windshield without antenna? No problem

[mytrplseven]

I decided that buying a windshield with an antenna was way too expensive. So, after some on-the-fly engineering (and a few beers) I found that attaching a THIN wire to the end of the antenna connector (just behind the battery) would work. So I cut a 6 ft. piece of alarm wire (4 conductor) and attached one wire to the end of the connector and wrapping the remainder around the windshield (up the passenger side and over the top). The reception was great. My plan was to pull the rubber outer trim from the windshield and after stripping the white outer shell and discarding the other three wires then placing the thin wire into the trim channel and replacing the trim.

Notes on creating the wire: Carefully cut through the outer white shell in 1 1/2 inch sections and carefully strip them off the cable. Take care here as the stripper can easily strip the insulation off the individual wires. After you've gotten the individual wire you need, solder one end to the wire that comes off the antenna connector at the base of the windshield and encapsulate the connection with shrink wrap. Replace the small cover and install the remainder of the wire in the windshield channel.

The attached pictures should suffice and I'll answer any questions if needed.

[911tracker85]

excellent. I bought a used windshield for my Bro's 944S and did not ask if it has an antenna. the price was right and have not gone to pick it up yet.

but like you, he did not want to spend the $$ for a new one. so I was considering something like you are doing if needed when the windshield is out.

thanks for the post, gives me some optimism on an alternative.

[v2rocket_aka944]

I did the same thing when I put the turbo nose on my early car (originally fender popup antenna)

I only ran a single wire around the windshield, and grounded the antenna plug to a body bolt behind the dash.

Works great!

[mytrplseven]

That's what I did with the 4 conductor cable; stripped out 3 of the 4 wires and kept the black one for the actual antenna. Thinner the better. Swapped out the rear hatch and changed all the trim and rear spoiler today so now I have a really good rear hatch.

[Bukowski]

What is "4 conductor" wire? Is it copper, or what? Why not use a single strand of wire - do you mean use the tiniest OD wire possible for best results?

[mytrplseven]

When you buy alarm wire, it comes with 4 wires inside the cable. The wires are very thin and one should fit neatly under the outer trim piece when it is installed.

[Bukowski]

Ok I'm not getting anywhere so far. What radio do you have? Is there something that has to be done to get the antenna connection to work?

Me:

'87 944 NA
Alpine CDM head unit.
Antenna is plugged in and makes a big difference. Now get a few stations really well. The radio ignores weak signals - might be one issue.

To test, I tried a really long spoil of copper 18 gauge, balloon wisk wire, mechanic wire shoved in the little receiving piece, no change. Filed the connector, nothing.

Looked behind the glove box, the mysterious box and wires that might be the fabled Fuba powered antenna seems like new.

I mean, I like Celtic Soujourn, but every single time?

[Jfrahm]

Make sure your antenna "booster" amp is powered off the head unit (amp or power antenna connector at the HU) or you will lost most weak stations and pretty much all the AM. The power wire for the amp is with the antenna wire at the HU end.

[Bukowski]

Here is where I am confused the most:

The native wires include an RCA-ish looking plug that must have been going to the original Blaupunkt radio. I plugged this into the only female receptor on the Alpine that it fits, and clearly it does something - akin to how you describe : FM ok, no AM.... There's more little wire bits I'm uncertain of.

Now, there's another "antenna" label in the Alpine manual. It looks like it's in the wire harness connection. I'm not sure about this particular connection... I dont even know where to start besides unplugging it...?!? and even if I did... what can you do?...

[djnolan]

As I remember the antenna bundle is made up of a coax antenna cable and a small black wire. The small black wire is supposed to provide power to the antenna booster up under the dash somewhere. It needs to be hooked up to power of some sort. The best way is to hook it to the power antenna lead from the aftermarket radio. It will be hot when the radio is on and power the antenna booster when the radio is on. And if you have a decent radio you may even get AM.

[djnolan]

A little history on this I found on Pelican: The early cars had a fender mounted antenna. When Porsche went to a windshield antenna in the later cars, they had to add an antenna booster to make up for the smaller antenna to get good reception. I have never seen one as it lives buried in the dash. It is about the size of a pack of cigarettes I have read.

It needs power as described in the previous post. Make sure when you or the PO installed an aftermarket stereos that it wasn't disconnected, otherwise you will get bad reception. Hook it up to the power antenna lead on the aftermarket stereo and it will get power when the radio is on. This made a huge difference in radio reception for me.

