Hi,
I have a Seat Toledo 01 that initially had a Aura head unit installed. More than a year ago i replaced it with a JVC KD-AXV2 with good performance. As i am not using the radio that much and i live in a big city it took me a long time to realize that the reception with the JVC sucks.
I am not sure if that is the case since i replaced the head unit or something happened to the antenna afterwards but i started to investigate it.
I don't like to put back the Aura to be able to compare it to the JVC but in a specific long tunnel here in Athens when i drive an Opel Astra 08 with the factory radio i am loosing the signal of a specific station for much less time than when i pass with my Toledo and the JVC.
Visually the roof antenna looks ok but there is a crack in the base gasket of the antenna.
I am not sure if my antenna is amplified so i installed a product similar to the ones mentioned in the previous posts with no change at all.
Here i have to differentiate my opinion as i believe that these adaptors are NOT boosters/amplifiers but they are used to ingest dc power to the amplifier that is inside the antenna, IF the antenna has amplifier.
An other possibility in case of an amplified antenna is to provide power to it with a separate cable directly to the base of the antenna under the roof like that:
http://www.eurosportacc.com/images/antennadiag.gif
I didn't remove the roof headliner yet so i have no idea if my antenna has a separate supply cable so if there is no extra cable there probably is not amplified.
So as the antenna power over the antenna cable didn't fix my
problem it could be that my internal antenna amplifier (if any) is broken like:
http://pics.tdiclub.com/data/500/medium/SA550552.JPG
As for the "antenna boosters" inside the head unit i don't think that such a think is valid as the best practice is to amplify the signal as soon as possible and that is just at the antenna and not after a few meter of cable and the losses and noise that in causes to the weak signal.
A quick look at the specifications that i found reveals that the radio tuner part of the head unit have a RX sensitivity of about 1.0 μV for the JVC and the Aura stop at scanning at signal of more than 8μV -that is the only relevant info that i found for the Aura on the internet as i couldn't find the user manual with detailed specifications.
My opinion is that the JVC and probably most of the aftermarket head units have better or similar receive sensitivity so they should have similar performance. In case of great variations i believe that we just have to check for hardware fault or just to verify that the antenna amplifier -if exists- is supplied by using the proper adaptor.
Stefanos
Aura
Signal mit E´ = 8μV (18dBmV) anlegen. DX aktivieren.
JVC
[FM Tuner]
Usable Sensitivity: 11.3 dBf (1.0 μV/75 Ω)
50 dB Quieting Sensitivity:
16.3 dBf (1.8 μV/75 Ω)