Component Exchange question

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91 XR7

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Hello all,

I've been working on a small circuit which is posted in the Automotive Electronics section and want to try and minimize the components in the circuit. So i have a few questions.

The Circuit i have as of now, hand drawn to boot, is
**broken link removed**


1) I have gotten rid of the relay to switch the Negative (Fan #1) trigger to a positive using a PNP MJE2955T i had on hand, But at this time, only using a 22K pull up, and a 2.2K trigger on the base. the MJE2955T may be over kill for the circuit thou, the other option i have for a PNP is a 2N3906, but i don't think that's enough? Options?

2) Now in the circuit there is two Darlington pair like setup using a 2n3904 and a BC140, Could i replace those for say a TIP120?


The circuits on my diagram are based off of Bowden's Hobby Circuits websites Delayed On and Delay Off circuits.

Thank You
 
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