Power antenna electrics

[sblake01]

Is this the switch? I took mine out when I put a modern power antenna and stereo in my 78 about 8 years ago. I still have it if you need it.

[TomoHawk]

I wouldn't know. I'm just going to bridge the pins to see if the thing will go up & down. A screwdriver should work fine for that.

[EScanlon]

That is the switch. Not sure if that's the correct one for Tomo's car though.

AFAIK, the switch mounted above the right hand knob, that was operated horizontally was on the earlier cars, and the switch mounted to the right of the right hand knob and operated vertically was for the later models. Additionally the earlier switch was a "traditional" switch , i.e. rectangular knob with grooves that you slid to one side or the other, whereas the later ones were rounded a rocker style switch.

Enrique

[beandip]

Tomo you have had this car , how many years ? And just now you found the antenna ? Like 240zx I find this amazing .

[sblake01]

That is the switch. Not sure if that's the correct one for Tomo's car though.......Enrique

It came out of my 78 and his is a 78. He doesn't need it however.

[ZSaint]

This is the only item that does not work on my 2/71 240Z. It worked before I disassembled the car for resto. Now, the antennae does not work. I believe I grounded it properly. I used the next size larger metal screw in the same hole to ensure the screw hole was clean and the connection was tight. The radio just keeps searching with the antennae down. Any ideas?

[EScanlon]

The radio searching says that it isn't getting a signal strong enough to lock onto. That has nothing to do with the operation of the antenna's motor. If you were to pull up on the antenna mast (DON'T) the radio should find a signal and lock onto it. This is as long as the coax cable for the antenna isn't broken, or disconnected at either end.

The antenna's motor NOT operating, is either because you did not connect it to the antenna switch at the radio's faceplate, at the antenna, or you didn't change the in-line fuse behind the radio. Look for a BLUE wire with an in-line fuse back amongst the wires behind the HCP. Check and / or replace the fuse. If the fuse is ok, then check to make sure that the antenna is properly plugged into the wiring.

This of course presumes that this an OEM Antenna and an OEM Radio. As such, remember that the two wires going to the antenna are BOTH for the POSITIVE portion of the electricity. The Negative is provided by the ground at the back as Gunner posted. The switch is just a diverter valve. The motor operates in the direction of current. Reverse the current, the motor operates backward.

If the antenna is NOT an OEM style, i.e One of various Automatic Operations, be aware that it will NOT readily plug into the Z's Harness nor will it operate with the OEM radio without some re-wiring.

Automatic Antenna's nowdays are the full up/ full down variety paired with the radio's on/off status. This requires the antenna to receive continuous power, while sensing the radio's operation via a relay. Radio goes on -- antenna goes up; radio off, down even though the power has been cut off. The OEM antenna differed in that you determined how far up / down the antenna went based on how long you held the switch in the appropriate direction.

If you want the full automatic mode, you must provide continuous power to the antenna, which is somewhat difficult at the back of the car, on the far end of the wiring harness. It's not an easy chore to bring a wire through the labyrinth of turns and holes it must go through to get back there. Yet, it's the only way to hide the wiring. Either that or you run it along the driver's side and bury it under the floor vinyl or worse yet, the transmission tunnel and over (or through) the tool boxes.

To connect the OEM radio to an automatic antenna using the ORIGINAL wiring for the automatic antenna do the following:

To use the OEM Antenna Switch with the Automatic Antenna to simulate the OEM Antenna operation (i.e. User determined Height) the trick is in how you provide power to it.

At the HCP, you'll see 3 wires coming through a connector, a solid Blue wire and two others. The solid Blue is Positive Power coming directly through the fuse box, via the Air Conditioning circuit (This blue wire ALSO provides power to the radio). The other two wires are to send the current to one circuit or the other providing up/down at the motor. You won't be making any changes here, just take note which wire connects to the UP / DOWN terminals of the OEM Switch.

At the antenna, find the connector coming from the cash and select the wire that lowers the antenna. To this wire, connect the Positive power wire for the antenna. At the other connector, connect the BLUE lead (usual color for the on/off detect wire) AND a wire that connects to the Positive power wire.

The operation of the Auto Antenna is such that with continuous power, it's default position is in the DOWN position. When it senses current through its Blue wire, then it's relay reverses it's internal polarity and raises the antenna. When power is no longer sensed through the Blue wire, it defaults to it's normal polarity and the antenna is lowered. (Travel in either direction is usually limited by a gear / cam switch that disconnects power at the full up/ down position.)

The method of wiring that I mentioned, allows you to provide SELECTIVE power to the antenna AND it's current sensor. When you do that, the antenna raises. When you move the switch in the opposite direction, power is fed ONLY to the positive lead and NOT to the Blue, this defaults the antenna to lower itself. Since you are controlling the current at the antenna switch, you have full control of how high / down the antenna works.

Using the OEM wiring with an Automatic Antenna AND a newer style radio: (Note: the antenna switch will not be required)

Connect the Blue (+) wire to one of the two wires going to the antenna, and connect the Blue wire coming from the radio to the other. At the antenna connect the (+) lead to the antenna to the first wire above, and the Blue sensing wire to the other lead. This should help you avoid having to run a bunch of wires back there.

Hope this helps.

Enrique

[ZSaint]

I have not checked to see if the "switch" is connected. I have had the wires out a couple of times. I will check tomorrow. I am in a metal building so I cannot get very good reception on a AM radio. the radio is searching but there is no antennae. I will check it all out tomorrow. Thanks for the specific info on the antennae. It is OEM and has all of the switches, wires and fuses. It worked before I took it apart. I think the switch is not connected at the radio. Good suggestion on checking this out. Thanks!

[imhoppy]

I just checked one last nite.The blue and red wire is the power supply The blue and white is the signal.I have a old manual switch that i cut off to expose the three wires

Solid blue is the hot i spliced the solid blue and the blue and red together then i just touched the two hots the blue and white to send a signal to the antenna.This was done in the car but i suppose you could test one on a bench by hooking up the B/R and the ground to a battery and touch the B/W to the hot.WORKED FOR ME good luck.

[TomoHawk]

E-

So it sounds like you need a singe-throw (SPST) switch that stays in the up or down setting? So either it's up or it's NOT up with the new ones.

[ZSaint]

Took my left side rear panel out and got to the antennae wires. I had carefully hooked up the power wire to ground. How could I have been soooo stupid. Hooked everything up correctly and the antennae works like a champ. I have the old system that you need to power up and power down the antennae.

[TomoHawk]

It really is simple to hook up. I'm just not sure why they have a wire for ground, when the two mounting screws should work just fine. Consistency, I'll bet.