hplevyak
12-07-2012, 08:10 PM
Folks,
I'm building a GlaStar and currently working on the ACK Avionics E-04 ELT installation. I would like to install the ELT antenna inside the composite fuselage. The ACK E-04 supplied antenna calls out the need for a ground plane when used on a composite structure and state it has to be 48" in diameter. (Foil tape elements 24" long (six of them). And I just don't have that space.
As an alternative, I'm thinking of putting in a Jim Weir style copper dipole "Double V" antenna. I'd build it using copper foil with one of the V elements having each leg 22.5" long (121.5 MHz), and the other V having leg lengths of 7.3" long (406MHz). I'd place this vertically on the side wall of the tail tunnel.
So my question is....Can I legally do this and still meet the requirements of the TSO and FAR?
The ACK E-04 install instructions do state the following:
"Other antennas may be used provided they meet the minimum VSWR requirements as noted in the specifications section of this manual and meet COSPas/SARSAT approval for use with the model E-04 ELT."
I'd sure appreciate some guidance on this.
Thanks,
Howard (GlaStar builder....deep in wiring and all installing all things electrical)
I'm building a GlaStar and currently working on the ACK Avionics E-04 ELT installation. I would like to install the ELT antenna inside the composite fuselage. The ACK E-04 supplied antenna calls out the need for a ground plane when used on a composite structure and state it has to be 48" in diameter. (Foil tape elements 24" long (six of them). And I just don't have that space.
As an alternative, I'm thinking of putting in a Jim Weir style copper dipole "Double V" antenna. I'd build it using copper foil with one of the V elements having each leg 22.5" long (121.5 MHz), and the other V having leg lengths of 7.3" long (406MHz). I'd place this vertically on the side wall of the tail tunnel.
So my question is....Can I legally do this and still meet the requirements of the TSO and FAR?
The ACK E-04 install instructions do state the following:
"Other antennas may be used provided they meet the minimum VSWR requirements as noted in the specifications section of this manual and meet COSPas/SARSAT approval for use with the model E-04 ELT."
I'd sure appreciate some guidance on this.
Thanks,
Howard (GlaStar builder....deep in wiring and all installing all things electrical)