Tachometer selection

[Klimek]

To all who can help,
I am installing analog "steam" gauges in my Onex.
The problem I am having is selecting a tach that will work with both ignition systems through or with the toggle switches that are used for both the electronic and
magnetron systems.
Do I have to have 2 separate tachs, one small digital for one ignition and a primary analog tach? one connected to each ignition system?
The easy way out would be to install one small digital tach for each system..(cheating?)
How does this work? As I understand it, here are different pulses from different systems and the tach (or tachs) have to be selected accordingly.
Any and all help is greatly appreciated.
Frank
ONEX 090

[Sonerai13]

Frank,

At Sonex we pull the tach pulses off the alternator rather than either ignition system. The alternator puts out 6 pulses per revolution. Find a tach that will work with that setup and you're all set.

[Sonex1517]

Hey Frank

I am in the same place as you and while I found some possible models online, I cannot determine if they work as Joe described.

If you find a specific model that works please post it and I will do the same.

Here are some examples I found - not sure if they will work

http://www.vdo-gauges.com/instruments/by-type/programmable-tachometers/vision-black-4-000-rpm-2-1-16-tachometer-12v.html

http://www.vdo-gauges.com/instruments/by-type/programmable-tachometers/series-1-4-000-rpm-3-3-8-tachometer.html

http://www.vdo-gauges.com/instruments/by-type/programmable-tachometers/viewline-onyx-4-000-rpm-3-3-8-85mm-tachometer-12-24v.html

http://www.vdo-gauges.com/instruments/by-type/programmable-tachometers/viewline-ivory-4-000-rpm-3-3-8-85mm-tachometer-12-24v.html

Blue skies
Robbie

[Sonerai13]

Here are some examples I found - not sure if they will work....

Robbie and Frank,

According to the downloadable instructions posted on these web links, any of these tachs should work with a 6 pulse per revolution alternator. You just have to set the "dip" switches to the correct settings. Check out the instructions under the "downloads" tab about halfway down each page.

[Sonex1517]

Thanks Joe!

Robbie

[Klimek]

Joe, Thanks very much for your help.
This has made my life a bunch simpler!
Frank
ONEX090