As for 777's post about using a Cat5 wire as a replacement antenna, it probably would benefit from the antenna booster.

[plyhammer]

Pic of booster

Antenna booster – Plyhammer's Parts

[Bukowski]

thanks, thanks one and all. delay in posting, but I assure you the work is in progress:

* unplugged the power antenna power wire (I guess - you can understand how googling for this information and finding good results is a challenge).

* found blue and blue-white wires from the stereo wiring harness - they were just sitting there disconnected. if you read about this stuff enough, you figure that blue is for power. That's all I'm worrying about for now.... [reads Alpine manual] - yes "blue" is "power antenna" or "power antenna lead", "Connect this lead to the B+ terminal of your power antenna, if applicable". I note that the "antenna" has a line going to the female RCA-ish connector on the back of the Alpine head, as expected. so never mind anything besides the "blue", plain-blue wire.

... the power antenna wire thin wire (If you do this, you'll know what that means) was plugged into something. Not sure where it goes. Will have to reach further. for now both connectors are disconnected. looks like I need an adequate gauge of power wire - I guess copper, I guess 18 gauge - and a typical spade connector but on the other end, I need some sort of more narrow connector to match the original antenna power wire.

there's other curiosities in there, but focusing on the known knowns for now. This sounds like I'm making a mountain out of a molehill but it ought to at least cover the topic for any poor audio-ignorant soul out there... Will report back.

pics below (not necessarily in order):

[Bukowski]

this didn't make it - can't add pics during an edit? am I missing something?

[dgcantrell]

The blue wire from the stereo is a remote power operation trigger of sorts. It doesn't deliver power to "drive" the remote device. It's just a way to tell the remote device to power on just as a low current circuit would engage a relay to power up a device. This blue wire should be connected to the single black wire that leads to the booster that is connected to the windshield mounted antenna. That little black box is mounted just inside the firewall behind the glove box where the lead passes out to the connection on the windshield itself. When I put an aftermarket stereo in mine many moons ago, I had to connect it to get any decent reception.

[Bukowski]

Before I forget:

It looks like the power is the problem, but just to add more evidence on the pile : I always get astonishingly poor reception from one of those smartphone-FM music player devices.

This site notes the trouble but no details...?:

924/944/968 Stereo FAQ

"When installing an aftermarket radio on a car with an active antenna system, it seems to be a common problem to forget to apply power to the preamplifier. The following are the most common symptoms:

Poor reception on FM - only a few strong stations will appear.
Virtually no reception on AM.
Note that the preamp must be connected to a switched source to avoid running the battery down. Again, this is the 'power antenna' lead in the radio's wiring harness."

[Bukowski]

well, I would love to show more details, but this ought to suffice for someone who digs into this:

long story short, make this thing:



... also I have no idea if this is NASA-grade or if there's any consequence to it : 18 gauge copper wire (the bundled kind... not a single piece), spade connectors from a small box from the FLAPS - one as-is, the other I had to simply file down to fit. when I did this, I discovered the tip is made from metal that is folded over on itself. In between was a yellow tint. No idea what that is. Moving on - crimp it, forget to put shrink tubing on it so I used a huge shrink tube, used about five or six different tools from the bin, and voila - when you plug the ends in as shown - the side with the normal size spade is to the radio wire harness blue-and-nothing-but-blue wire, the other side is the shaved spade to fit into the power antenna power wire (so awkward to describe this for a novice) - ... it is very obvious when you plug it in. The station reception goes from OK to a little better than OK, but when you scan around for stations, it is obvious. AM - well, haven't tried yet. the smartphone radio transmitter unfortunately doesn't work much better... meh, maybe a tad... press one of these buttons... oh neat.... next, I took the same 18 gauge copper wire and ran it from the little connector near the battery all the way up and over and down to the fuse box. This might have helped a little - perhaps 777 can say if the 18 gauge copper bundle wire is a dumb idea or not...

BUT

... that's it. oh also '87 944 NA - looks a bit different. the detached wire goes to one of those stiff black wrapped bundles and curls around somewhere, maybe the remaining Blaupunkt wire harness, ... actually might have that manual somewhere... there's other mess in there but I call it done after a bit of electrical tape on the ends.

FM radio - it is a glorious time to be alive.