Extra antenna cable??

[Blackmm]

When replacing my factory radio in my 8G with an aftermarket model, I noticed that there was an extra cable that looks like a smaller version of the antenna cable attached to it. My install went ok and everything works normally, but i have this extra cable that goes to nothing and was wondering if anyone knew its purpose?

[Blackmm]

Any ideas??

[DryBear]

Extra cable on the head unit? Could be a number of things - what brand/model?

[guynlidia2006]

mine was the same way, i was thinking that maybe it was the am attena, maybe on the stock one am/fm is split

[jpyounis1]

i own a 95 3000gt sl as well as the galant.in my 3000gt, it has 2 antennas. the one on the car (which is gone now) and the one embedded into the window. on that car when installing the aftermarket headunit, the larger antenna connector is the outside antenna and the slightly smaller one is the window. this could be the case for you as well. but ive seen this on a few cars.

my 99 galant only had one normal size one for the back window. do you have a external one?
if you do all you need to do is go to best buy and buy the GM antenna adapter which will make the small one normal size and allow you to use it. i work there we carry it in the car-fi section.

good luck

[fliegendaffe]

i know my G has an extra cable, but it's not an antenna cable, it's a cable that would have gone to a cd changer in the trunk if there was one

[Blackmm]

my 99 galant only had one normal size one for the back window. do you have a external one?
if you do all you need to do is go to best buy and buy the GM antenna adapter which will make the small one normal size and allow you to use it. i work there we carry it in the car-fi section.

good luck

I just have the antenna embedded in the window. It seems kind of odd that the mini cable would be for a CD changer instead of a BUS type connector.

[fliegendaffe]

I just have the antenna embedded in the window. It seems kind of odd that the mini cable would be for a CD changer instead of a BUS type connector.

it was a bus type. i think i had 2 bus and 1 antenna behind my deck

[bronxbombr]

there are 3 antennaes . One is also built into the rear window.

[mitsu_vic]

Our Gs had the antennaes in the window the larger one is fm and the smaller near the bottom is the am

[fliegendaffe]

that doesn't make sense. how would there be 3 antennas and why would there be an antenna for am and fm?

[mitsu_vic]

the owners manual makes reference to the larger antennae as fm and a smaller in the bottom of the window am

[fliegendaffe]

but it should come through 1 cable

[mitsu_vic]

heck I don't know...never taken it apart to know...dont ever plan too

[Fernan]

Hello,

I was wondering the same thing about my 2003 GTZ, it only has the rear window antenna and it has two antenna cables ( I assume if a model also has the whip antenna it would have 3 cables or perhaps even if it doesn't have the rear window antenna it may still have the two cables for it.

I look at the manual and it refers to the rear window antenna as a "Diversity Antenna", I googled the term and found this on wikipedia:

http://en.wikipedia.org/wiki/Antenna_diversity

Basicly if you look at the rear window you have two antennas, the main antenna (larger plug) covers most of the window and the last trace on the bottom of the glass ( the sub-glass antenna ) is a smaller 75 ohm antenna ( I found out that it is 75 ohm by looking at the back of the Infinity head unit ).

For FM the factory head unit will automatically select the antenna that gets better reception, for AM ( since AM doesn't have the multipath problem that the antenna solves ) it simply uses the main antenna.

What this means is that if you use a Y cable to connect both cables or if you only connect the larger one then your loosing the advantages of having a Diversity Antenna, what we really need is a smart adapter that lets all AM signals pass unaffected but for FM it only lets in whichever signal is stronger, it also needs to convert the 75 Ohm resistance of the sub-glass antenna to whatever resistance the regular antenna uses. I will start my research into what's commercially available for this purpose and if I can't find anything reasonable I may make something myself :)

[Fernan]

At first glance there's nothing available other than the Y adapters which disable the Diversity Antenna features ( some of them call that a feature: http://www.abt.com/product/33614/Metra-40NI11.html ).

I guess if you really want to keep the Diversity Antenna support either keep the factory HU or find one that supports it ( I haven't seen any ). Building one may be a time consuming task, first we need an array of bandpass filters ( one for each FM station for each antenna since I don't think we can tell externally to which station the HU is tunned ), each filter followed by a switch and then to a mixer, then we need a digital tunner and microcontroller to repeatedly scan all stations with each antenna, measure the signal-to-noise ratio for each antenna and turn the switches to connect the one with the best signal to the mixer which goes out to the HU, I don't think I need it that bad but if I get the time and find enough resources to make it a resonable task and cost effective then I may still try it.

[duh2150]

pics.

[minesbroken]

Diversity antennas are more common in a Toyota than a Mitsubishi. almost every galant I have ever put a radio in ( hundreds ) has had only one antenna lead. It is possible that some models come with a diversity antenna which would have a separate AM and FM antenna. In this case the AM antenna wire is just like the FM antenna wire but it is smaller. I imagine it would probably be with the higher end factory set ups. Infinity and what not. there is no adapter, just plug the larger one into the aftermarket radio and be done with it. If your AM is not as good with the aftermarket radio that is normal. There are no aftermarket radio's that accept a diversity antenna set up and the factory radio and factory antenna are "tuned" to each other and work really really well together. you will never get the same AM reception as you do with a factory radio on an aftermarket radio. I get perfectly acceptable AM reception with my Kenwood 997 radio but not quite as good as I did with my crappy factory radio. but now I have Sirius, Ipod, usb and bluetooth so I don't care.