to handle.

I thought about this, but I went the simple route and did a 20/30/40 linked EFHW.  0dB insertion loss from traps.  It takes me about 30 seconds to change bands.  When you're running QRP, every little fraction of a dB helps.

I may still do a trapped dipole for QRO POTA ops.


ajparent1/KB1GMX
 

Interesting and added effort.

Consider this you have a QCX and battery plus key aaand all the usual
stuff in you pack for a day maybe over night in the field, maybe a mountain.

What does you antenna have to be:

Small, light, and easy to set up minimal coax (or any feedline) needed
and matched the band of the radio.  And if all of the antenna, matching
unit, coax and some cord to hang it fit in an altoids tin that would be handy.

Allison
-------------------------------
Please reply on list so we can share.
No private email, it goes to a bit bucket due address harvesting


Rag LB-Three-RE Stein-Roar
 

I made few portable mini dipole and w3dzz for portable use


Best Regards,
Stein-Roar Brobakken
post@...
LB3RE K3RAG 
Skype: lb3re.rag

16. nov. 2020 kl. 23:52 skrev ajparent1/KB1GMX <kb1gmx@...>:

Interesting and added effort.

Consider this you have a QCX and battery plus key aaand all the usual
stuff in you pack for a day maybe over night in the field, maybe a mountain.

What does you antenna have to be:

Small, light, and easy to set up minimal coax (or any feedline) needed
and matched the band of the radio.  And if all of the antenna, matching
unit, coax and some cord to hang it fit in an altoids tin that would be handy.

Allison
-------------------------------
Please reply on list so we can share.
No private email, it goes to a bit bucket due address harvesting


Jason Pirok
 

I haven't tried them, but these are available and lightweight. The owner is a pretty stand-up guy as well!

https://checkout.tn07.com/

On Mon, Nov 16, 2020 at 6:06 PM Rag LB-Three-RE Stein-Roar <post@...> wrote:
I made few portable mini dipole and w3dzz for portable use


Best Regards,
Stein-Roar Brobakken
LB3RE K3RAG 
Skype: lb3re.rag

16. nov. 2020 kl. 23:52 skrev ajparent1/KB1GMX <kb1gmx@...>:

Interesting and added effort.

Consider this you have a QCX and battery plus key aaand all the usual
stuff in you pack for a day maybe over night in the field, maybe a mountain.

What does you antenna have to be:

Small, light, and easy to set up minimal coax (or any feedline) needed
and matched the band of the radio.  And if all of the antenna, matching
unit, coax and some cord to hang it fit in an altoids tin that would be handy.

Allison
-------------------------------
Please reply on list so we can share.
No private email, it goes to a bit bucket due address harvesting



--
Jason Pirok
W4UNX


Marek SP9TKW
 

Those ultra-mini transformers on BNC connector are very cute, but have one major drawback IMO. Because they are attached directly to the TRX, therefore they are at the ground level when oparating. Although this might improve SWR, it will dramatically reduce your antenna gain. Coupled this with low efficiency of a such small transformer a lot of potential transmited RF is lost.

I am not against EFHW, I love them and I am using one myself during my SOTA activations. My favourite is a short version of EFHW4010 (with 34uH coil). I often set it up on 13.5mtr DX-Wire mast as vertical. Transformer is 1.5mtr off the ground and I have 8mtr of coax lying on the ground.

---------------------------------
73 de Marek SP9TKW


James Daldry W4JED
 

I find that large Dixie cups make for much higher fidelity audio.

Jim W4JED

On 11/16/20 7:00 PM, Jason Pirok wrote:
I haven't tried them, but these are available and lightweight. The owner is a pretty stand-up guy as well!

https://checkout.tn07.com/

On Mon, Nov 16, 2020 at 6:06 PM Rag LB-Three-RE Stein-Roar <post@...> wrote:
I made few portable mini dipole and w3dzz for portable use


Best Regards,
Stein-Roar Brobakken
LB3RE K3RAG 
Skype: lb3re.rag

16. nov. 2020 kl. 23:52 skrev ajparent1/KB1GMX <kb1gmx@...>:

Interesting and added effort.

Consider this you have a QCX and battery plus key aaand all the usual
stuff in you pack for a day maybe over night in the field, maybe a mountain.

What does you antenna have to be:

Small, light, and easy to set up minimal coax (or any feedline) needed
and matched the band of the radio.  And if all of the antenna, matching
unit, coax and some cord to hang it fit in an altoids tin that would be handy.

Allison
-------------------------------
Please reply on list so we can share.
No private email, it goes to a bit bucket due address harvesting


--
Jason Pirok
W4UNX