Anyone got one spare?
Cheers
Ian
Tacho with shift light wanted
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Tacho with shift light wanted
Involuntarius peristalsis rectum
"A true hotrodder wouldn't be content untill he had created a car so violent, so hairy, so totally sick that the very act of dropping the hammer would result in instant death. Anything less results in the need to go faster." - Tony DeFeo
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"A true hotrodder wouldn't be content untill he had created a car so violent, so hairy, so totally sick that the very act of dropping the hammer would result in instant death. Anything less results in the need to go faster." - Tony DeFeo
<a href="http://www.mybannermaker.com/" target="_blank"><img src="http://img153.imageshack.us/img153/1862 ... cebsh4.jpg" alt='Create your own banner at mybannermaker.com!'></a><br>
Re: Tacho with shift light wanted
will have look tomorrow think i got a couple
IF ITS ON WHEELS, LOWER IT!!
Re: Tacho with shift light wanted
Cheers Mr M. Had mine apart and checked through wiring tonight, and some voodoo happened. Starting reading a bouncy double speed for no apparent reason a few months back. Selector has always been on 8cyl. Put together and now seems accurate and stable. Maybe was poor earth or summit. Let me know wotchugot, still might be interested.
Cheers
Cheers
Involuntarius peristalsis rectum
"A true hotrodder wouldn't be content untill he had created a car so violent, so hairy, so totally sick that the very act of dropping the hammer would result in instant death. Anything less results in the need to go faster." - Tony DeFeo
<a href="http://www.mybannermaker.com/" target="_blank"><img src="http://img153.imageshack.us/img153/1862 ... cebsh4.jpg" alt='Create your own banner at mybannermaker.com!'></a><br>
"A true hotrodder wouldn't be content untill he had created a car so violent, so hairy, so totally sick that the very act of dropping the hammer would result in instant death. Anything less results in the need to go faster." - Tony DeFeo
<a href="http://www.mybannermaker.com/" target="_blank"><img src="http://img153.imageshack.us/img153/1862 ... cebsh4.jpg" alt='Create your own banner at mybannermaker.com!'></a><br>
Re: Tacho with shift light wanted
Got these havnt used em for a long time
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IF ITS ON WHEELS, LOWER IT!!
Re: Tacho with shift light wanted
Thanks Mr M for digging em out and posting up. I’ll hold fire for now while I get time to monitor my original.
Involuntarius peristalsis rectum
"A true hotrodder wouldn't be content untill he had created a car so violent, so hairy, so totally sick that the very act of dropping the hammer would result in instant death. Anything less results in the need to go faster." - Tony DeFeo
<a href="http://www.mybannermaker.com/" target="_blank"><img src="http://img153.imageshack.us/img153/1862 ... cebsh4.jpg" alt='Create your own banner at mybannermaker.com!'></a><br>
"A true hotrodder wouldn't be content untill he had created a car so violent, so hairy, so totally sick that the very act of dropping the hammer would result in instant death. Anything less results in the need to go faster." - Tony DeFeo
<a href="http://www.mybannermaker.com/" target="_blank"><img src="http://img153.imageshack.us/img153/1862 ... cebsh4.jpg" alt='Create your own banner at mybannermaker.com!'></a><br>
Re: Tacho with shift light wanted
bouncy and wrong speed i think is to do with the tacho circuitry being spiked with an over voltage from the primary
old style ignitions saw spikes in the 200-300 V range on the primary when the spark is unleashed on the secondary side, this is used to drive the tacho
modern ignitions can create spikes of 500 or more
the tacho uses a bunch of capacitors resistors and a comparator circuit. the capacitors around the circuit alternately charge and discharge to drive the the counting circuits used to move the pointer if they all end up charged at the wrong time tacho don't work properly again until it is switched off and they are all discharged.
i had this problem with my standard tacho
i put in a clamping diode and it went away
VS-40HFR40 zener Diode, Stud mount diode the R in the name indicates reversed the 40 is a hint at the 400 V capacity a 300 or 350 would also work R = reversed they swapped which end of the directional diode had the thread mounting section, from the normal standard
mount it into a bracket
bolt it to the motor
solder and wire on and run it to the coil negative
the voltage spikes seen by the tacho will never be greater than 400V
as per usual before you spend a tenner what worked for me may not work for everyone...... maybe it was just luck...
idea stolen from the Delco/GM/Lucas ignition set-up used on an XJS jaguar 6 and V12
you could also use the 10K resistor, i didn't bother
but good enough for a v12 jag.. good enough for me to try
the image below illustrates what is in the aluminium box with lucas sticker on a jag
the box costs £150-200 whats in the box costs £20 Lucas have the Jag people by the short and curlys look up lucas AB14
Dave
old style ignitions saw spikes in the 200-300 V range on the primary when the spark is unleashed on the secondary side, this is used to drive the tacho
modern ignitions can create spikes of 500 or more
the tacho uses a bunch of capacitors resistors and a comparator circuit. the capacitors around the circuit alternately charge and discharge to drive the the counting circuits used to move the pointer if they all end up charged at the wrong time tacho don't work properly again until it is switched off and they are all discharged.
i had this problem with my standard tacho
i put in a clamping diode and it went away
VS-40HFR40 zener Diode, Stud mount diode the R in the name indicates reversed the 40 is a hint at the 400 V capacity a 300 or 350 would also work R = reversed they swapped which end of the directional diode had the thread mounting section, from the normal standard
mount it into a bracket
bolt it to the motor
solder and wire on and run it to the coil negative
the voltage spikes seen by the tacho will never be greater than 400V
as per usual before you spend a tenner what worked for me may not work for everyone...... maybe it was just luck...
idea stolen from the Delco/GM/Lucas ignition set-up used on an XJS jaguar 6 and V12
you could also use the 10K resistor, i didn't bother
but good enough for a v12 jag.. good enough for me to try
the image below illustrates what is in the aluminium box with lucas sticker on a jag
the box costs £150-200
whats in the box costs £20 Lucas have the Jag people by the short and curlys look up lucas AB14 Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying