cheep A/F gague

Bochek · Post by **Bochek** » April 25th, 2006, 7:50 pm

not having any luck with feedback on this yet, i probably posted it in the wrong forum.

http://www.mx-3.com/phpbb2/viewtopic.php?t=51064

Bochek

Yoda · Post by **Yoda** » April 25th, 2006, 9:22 pm

Assuming that you are going to be using the stock narrow band O2 sensors. You have a cool flashing light on your dash that may look great at night in the parking lot of the local Tim Horton's but for tuning purposes it would be totally useless. By the time it show rich or lean it is already to late it the event has already happened. Also unless you have designed the circuit yourself almost all commercial products and schematics found in books and on the internet have a bandpass filter build into them to keep the display from flicking back and forth from full rich to full lean and the signal in most cars these days produce a signal that is a square wave rather than a sine wave. This is why you often see the Autometer A/F gauge constantly see display sweep rich/ lean and cycle faster as the revs increase. If you were to make a cheap wide band A/F meter where it would actually by of some uses I think it there would be more interest.

Bochek · Post by **Bochek** » April 25th, 2006, 9:40 pm

Yoda wrote:Assuming that you are going to be using the stock narrow band O2 sensors. You have a cool flashing light on your dash that may look great at night in the parking lot of the local Tim Horton's but for tuning purposes it would be totally useless. By the time it show rich or lean it is already to late it the event has already happened. Also unless you have designed the circuit yourself almost all commercial products and schematics found in books and on the internet have a bandpass filter build into them to keep the display from flicking back and forth from full rich to full lean and the signal in most cars these days produce a signal that is a square wave rather than a sine wave. This is why you often see the Autometer A/F gauge constantly see display sweep rich/ lean and cycle faster as the revs increase. If you were to make a cheap wide band A/F meter where it would actually by of some uses I think it there would be more interest.

The circuit uses the same ic as the commercial units, so its basically just the same thing, only a bit cheaper, and very small so that you can mount it anywhere.

Bochek