Quote:
Having just had my empeg installed in my new car, I've got some interest in something like this. A few questions...

1. You mentioned you were having problems with engine noise inducing a false start, is that still the case?
2. If I understand right, it switches over as soon as it senses audio, and then waits for a period of silence before switching back. How variable is this time period between switching back?
3. Is it possible to tell it never to switch back? i.e. always switch when it gets sound, but wait for the user to manually switch back to Aux.
4. Once you have something reasonably finalized, would you consider building them and selling them? It doesn't look *too* complicated, but I'm not sure I'd want it to be my first electronics project, either.


Answers:

1), Yes. The first day or so it worked OK after I adjusted the input level several times. Then it just started falsing all the time. I’ve been too busy with other things to mess with it at the moment. I believe all I need is a good band pass filter that would block everything except the voice announce range. I had difficulty with noise during my empeg install too and ended up running the amp. input under the rug and away from and 12v lines. There seems to be a lot of ignition noise in the car’s lines. It works great as long as the car isn’t running. Except what the heck would you need a GPS for it you’re not moving.

2), The mute line will stay active as long as there is auto coming in. You can change some component values to switch off instantly or wait a second or so. With voice input there is natural pauses. The switching off after the voice stops seems to work OK as delivered in the kit. I tried playing a Pink Floyd sound through the input and it did cut out during the pauses.

3), Yes, I believe if you just use the hijack mute on parameter and not the mute off parameter that would work.. With both the AUX will toggle on and off when the mute line goes high or low.

4), Yes, I have considered selling the assembled gizmo once I get it working. There are a couple Garmin forums where people have expressed interest in this sort of thing. However I don’t think many of those people have the technical skill to wire anything to their mute line. People here seem to be a bit more technical. The kit was pretty easy to put together. It was also pretty inexpensive so if you totally foobar it what the heck.

Thanks for the inquiry. This will help to keep my motivation up. I’ll let you know when I get the bugs worked out. Right now I have no time. I was going to try to get it working for the Indiana meet but that doesn’t look doable unless anyone has any suggestions on a good noise filter I could use on the input and the power line.