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2m/70cm dualband quad antenna

5m vertical multiband GP antenna

An 80 meter multiturn magnetic loop


HF + 2m SDR Transceiver

SDR Transceiver Version 2

2m - HF transverter

2m transverter for the SDR

Computer controlled Mobira RC25

Mobira MD59 on 70cm

Telcom TE-157 - remove the beep


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Last update 18.2.2008

Multiband 5.2 meter tall GP antenna

Click the image abowe to view a series of pictures related to this project

Update 20.8.2007

Within few weeks I have worked 12 countries on 40 meters and total 44 on HF. Longest QSO is Bhutan, about 6tkm. Even though the antenna is only 12.5 percents of the wavelenght or 50 percents of the quarter wavelenght at 40 meters, it seems to work amazingly well. I have listened stations coming 59 from the States and Japan on several evenings!

Happy happy, hi!

Update 5.8.2007

The GP-antenna is now transformed to a real multiband antenna, including: 10m, 12m, 15, 17m, 20 and 40m bands. SWR readings on all bands less than 1.3:1. QSO test results will be told after some use of the antenna. Look the series of pictures above

Update 21.6.2007

During about 10 evenings I've worked 30 countries at 20 meters.

Update 4.5.2007

With in few days I've worked the following countries on 20 meters: Italy, Malta, Georgia, Bulgaria, Serbia, Russia, Slovenia, Ireland and on specialiyty is Rep. of San Marino - Italy. So, the GP works pretty well :)

BEGINNING: 3.5.2007

I think quite a many radioamateurs have the same common problem: There is no space for an antenna, or you're not allowed to put up one. Well, I have the first problem, there really isn't much space for one. If you are ready for some compromises, this is something that might work for you too.

Basically, we can tune any kind piece of metal to a resonance and any practical wire lenght can be made resonant. My approach was to make a decent 20 meter GP antenna from a fishing rod (wire run outside) and tune it to other bands, including 40m, 17m, 15m and 10m. I didn't want to make the antenna inductive (over a 1/4 wave lenght) on 10m-17m because tuning would have need more complex network, instead of traditional LC lowpass tuning, so I came up with an idea: Why not use an radiator that could be put in half with a switch?

So, a 5.2 meter long radiator would function as a 20m perfect 1/4 wave GP (good radials needed) and cut in halve, 2.6 meter long radiator works as an 1/4 wave 10m perfect GP, WOW, one band added already, just by adding one switch in the system!

To stay on the capacitive reactance, I desided to use the 2.6m radiator for 10m, 15m and 17m and 5.2m radiator for 40m. Using NEC I could figure out proper LC network for tuning the antenna.