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Factory Tach question
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Topic: Factory Tach question (Read 8161 times)
hatzie
Junior Member
Posts: 771
Re: Factory Tach question
«
Reply #15 on:
March 07, 2015, 10:28:51 AM »
The tachometer signal is a variable frequency and amplitude pulse. I looked at the signal on my oscilloscope and it rings in decreasing amplitude waves after the initial pulse. The frequency of the largest pulse is what the tach uses to determine the RPMs. You will not measure any meaningful output on the tach lead with a basic multimeter.
Fluke 115 and Klein MM200 multimeters measure frequency in hz but the ringing will cause some variability.
An " Automotive" multimeter will be a better test tool. An automotive multimeter will have tach and dwell functions as well as ohms & volts-DC and maybe diode test and or continuity buzzer.
http://www.google.com/search?q=tach+dwell+digital+multimeter
From orbit on my Android.
«
Last Edit: March 07, 2015, 10:39:12 AM by hatzie
»
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76K20
Newbie
Posts: 26
Newbie
Re: Factory Tach question
«
Reply #16 on:
March 07, 2015, 08:16:44 PM »
Well got her fixed today. The problem was the wire from the distributor to the tach, ran a new wire and now she works like new. Thanks for all the help guys. Alan
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LTZ C20
Senior Member
Posts: 3795
"I'm here for a good time" -George Strait
Re: Factory Tach question
«
Reply #17 on:
March 08, 2015, 01:33:42 AM »
Good to hear.
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LTZ Cheyenne C20
hatzie
Junior Member
Posts: 771
Re: Factory Tach question
«
Reply #18 on:
March 10, 2015, 07:59:18 PM »
Good stuff.
From orbit on my Android.
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SVC & wiring mans --> Here
http://tinyurl.com/7387BRD-SVCMAN
or My Bucket @
http://tinyurl.com/SQ-SVCMAN
Parts & Illustr Books -->
http://tinyurl.com/SqParts
GMSTG Textbooks-->
http://tinyurl.com/STG-TEXTBK
Radio Manuals-->
http://tinyurl.com/DELCORADSVC
Dan75k20
Frequent Member
Posts: 269
Newbie
Re: Factory Tach question
«
Reply #19 on:
June 08, 2015, 01:21:26 PM »
WhT did you do about the resistor?
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76K20
Newbie
Posts: 26
Newbie
Re: Factory Tach question
«
Reply #20 on:
June 15, 2015, 07:29:49 PM »
nothing just ran a new wire.
Quote from: Dan75k20 on June 08, 2015, 01:21:26 PM
WhT did you do about the resistor?
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Dan75k20
Frequent Member
Posts: 269
Newbie
Re: Factory Tach question
«
Reply #21 on:
June 15, 2015, 07:31:33 PM »
Cool thanks!
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Factory Tach question