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Other Stuff => Other Topics => Topic started by: scstill on August 02, 2024, 11:51:51 am

Title: 240Z - momentary wiper switch of latching relay for light control
Post by: scstill on August 02, 2024, 11:51:51 am
My son has this '73 240Z race car project with a tech question.
He wants to repurpose the wiper spray button (S3) to control interior lights
Push once they come on push again they go off.
He thinks he can do this with a couple of latching relays.
Schematic shown below is the first draft but it doesn't work.
Both relay switches have a high speed toggling going on (sounds like a old car radio vibrator)
Any thoughts?
Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: shooter on August 02, 2024, 02:24:57 pm
the short answer is KISS, just use a new 12VDC rocker switch up on, down off, no relays required.  there's a zillion "cool" switches


by end of day I might be able to sketch up complicated
Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: shooter on August 02, 2024, 04:31:42 pm
start here;


https://www.electronics-tutorials.ws/sequential/seq_2.html


don't have time to re-learn n hunt up the books, breadboards, etal....


should be able to use 1 or 2 relays with 1 NC n 1 NO contact each, your momentary contact will be the CLK IN, Q & /Q provide n remove power to lites.
Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: scstill on August 02, 2024, 05:43:57 pm
Thanks
I should rephrase, the circuit does work as when you push the button you get 12v latched to the function and when you push it again you get 0v latched,
BUT...
When the momentary is depressed it vibrates (buzz) until you release the button.
I'm trying to eliminate the buzz.
The buzz is created by the lower relay switch rapidly toggle which also is not latching (incorrect label in diagram)
Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: shooter on August 03, 2024, 03:32:24 am
put a blocking diode on the relay coil n re-check.
Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: ShoemanGB on August 03, 2024, 06:41:37 am
No to the topic, but how's that race project going?  I remember you posting about it some time ago and a few in process pictures. Love those old Z cars in race mode.
Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: scstill on August 04, 2024, 04:05:54 pm
Here is a pic from a few months back. He did all the metal fab in the car.
He is waiting to get the 2.8 engine (block and head) back from the shop
We currently are building a new wire harness
He has decided to go simple switch here
Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: shooter on August 04, 2024, 05:13:44 pm
here's the HP coming from, turbos, blower, NoS?
Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: scstill on August 05, 2024, 03:45:39 pm
normal breathing but with three carbs
car should be very light
another pic and the practice station.
Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: shooter on August 05, 2024, 05:31:44 pm
Quote
three carbs
always fun tuning multiple carbs, you get tthhhhiiiiis close then  :cussing:


both my last 2 cars were light, the WRX was "balanced" between the weight, HP n turbo, a true drivers car.  the EVO X was as light but 100 more HP, more torq, 20 more pounds of boost, was just a mean car, unforgiving as heck, but when it all clicked, the smile stayed plastered for days, the "lines" drove, are still there for playback in my head 10 years on.



Title: Re: 240Z - momentary wiper switch of latching relay for light control
Post by: rake on August 05, 2024, 09:49:29 pm
My neighbor and his son are putting a 6L LS GM motor in a 240Z for a street car!
I think his kid's gonna get a whole lot of tickets!   :think1: