The 'E' Type Forum

Existing manual aerial has had an accident, so considering replacement with electric version. Looking at the wiring diagram and wiring in the rear wing, I have WK (white/Pink) and NP (Brown Purple) . These connections are live (12 v) when the radio is switched off, and dead when radio is switched on .Is this correct ?? Wiring diagram shows a relay can be used. Is this essential, and if so which one ?? Any tips/hints, or pictures of an in car installation appreciated . I like the engine sound and rush of the breeze, but "others" like some form of entertainment !!!

Dear Richard,

The radio needs 12v to run and the usual source for this is the white/pink wire. The 12v is switched though the radio's on/off switch and this output (typicvally also white/pink but only live if the radio is on) goes to the boot to power the antenna relay contact. The other side is of the antenna relay winding is grounded.

The brown/purple wire provides power to antenna motor to either move the antenna up or down. This is done by way of a dual pole dual throw relay.

The antenna motor has two windings, with a common middle wire, so is wired Left-Centre OR Centre-Right to run the aerial up and down respectively

This is achieved through the double throw double pole relay. It is wired so that brown/purple goes into one of the centre poles, earth goes to the second centre pole, one normally closed contact joins one normally open contact and the two remaining contacts go to the aerial motor. The aerial motor also has a third wire to earth.

You simply have to wire up the three motor wires such that Left-Centre are connected one way and Centre-Right are connected when the relay is in the oppossite state. If you trace that through, you'll find you either connect 0v-12v to Left-Centre the first way round and 12v-0v to Centre-Right the other way round OR vice versa.

kind regards
Marek

Hi Richard,

I fitted a perfectly normal, modern Electric aerial to my 2+2. SNG Barratt sell one with a motor separate from the aerial, but my modern one fits fine. However, if you already have a hole drilled, you may have problems fitting an all in one unit. There appears to be lots of space, but the spare wheel gets in the way and I had to angle my aerial to lean in toward the centre line of the car. Also if you locate the aerial further out to the side of the car, your aerial will need to have an adaptor capable of fitting to a steep angle of the wing. It of course depends on where your aerial hole is already located.

I did not use a relay, because my aerial has one built in. You do need one really, because the output from the radio is not designed to provide sufficient power to raise the aerial.

First question is, does your radio actually have a control wire for the aerial? Most modern units do, older ones, may not. My unit is a modern design, with an old, twin knob look, USB and Aux (for Ipod or similar) inputs. The radio gets power from a white/pink cable connected to fuse 7. This fuse only receives power when the ignition is on, so the radio and aerial only work with the ignition in ?accessory? or ?on?.

The signal from the radio (normally a blue wire), is connected via another white/pink cable down to the rear RH wing and provides the signal to the relay which you locate there - in my case, this went straight to one of the wires on the aerial (depends on the aerial which one it will be, but the aerial wiring diagram should tell you).

You connect a wire (shown as brown in the wiring diagram), which in the diagram is actually very long but in reality need only be a couple of inches, from the supply side of fuse 4 (i.e. to the side connected to the battery) to an inline fuse (use a cable capable of taking a fair amount of power) and then to the Brown/Purple wire, which comes out just above the radio. This wire goes down to the aerial location as in the case of the white/pink cable already mentioned. It is the power for the aerial, whilst the white pink lead is the ?sense?. What will happen, if you have a radio with an aerial output, is that when the radio is switched on, the white pink supply to the aerial is energised, the relay makes and the brown/purple wire becomes connected through the relay to power the aerial up. Obviously the reverse happens when the radio is switched off.

Photos:

My Aerial



Behind Centre Dash.



Behind Radio.



Installed, with aerial drain routed to outside the car. I replaced the bracket with a better one - this was a trial, and the aerial now leans in a little more than this photo shows - this position fouled the spare wheel.



Hope this helps,

Regards,

Simon.

Thanks for the replies, I'm sorted. Pictures and narrative a great help .Examined the dash board wiring, only variance from Simons description was the wire from the number 4 fuse box was purple ,not brown. Probably opt for the SNG Barratt version with separate motor, Hole already drilled in rear wing. I will see if they supply the relay, but a DPDT automotive relay appears to be widely available.