A Simple 7 Bands Small Space HF Antenna

[@_0815_]

I don't want to criticize, but this setup seems a bit of an overkill. You could achieve the same with your RT100 and the 891. If you put a 4mm banana plug on the antenna wire and plug it directly into the SO239 of the antenna input and connect the radial network to the earth connection of the little LDG tuner you wont need a control cable. I did just that but without the radial network, I just put the tuner to the rooftop of the car (as seen on your videos) and connected a Diamond MAT-50 magnet mat via a ring terminal over the SO239 of the radio input and fixed it in place with the coax. About 10m of wire gave me 10 to 40m with really good SWR on all bands and no coax loss, no radials but the capacitive coupling between the magnet mat and the car body. Maybe an idea for another day... 😉

[@timg5tm941]

Yep some good points. However, the RT100 is typical of many auto tuners in that it’s impedance range stretches up to around 800 ohms. The MAT 40 is about double that. Now, taking my 9m wire into consideration, let’s look at 14 MHz, the wire is getting close to a 1/2 wave. Already the feedpoint impedance will be in 4 figures. I’m unsure that the RT100 would cope if asked to be a feedpoint tuner. Same on 10m as a near full wave. Thanks for the comments, great to see the interaction. 73

[@_0815_]

@@timg5tm941 thank you for your kind words. I did not really measure the the wire exactly, not even talking about considering the velocity factor, but I had absolutely no problems with the RT100. I think this setup is a prime example where the concept of a "random" wire length comes into play. As long as you hit no super high impedance you'll be fine. A 4:1 in front of the antenna port would also sort this out but that's not really in line with a more streamlined setup. I often use the chinese 5.6m whip antenna on a mag mount, fully extended and matched with the RT 100 as my go to POTA setup for 20 to 10m. I was really surprised that the RT 100 gives a perfect match everywhere on the 10m Band, since it's nearly a half wave length. It really works exceptionally well and got me from southern Germany to the US, South America, Korea Vietnam etc. But anyway, great work from your side as usual. I really dig this kind of practical, out in the field types of videos. By the way, I already told you once over the air, you're making me poor because you made me buy the 891 and the RT100, but I am absolutely grateful for it 😅

[@timg5tm941]

@@_0815_ I’m glad it worked for you. The RT100 and 891 are a great combination using the ATAS mode. Keep on rocking! 73

[@benjaminon5bgo636]

Hi Tim, great video as always. Could you tell me how many radials did you install and how long is it ? All the same length ? Thx 73, Ben

[@timg5tm941]

Hi Ben , thank you. From memory around 16 x 2.5m radials in four bunches of four radials.

[@darrinpearce9780]

Yet another excellent idea to try out on my next portable op. Thanks again for posting great content. 73's from VK land.

[@timg5tm941]

Thanks Darrin!

[@williammclean3870]

I'm currently experimenting using the curly aluminium plant supports from Aldi to make a 2 metre antenna. Ham radio keeps us thinking outside the box.

[@MikeN2MAK]

40m is a great band for POTA over here in the northeast of the U.S. where there is a good population and ham density. The 29' random wire is definitely a sweet spot for portable too.

[@timg5tm941]

Absolutely!

[@Drpepper99uk]

Roger,roger,roger,roger,ROGER!!!😁😉 Great video as always Tim 👍🏻😊

[@timg5tm941]

Thanks!

[@Steve_Wardley_G6JEF]

Hi Tim, I was receiving you up in Bridlington on the Yorkshire coast at this time, you were 5/5 with me but I couldn't get back to you as by portable battery was flat. Perhaps another day.

[@timg5tm941]

Fingers crossed Steve

[@davidlucas6837]

Glad you are enjoying POTA Tim! G8XDD

[@timg5tm941]

Thanks Dave!

[@johnnorth9355]

What time of the day was that Tim ? I fired up the radio between 4.00pm and 6.00pm but got very little on those bands other than noise and some German rag chews on 40. 73. M7BLC

[@timg5tm941]

Last Friday around 2:30-4pm UK time

[@joekrepps]

How many watts? I’m 74/100 towards Mobile DXCC with my 891/ATAS-120A mag mount at 5-50 watts. I ask because it’s becoming a struggle to acquire more countries. I might need to make some changes. Love your videos! Excellent as always!!

[@timg5tm941]

Thanks Joe! 100 watts here

[@izzetmuroz]

Selamün Aleyküm Londra'dan Saygılar...

[@timg5tm941]

Thanks Izzet!