improve FM radio reception--aftermarket HU

[canadave]

So, I'm still enjoying my Eonon GE01 head unit. The one thing that bugs me--the FM reception is a fair bit worse than it was with the stock unit (which itself was merely average, going by my other car's FM reception). I had to use an FM antenna adapter cable between the Eonon and the Vibe's FM antenna wire.

So my question is, is there any way to improve the FM reception? I don't know...maybe twist a bare wire around something a bunch of times? Buy some kind of third-party superduper FM antenna? I really know next to nothing about FM radio and electronics. Before anyone asks, yes I have checked to make sure the antenna is firmly seated in the socket

[ctgottapee]

FM reception relates to the tuners sensitivity, some manufacturers publish specs, and sometimes they are honest.....
and to the size and primarily the height of the antenna; higher the better.
The standard old school vertical antenna is about the best solution for a moving object for the FM band; a large yagi tuned for the FM band around VHFch6-7 pointed towards your station of choice is ideal but keeping it from getting ripped off your car or making a hell of a noise is near impossible (yagi is the arrow looking antennas you see mounted on homes)
The Vibes roof top is the ideal place on a car.

There are some gotchas, like bad grounding, noisy electrical system, a crummy powered antenna (generally powered antennas don't do much, they can only amplify what they receive, not improve reception), living in a crummy reception area, weather, etc. The internet will help you on checking some of these issues.

It's likely they are using some cheap circuitry in that head unit, although many makers now cut costs there.
A few units offer dual antenna inputs, and some car oems use a scheme with antennas hidden in the front and rear glass to get around using a real antenna so the stock radio will have dual inputs. Cadillac did this a lot with their market base wanting to actually listen to the radio, but not see the antenna.

A major manufacturer head unit (not a model sold only in cut rate stores like walmart), with published sensitivity specs, and a old school tall wire antenna are you best hope if you really want AM/FM.

[ColonelPanic]

Barring a not-great tuner, one thing to look at is whether you connected the power antenna lead on the harness that plugs into the car. These cars have an antenna amplifier to work around use of the shorter antenna. If your aftermarket radio isn't sending power to the proper pin on the factory harness, reception will be reduced as the amplifier will not be on.

Does this thing have an AM tuner? Usually AM reception is nonexistent if the antenna amplifier is not powered up.

I don't recall if you have moon & tunes. The audio amp and antenna amp use the same pin on the car harness so if that's not connected you wouldn't be complaining about lack of reception as you wouldn't know your tuner sucks as there would be no sound at all.

[canadave]

Barring a not-great tuner, one thing to look at is whether you connected the power antenna lead on the harness that plugs into the car. These cars have an antenna amplifier to work around use of the shorter antenna. If your aftermarket radio isn't sending power to the proper pin on the factory harness, reception will be reduced as the amplifier will not be on.

Does this thing have an AM tuner? Usually AM reception is nonexistent if the antenna amplifier is not powered up.

I don't recall if you have moon & tunes. The audio amp and antenna amp use the same pin on the car harness so if that's not connected you wouldn't be complaining about lack of reception as you wouldn't know your tuner sucks as there would be no sound at all.

Hmmmm. I could've sworn when I hooked everything up there was a wire labelled "POW ANT" and I connected it. I'll have to double-check, but as far as I can recall, I don't get AM reception at all now and I did before.

No moon and tunes on my Vibe.

[canadave]

You know what....I did some more reading on this online, and now that I look back on it, I think there was a blue "POW ANT" wire coming out of my head unit, that never got hooked up to anything; and, a blue/white wire coming out of the factory harness that never got hooked up to anything (must have been labelled something else). In looking at the penultimate post in this thread (viewtopic.php?t=16757), it looks from the photo that splicing that blue/white harness wire into the red ACC wire next to it will fix the problem.

I'm not entirely sure how to splice three wires together like that (the red wire coming from the head unit, the red wire coming from the harness, and the blue/white wire coming from the harness), but I'm sure I can find out.

[ColonelPanic]

If you have the power antenna lead coming out of your radio's harness, you could just use that.

If you choose an alternate to draw power from, verify it is switched with the ignition and not a constant 12V as you don't want or need this thing on all the time.

[canadave]

If you have the power antenna lead coming out of your radio's harness, you could just use that.

I don't know which wires are which on the harness, though--I stupidly threw out the bag it came in, which had a list of which coloured wires correspond with which functions.

[GOF]

Do you know the manufacturer? Check their website for the diagram.

[canadave]

I don't, unfortunately Again, stupid of me. I ordered it from ebay. I suppose I could contact the seller and ask...

[ColonelPanic]

Is this it? There is a manual there with a pinout of the connector at the beginning.

