Here two user reports about the RoomCap antenna:

They speak for themself.

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Betreff:  Bravo -Room Cap Antenna
Datum:     Fri, 20 Oct 2006 18:59:12 -0700 (PDT)
Von:     Paul Ragany VE3UNF <........>
An:     hb9abx.......

Hi Felix :
 
I have built the 20 meter version and it has reached more
than my expectations.
The antenna is fantastic - It is unbelieveable- I have been
comparing it to my G5RV and it out performs the G5RV .

Details:
Most tests were conducted between Tampa (Florida), my
location, and Toronto (Canada), VE3ZUH, over a distance
of 1700 km (1060 miles), using an FT-747 with 75 W output.

After two weeks, the results of my testing with VE3ZUH far
exceeded my expectations . VE3ZUH consistantly reports 
2 s units better on the Roomcap compared to my G5RV. 
I check in to the Maritime Net everyday on 14300.0 and
I consistantly get a strong 5 and 9 report from the net controllers
who are scattered all over the U.S. at various times of the day.
With the G5RV  I get  5 and 8 to 5 and 9 reports.
 
On DX on Oct 19th I talked to OH2BH and OT4A  (Belgium) -
they report 5 and 9 for my signal and I receive them at 5 and 7  .
On Oct 20th  talked to Rob -HA503 FIN -special event station
in Hungary -he reports a 5 and 9 and I receive him at 5 and 7.
The G5RV was hearing 4 and 3to 5.
 
On receive, I average about 2 s units better about 50% of the time.
The signals are the same about 25% of the time and the G5RV
is about 2 s units better the other 25% of the time. I attribute that
to the 180 directionality if the G5RV ( north/south).

Thanks for everything and we'll keep in touch, 73
 
             Paul A Ragany VE3UNF

PS: The G5RV is 2 x 15,8 m about 9m above ground, with
       450 Ohm ladder line and symmetric tuner ATR-15 at SWR 1:1
       The RoomCap has a radiator of 1,5 m length,
       installed on a wooden stand 1,2 m above ground.


UPDATE 28th Oct 2006:
HERE are pictures and more information ( <--- click on HERE to read)  
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Betreff:      RE: hb9abx antenna
Datum:     Sat, 21 Oct 2006 15:52:40 +0200
Von:     jeveraert ON6EJ@.......
An:     hb9abx@.......

Hello Felix,

On my way back from work (Italy) to home (Belgium)
I had some time to visit you in Basel.

I was searching for a good antenna that is small in size.
Thanks to the Internet, I came across your website where
you published some information about your newly designed
RoomCap antenna.

I expected to see a mobile antenna that performed well,
I have seen other portable and mobile antennae, so I have
an idea as to what I might expect.
What I have seen was an antenna that, due to it’s design,
looked a little bit bulky.
This (maybe) disadvantage  ‘’look’’ was quickly forgotten
when we made  the first QSO’s.

As simple as it can be, from the car with the TS50,
several qso’s were made.

No comparison with what I have experienced  before
during other mobile HF operations.
Signal reports obtained were outstanding, even when
using a transmit power power of 10 Watts !

My impression of this antenna is very positive.
I’ve never seen any antenna performing like the one
you have on your car ! (taken into account the size of it)

I’m very glad that I’m now able to build my own.
Thank you  for the good work !

Best Regards

Jan, ON6EJ

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