Sorry, HU = Head Unit (radio, Chorus or Concert).Antenna amplifier 8Z0035225 has only co-ax-cable and from the other end to wires blue and black which goes to rear glass---antenna?
Where comes power supply? What is HU?
I was sure antenna amp power is not supplied via the co-ax cable, but, maybe I'm mistaken ...
@RABIn my experience all VW/Audi radios supply 12v to the aerial amp, via the coax. That's why you need one of these:
PC5-52 Signal Separation ISO - ISO for Audi Seat Skoda VW | eBay
This amplified aerial adaptor fits in line with the car's aerial connection and has a built in booster to help increase signal strength. Antenna Adaptors connect your car audio unit to the car's external aerial/antenna.www.ebay.co.uk
when you install an aftermarket radio. I've tried Sony, JVC, Pioneer, Aiwa, and Pure radios and none have a built-in 12v supply for the FM coax (the latter does have a 12v supply for DAB). What they do have though is a switched supply for an aerial which you connect to the adaptor.
RAB
Thanks @Andrew, will read, mark, learn and inwardly digest!Hi @PlasticMac
Good detail of the aerial wiring with the diversity unit and head unit (@sonicci if you have a diversity unit) is given in a few posts by the knowledgable fellow Andrew Sellors, here, well worth reading.
Andy
Edit. Some previous pictures.
View attachment 70776View attachment 70777
The amp gets it's supply via the coax (thanks @RAB), which provides positive (centre core) and negative (screen), so no ground required.Ok I don`´t have diversity unit (should it be near the battery, there are only some kind of balancing weight?) and I also don´t have the second amplifier 8Z0035225B so the coax must come straight from Chorus, I have only one amplifier on the right hand side trim, I think that it is impossible for amplifier to ground from body, it is so well painted? Is something missing?