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Discussion Starter #1
Hi All,

Received today my CT27AA08 aerial ''amplifier'' but I have no idea where to connect the blue wire (+12V) to on the wiring loom.
Pin A5 (AUT ANT.)on the car's harness is not connected.
Only GND, Battery, CAN A, CAN B, BOOSTER DET is connected on the car's harness.

Of course I can tap off a switched 12V and use that but then I'm wondering how did the original radio managed to get the +12V to the amplifier?
 

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Discussion Starter #3
Ok since I didn't know for 100% that my navigation system has a suitable output (due to the high current drawn) I did run a dedicated + wire form the cigarette lighter.
Its working fine, now I have good quality radio.

I was surprised that the current drawn by this adapter is around 40mA.
My guess is that its not a +12V trigger signal for the amplifier build in the antenna housing but it seems to power it continuously.
 

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The original radio just add 12V DC to the antenna-output.. In the amplifier theres a small capacitor in line (series) with the cable going to the antenne to seperate so only radiowaves can pass to/from antenne.

BUT...Whats supplying the original antenna-amplifier now? or have you removed that? I suspect all you really needed was an insertion of the 12V DC to your original antennacable so the original antenna-amplifier could do the job & not act as the damper i imagine you have it mounted as now...With an extra amplifier to try to correct the loss & lacking gain from orig unit?

Hi All,

Received today my CT27AA08 aerial ''amplifier'' but I have no idea where to connect the blue wire (+12V) to on the wiring loom.
Pin A5 (AUT ANT.)on the car's harness is not connected.
Only GND, Battery, CAN A, CAN B, BOOSTER DET is connected on the car's harness.

Of course I can tap off a switched 12V and use that but then I'm wondering how did the original radio managed to get the +12V to the amplifier?
 

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I followed instructions in the 'sticky' to clean aerial internals but found no amplification components at the base of the aerial, just a conventional set up with a single wire running back across the headlining.

I've cleaned and checked connections at the aerial (mounting points) but reception remains poor. There is an aftermarket booster (CT27AA08) installed behind the head unit (2-din) which appears ineffectual. It is possible this has failed or that connections are bad which I will explore next.

Is there anything else which can influence reception which I can check ? (It's a 2.4 JTDM Lusso by the way)

Cheers
 

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I followed instructions in the 'sticky' to clean aerial internals but found no amplification components at the base of the aerial, just a conventional set up with a single wire running back across the headlining.

I've cleaned and checked connections at the aerial (mounting points) but reception remains poor. There is an aftermarket booster (CT27AA08) installed behind the head unit (2-din) which appears ineffectual. It is possible this has failed or that connections are bad which I will explore next.

Is there anything else which can influence reception which I can check ? (It's a 2.4 JTDM Lusso by the way)

Cheers
There should be an original antenna-amplifier installed in the "B-collar"? (not sure if right uk-word...What connect cars top/floor between front/rear door, behind where seatbelt are tophinged :) on LHS-cars it should be on drivers side, not sure about wrongsided cars :biglaugh:

I believe that if you get a standard 12-V insertionthingie & remove aftermarket amp. You should get the best signal.
 

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Discussion Starter #7
The original radio just add 12V DC to the antenna-output.. In the amplifier theres a small capacitor in line (series) with the cable going to the antenne to seperate so only radiowaves can pass to/from antenne.

BUT...Whats supplying the original antenna-amplifier now? or have you removed that? I suspect all you really needed was an insertion of the 12V DC to your original antennacable so the original antenna-amplifier could do the job & not act as the damper i imagine you have it mounted as now...With an extra amplifier to try to correct the loss & lacking gain from orig unit?
The original radio should have this build in, so that's answered.
Indeed the AC signal coming from the antenna is superimposed on the 12V DC due to this CT27AA08 adapter lead and the DC part blocked by a series capacitor for the radio receiver.

I didn't change the original antenna amplifier, also i did not check if its in the antenna base (which I assumed, when searching on the forum for information) or in the B-collar.
Since the power consumption is relative high (40mA) my guess is that it was originally powered by the radio which is also the case now due to the CT27AA08 adapter.
No additional amplifier is needed in my situation due to to any potential loss of the CT27AA08 adapter, I had the radio on today to/from work and it worked perfectly.
 
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