So from my digging...

This is what I bought:
https://www.aliexpress.com/item/New...acement-Wire-Probe-Connector/32869979505.html

Whitch contains an NTC-3470 Thermistor.
https://www.datasheetarchive.com/pd...1a1cf40bbf3e71a9d53e12&type=P&term=NTC%203470

That what I could find.

 

@AnalogKid
Hi.
Sorry for my abcense, i have been in hospital.

I ordered some LM139's at your suggestion. Just waiting for them to arrive. I also purchased a TIP32C.
As i said, the circuit is to run thermatic fans in the car. So as the temperature increases they stage on according to necessity. The cars operating temp is around 95c. It will go up according ambient temp and being a 4WD, stressfull terrain . There are 3 fans. 1 is controlled by the ECU.

You mentioned before, several issues with the circuit before, would you mind recommending correct values for me please?

Thanks for your help.
Daz.

 

Let's back up a bit.

There are two fan outputs in the original schematic. Is the goal here to have one fan come on at one temperature, then have the 2nd fan come on at a higher temperature?

If yes, then, when the 2nd fan comes on, does the first fan stay on or go off?

If not, then please make up a short temperature table showing what happens at which temperatures.

ak

 

Yes. Two fans. Two temps. Both on off independantly.
In actuality my circuit will be fans 1 and 3. 2 is ECU.
So first i need on at 100c off at 95c
Third, on at 115c off at 110c
But i can adjust these as needed.

Daz.

 

You still there @AnalogKid ?

 

@AnalogKid
I received my LM139's

 

So anyone able to pick up where this left off please.
I have all the parts and I am not sure how to proceed with them now.

Thanks.