On the last weekend me and João, CT7ABE, made a trapped dipole for 20, 30 and 40m.
We used the pico traps from Sotabeams, which are super easy to to build and tune and very lightweight.
After we have done some testing with the dipole and the MTR-3b.
The RBN show that is working very nicely but we hadn’t more time to use it on real QSOs.
The traps are now ready for a “proper” SOTA test after liquid rubber coating.
This means a SOTA activation, ASAP…
Anyone have SOTA experience with a trapped dipole such as this one and the MTR or the KX-1 ?
Tnx de Pedro, CT1DBS
I’ve had my SOTA beams, trapped dipole for over a year now and have used it with my MTR v2 successfully for lots of activations in GW and for a few activations in Canada last year.
It is my main set up now and works very well. I haven’t bothered to use my kx1 since building the MTR.
Thank you for your thoughts. Does your traps have a waterproof coat ? Does it really matters ?
No, they are not waterproofed in any way Pedro, When I return from an activation I always make sure my radio kit has dried out before putting it away. I don’t think it makes too much difference whether you waterproof the trap or not for the occasional activation, but if I had the liquid rubber coating to hand I would use it.
GL with your new portable set up, I’m sure it will work well for you!
Did the coating change you resonance point or SWR? I have purchased the traps but not built the antenna yet.
TNX Roger. This setup will replace anothe heavy one on my work trips (KX-1 + endfed LW +1:9 balun)
No. If any difference exist in the resonance point is neglectable.
The coating liquid is the indicated by Richard G3CWI from SOTAbeams and it worked exactly as supposed.
I will publish all the stuff about this traped dipole on my blog soon (https://ct1dbs.wordpress.com)
73 de Pedro
Hello Pedro, what is the lengte of the trapped dipole? Rienus
Until now I dindn’t have the time to measure the lenght of each piece of wire between the traps… And I’m away from home, working without the chance of doing SOTA.
Tomorrow evening I will let you know the exact lenghts.
The details of the antenna were published in my blog 20/30/40m trapped dipole | CT1DBS/CU3HF
73 de Pedro
All details are in the blog. If you need furtjer help let me know.
73 de Pedro
I visited your website; very good article and description. I am going to order the components at Sotabeam. 73, Rienus