[canadave]

The link's not working for me, but that's the link to the page for the Eonon GE01, right? If so, yes, I've seen that page many times. The antenna power lead from the head unit is "A3" on their ISO port connector; I think it's the blue one if I recall correctly. What I don't know is which wire it is coming out of the harness on the other side, and that's what I need to know...correct?

I'm going to pull the unit out sometime before the end of the week and have a look. I could swear I tied off a blue/white wire on the harness that didn't seem to go anywhere, but I could easily be mistaken.

Sorry, it's really late here (getting ready for bed) and I may just be missing something obvious with what needs to be hooked up to what.

[Baltovibe]

Barring a not-great tuner, one thing to look at is whether you connected the power antenna lead on the harness that plugs into the car. These cars have an antenna amplifier to work around use of the shorter antenna. If your aftermarket radio isn't sending power to the proper pin on the factory harness, reception will be reduced as the amplifier will not be on.

Does this thing have an AM tuner? Usually AM reception is nonexistent if the antenna amplifier is not powered up.

James, thank you so much for your post!

I had purchased and installed an aftermarket radio in my Vibe in March. Although FM reception seemed OK, it was the AM reception that totally sucked. Thinking I had a defective radio, I was about to replace it.

While installing the wiring, I noticed the typical blue/white wire was labeled "System Remote Control" on the radio harness, and the instructions called it a power antenna. Thinking that the power antenna meant those motorized retractable antennas that the Vibe didn't have, I didn't hook up that wire.

Now, after hooking up that wire this morning, AM reception is much better.

BTW, I used the Metra 70-2003 harness, and the blue/white wire connects to the standard non-moons Vibe radio harness terminal B3, a black wire.

Thanks again, James!

[ColonelPanic]

You're most certainly welcome! Glad that took care of it.

[GOF]

Is there a diagram that shows what wire on the factory harness to power up with the power antenna wire?

[Baltovibe]

Is there a diagram that shows what wire on the factory harness to power up with the power antenna wire?

[GOF]

Thank you.

[canadave]

I finally got around to trying to tackle this. I pulled the Eonon GE01 radio, and I see that there is a blue/black wire that I never hooked up, labelled "POW-AMP", that the manual describes as "Power amplifier control". There is another blue/black wire (same colour, right next to it) that I never hooked up, and the manual describes it as "Auto antenna power". The two wires are spliced together--they come out of the radio as one wire, but then are split so that they are separate wires to be used separately.

On the Metra harness for the Vibe, I have only two unused wires. One is blue/white, the other is orange/white. There is only one black wire coming out of the harness, and it is the GND wire, hooked up to the GND wire coming out of the Eonon radio.

So...do I hook up just the "auto antenna power" wire, or the "power amplifier control" wire, or both? What wire on the harness do I hook the wire(s) up to, I wonder? The blue/white wire coming out of the harness?

[kumquat]

I finally got around to trying to tackle this. I pulled the Eonon GE01 radio, and I see that there is a blue/black wire that I never hooked up, labelled "POW-AMP", that the manual describes as "Power amplifier control". There is another blue/black wire (same colour, right next to it) that I never hooked up, and the manual describes it as "Auto antenna power". The two wires are spliced together--they come out of the radio as one wire, but then are split so that they are separate wires to be used separately.

On the Metra harness for the Vibe, I have only two unused wires. One is blue/white, the other is orange/white. There is only one black wire coming out of the harness, and it is the GND wire, hooked up to the GND wire coming out of the Eonon radio.

So...do I hook up just the "auto antenna power" wire, or the "power amplifier control" wire, or both? What wire on the harness do I hook the wire(s) up to, I wonder? The blue/white wire coming out of the harness?

If you hook up to the auto antenna power wire, the antenna booster will only be activated when you're listening to the radio. If you use the power amp control, the booster will be active whenever the stereo is on. Doesn't really matter, but I'd use the auto antenna power wire.

[canadave]

OK, thanks. So just to be absolutely clear, so I don't burn up my car or my radio:

I take the "auto antenna power" blue/black wire on my Eonon, and connect it to the blue/white "Antenna Amplifier Supply Voltage" wire on my wiring harness. And that Eonon "auto antenna power" does not mean that it has anything to do with antennas on certain cars that automatically raise/lower, right? It's specifically for switching power to the FM radio?

[canadave]

Wait a second...this makes no sense. How would it make a difference in terms of which of the two wires coming out of the Eonon I hook the blue/white wire from the wiring harness up to? The two Eonon wires are both spliced into the same wire going into the Eonon. So no matter which one I connect the wiring harness to, I will still be making the same connection--from the blue-white wiring harness wire to the Eonon.

So I'm not sure what difference it makes. I'm so confused!

