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Tony Rowlands
 
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(Vaughan Henderson) wrote in message . com...
Hi Tony,

I'm 99% sure the antenna is passive, not active. Check the solder
joints where the four helical wire antennae join onto the board at the
bottom. I've had one experience with faulty connections (came loose
due to excessive vibration) here.

If a visual inspection of the antenna otherwise looks OK, check the
coaxial cable, in particular the connector at the antenna end. Has
any water got in here?

Iridium antennas don't have much gain, and any additional losses in
the coax cable and connectors really reduce the receive signal.

Regards
Vaughan Henderson


Vaughan
Thanks for the reply.
I have checked the antenna (at the antenna) with a multimeter and have
55 Ohms resistance form the centre connector to shield. Have also
replaced the coax. There are a number of SMD (resistors i think) with
221 stamped onto them. The 5th component is connected on the ground
plane of the antenna to the centre tap. No markings so don't know what
it is. Whe I first opened the antenna it had a fair amount of water
inside it. Dried it out and lacquered the circuit.
Should the antenna have any connection between the centre tap and
shield? All help is appreciated.
Tony
S/V Ambrosia