PowerFLARM Core secondary FLARM antenna

On Thursday, October 2, 2014 5:50:30 PM UTC+2, Bob Caldwell (BC) wrote:
On Wednesday, October 1, 2014 1:43:06 PM UTC-6, wrote:

Some people use a directional yagi antenna on the canopy and a omnidirectional one behind the main gear. This combination seems to work very well with otherwise problematic carbon fuselages.



How is the secondary antenna placed? The one I received is flat but is supposed to be in a vertical attitude. I can't find a place that works in my mostly carbon Ventus. I think the blind spot issue is significant. My main dipole is mounted on the glare shield and I get good performance when the line of sight doesn't go through the carbon fuselage. It is easily noticed while thermalling when an alert disappears and reappears depending on the obstruction.

The planes I have seen with dual antennas have the yagi from Dolba (http://dolba.de/htm/loesung_bd8.html) which is sticked to the canopy and a normal "toothpick" antenna placed vertically outside of the fuselage behind the main gear box. However I don't know which is the primary and which the secondary.

On Wednesday, October 1, 2014 10:07:17 PM UTC-7, Eric Greenwell wrote:

If they made the other 90% pay for it, they'd only have to charge
everyone $5.40 to make the same amount of money. And, no irritated
customers, either. They are probably smart enough to know that, so
perhaps there are other factors, or a higher percentage taking it.


Eric Greenwell - Washington State, USA (change ".netto" to ".us" to


In a bundle like PF Core vs unbundled PF Core Pure you need to look at whether the price elasticities for the features are positively correlated, negatively correlated, or uncorrelated. As you point out it's more subtle than charge $54 vs. $5.40 for a single feature. Part of the idea is to establish the value of the bundle as at least as good a deal as rolling up the individual features, otherwise everyone would buy the minimum configuration plus the individual features they want, which erodes overall revenues. Then you can serve the different market segments at prices they are willing to pay.

On Thursday, October 2, 2014 11:03:16 AM UTC-7, wrote:

Some people use a directional yagi antenna on the canopy and a omnidirectional one behind the main gear. This combination seems to work very well with otherwise problematic carbon fuselages.

I tried a Yagi and other directional/high gain antennas. The goal with this concept is to increase forward range out to 10+ miles with the directional antenna and use the second antenna as a complement for 360-degree closer-in collision avoidance. The directional antenna didn't seem to help nearly as much as getting the standard dipole in a good location right up at the high point under the canopy. Go figure.

Of course antenna design and placement is a bit of a black art. The range results from any flight are also dependent on the antenna arrangements of the other gliders you are flying with. A large number of gliders to generate contacts and consistent flying partners help in gauging your antenna performance. I did most of my testing during long contests where there was some consistency in this regard. Needless to say, my time would have been better spent focusing on the flying part. :-)

9B

On Thursday, October 2, 2014 2:39:05 PM UTC-7, wrote:
On Thursday, October 2, 2014 11:03:16 AM UTC-7, wrote:



Some people use a directional yagi antenna on the canopy and a omnidirectional one behind the main gear. This combination seems to work very well with otherwise problematic carbon fuselages.



I tried a Yagi and other directional/high gain antennas. The goal with this concept is to increase forward range out to 10+ miles with the directional antenna and use the second antenna as a complement for 360-degree closer-in collision avoidance. The directional antenna didn't seem to help nearly as much as getting the standard dipole in a good location right up at the high point under the canopy. Go figure.



Of course antenna design and placement is a bit of a black art. The range results from any flight are also dependent on the antenna arrangements of the other gliders you are flying with. A large number of gliders to generate contacts and consistent flying partners help in gauging your antenna performance. I did most of my testing during long contests where there was some consistency in this regard. Needless to say, my time would have been better spent focusing on the flying part. :-)



9B

Looks like my memory served me right. I found the following in the manual:

RFB: Second FLARM antenna connector
Devices sold prior to Software version 3.00 have pre-installed 'grandfather' licences for the features they were sold with (e.g., devices sold in the US prior to 2013 have IGC, TIS and RFB).

Ramy

RFB -

On Thursday, October 2, 2014 2:39:05 PM UTC-7, wrote:
On Thursday, October 2, 2014 11:03:16 AM UTC-7, wrote:



Some people use a directional yagi antenna on the canopy and a omnidirectional one behind the main gear. This combination seems to work very well with otherwise problematic carbon fuselages.