[kumquat]

Wait a second...this makes no sense. How would it make a difference in terms of which of the two wires coming out of the Eonon I hook the blue/white wire from the wiring harness up to? The two Eonon wires are both spliced into the same wire going into the Eonon. So no matter which one I connect the wiring harness to, I will still be making the same connection--from the blue-white wiring harness wire to the Eonon.

So I'm not sure what difference it makes. I'm so confused!

I'm not 100% sure what's going on with your wiring harness, but you want the power antenna wire coming out of the back of the radio to connect up to the black B3 "Antenna Amplifier Supply" wire on the factory wiring.

The antenna power output on radios can indeed power motorized antennas, or antenna amplifiers. It's just a +12v output that's active when the radio is on.

When you say the Eonon has "one wire" that splits into the antenna or amplifier wire, you mean it's one piece of copper, not two insulated wires glued together? Either way, it doesn't really matter: the "POW-AMP" is also just a +12v that's energized when the stereo is on. It's used as a signal to an external amp that it should be powered up. It sounds like Eonon maybe just cheaped out and doesn't have a dedicated antenna power that turns off when the radio is off. There's nothing wrong with keeping the antenna amp powered up when listening to a CD or Bluetooth, though, so it's not a big deal.

[canadave]

That's the thing. There's no BLACK wire coming out of B3 position on the third-party wiring harness. It's a blue wire with white stripe.

As for the Eonon--there's a blue wire that comes from it, which "splits" (appears to be spliced, covered by a heat shrink) into two wires, both of which are coloured blue with black stripe. One wire is labeled "POW-AMP" and is described in the manual as being the "power amplifier control". The other wire is unlabeled, but the manual says it's the "auto antenna power" wire.

So which is the "power antenna wire" that you're saying I should connect out the back of the radio?

[kumquat]

That's the thing. There's no BLACK wire coming out of B3 position on the third-party wiring harness. It's a blue wire with white stripe.

As for the Eonon--there's a blue wire that comes from it, which "splits" (appears to be spliced, covered by a heat shrink) into two wires, both of which are coloured blue with black stripe. One wire is labeled "POW-AMP" and is described in the manual as being the "power amplifier control". The other wire is unlabeled, but the manual says it's the "auto antenna power" wire.

So which is the "power antenna wire" that you're saying I should connect out the back of the radio?

The Power Antenna wire from the stereo needs to connect to the black wire going into B3. It doesn't matter how they connect, and it doesn't matter what color the wires in between are. What matters is that the +12V signal getting out the radio on the power antenna wire makes it to the black wire on the other side of B3.

[canadave]

Right...what I'm getting at is, it doesn't appear to matter which wire I connect the B3 wire to. Whether I connect the B3 wiring harness wire to the "POW-AMP" wire, or the power antenna wire, those two both wind up being "the same wire" once it enters the Eonon, since they are spliced together (the two wires merge together before they enter the Eonon radio). So I guess it doesn't matter which one I solder to the B3 wire?

The reason I ask is because the POW-AMP wire is much longer--I had snipped the other wire thinking that I wasn't going to need it. So it would be easier for me to just use the POW-AMP wire to solder to the B3 wiring harness wire.

[kumquat]

Right...what I'm getting at is, it doesn't appear to matter which wire I connect the B3 wire to. Whether I connect the B3 wiring harness wire to the "POW-AMP" wire, or the power antenna wire, those two both wind up being "the same wire" once it enters the Eonon, since they are spliced together (the two wires merge together before they enter the Eonon radio). So I guess it doesn't matter which one I solder to the B3 wire?

The reason I ask is because the POW-AMP wire is much longer--I had snipped the other wire thinking that I wasn't going to need it. So it would be easier for me to just use the POW-AMP wire to solder to the B3 wiring harness wire.

Copper is copper. Your knowledge of electricity indicates to me that this is an install you should not be undertaking yourself.

[canadave]

Well, I don't think I'm *that* bad. I soldered the POW-AMP wire to the wiring harness's B3 wire, and it works.

Thank you for your help.

[kumquat]

Well, I don't think I'm *that* bad. I soldered the POW-AMP wire to the wiring harness's B3 wire, and it works.

Thank you for your help.

Just please make sure connections are solid, particularly the main ground, and all bare copper is fully insulated. Marginal connections have a way of heating up and starting fires, as do wires that have simply been cut and unused without being taped closed.

[jeffypieguy]

Thanks to this thread, I just fixed my am reception problem. The stupid aftermarket harness which was used before I bought the car doesn't have the blue-white B3 connector in it. Whoever installed it just ignored that wire coming from the radio. So I added a lenth of wire to it, stripped it nice and long, threaded it through the B3 hole in the OEM end and pushed the connector over it to hold it tight. Works great. I am planning on getting a better deck with BT and speakers shortly so at that time I'll track down a proper harness that actually makes use of the B3 blue-/white wire and then get rid O my hackjob :p

Thanks for the help though y'all