I tried a Yagi and other directional/high gain antennas. The goal with this concept is to increase forward range out to 10+ miles with the directional antenna and use the second antenna as a complement for 360-degree closer-in collision avoidance. The directional antenna didn't seem to help nearly as much as getting the standard dipole in a good location right up at the high point under the canopy. Go figure.



Of course antenna design and placement is a bit of a black art. The range results from any flight are also dependent on the antenna arrangements of the other gliders you are flying with. A large number of gliders to generate contacts and consistent flying partners help in gauging your antenna performance. I did most of my testing during long contests where there was some consistency in this regard. Needless to say, my time would have been better spent focusing on the flying part. :-)



9B

Using a directional antenna for "Flarm A" is not a good idea as your transmitted position info will mostly be sent with strength in only one direction.. This means that other ship's Flarm will not "see you" well if they are without that transmission lobe.

bumper

On Thursday, October 2, 2014 11:50:30 AM UTC-4, Bob Caldwell (BC) wrote:
On Wednesday, October 1, 2014 1:43:06 PM UTC-6, wrote:

Some people use a directional yagi antenna on the canopy and a omnidirectional one behind the main gear. This combination seems to work very well with otherwise problematic carbon fuselages.



How is the secondary antenna placed? The one I received is flat but is supposed to be in a vertical attitude. I can't find a place that works in my mostly carbon Ventus. I think the blind spot issue is significant. My main dipole is mounted on the glare shield and I get good performance when the line of sight doesn't go through the carbon fuselage. It is easily noticed while thermalling when an alert disappears and reappears depending on the obstruction.

I have a carbon Ventus 2B in France. I have a dipole antenna on the instrument panel cover and a second larger antenna installed projecting about forty five degrees downward from the exterior fuselage on the right,just ahead of the gear doors. I paid professionals to do the mounting of my powerflarm and antennae(as well as the Butterfly vario and sensor box; its great!). This arrangement, I was told, was the best solution for the flarm in the ventus. I must say, it has never failed me. Where I fly in France, the glider traffic is very dense (some days like rush hour traffic) and it has never failed me. BTW, in the glider dense area of the Alps, Flarm is required by law. Tow planes must have it also.

On Friday, October 3, 2014 12:02:53 AM UTC-7, bumper wrote:
On Thursday, October 2, 2014 2:39:05 PM UTC-7, wrote:

On Thursday, October 2, 2014 11:03:16 AM UTC-7, wrote:







Some people use a directional yagi antenna on the canopy and a omnidirectional one behind the main gear. This combination seems to work very well with otherwise problematic carbon fuselages.







I tried a Yagi and other directional/high gain antennas. The goal with this concept is to increase forward range out to 10+ miles with the directional antenna and use the second antenna as a complement for 360-degree closer-in collision avoidance. The directional antenna didn't seem to help nearly as much as getting the standard dipole in a good location right up at the high point under the canopy. Go figure.







Of course antenna design and placement is a bit of a black art. The range results from any flight are also dependent on the antenna arrangements of the other gliders you are flying with. A large number of gliders to generate contacts and consistent flying partners help in gauging your antenna performance. I did most of my testing during long contests where there was some consistency in this regard. Needless to say, my time would have been better spent focusing on the flying part. :-)







9B



Using a directional antenna for "Flarm A" is not a good idea as your transmitted position info will mostly be sent with strength in only one direction. This means that other ship's Flarm will not "see you" well if they are without that transmission lobe.



bumper

Yup - always use the dipole for "A" and place it for best all-around coverage.

Op maandag 29 september 2014 19:41:45 UTC+2 schreef :

'CORE has two separate FLARM radio transceivers FLARM A and FLARM B. FLARM A is used to receive and transmit and must always be connected to an antenna. FLARM B is only used to receive, an optional antenna may be used for better reception performance. Usage of FLARM B requires purchase of the respective feature licence.'
Feature licence? Turns out it's a 44EUR charge http://www.air-avionics.com/support/...rflarm_lic.pdf to enable this feature. My understanding is that this fee is just a software activation; the hardware (antenna and cables) seems to be extra.

I agree that it is ridiculous to charge extra money for the license that activates the second Flarm RF antenna (reception only).
Flarm has primarily been designed to enhance flight safety, so you should not have to pay extra for a second antenna.