Hi, is it possible for someone to explain how the lower half of the circuit works? How do you choose resistors R3, R11, R5 and RH2?

 

how were you able to post on this thread? When I try to necropost, it gives me a message "this thread is over 6XX days old. Are you sure you want to post?" and I check yes, and it still refuses to let me post. Even on my OWN old threads! Yet I keep seeing people necroposting. It's not fair I tell you!

 

I ratted him out to the mods. They will give him a proper thread.

 

That's great, but some explanation as to why some users can necropost and other's can't, would also be great.

 

Welcome to AAC!

A thread belongs to the OP (original poster). Trying to take over someone elses thread is called hijacking, which is not allowed at All About Circuits. I have therefore given you a thread of your very own.

This was split from car temp control (fuel heater + ventilation control)

This thread is very old, which mean you were practicing the arcane art of necromancy, the revival of a long dead thread.

Automotive is not allowed on AAC any more. However, I suspect you are more interested in the regulators function. If this converts back to an automotive thread I or another moderator will be forced to close it..

For the purposes of discussion, here is the schematic you were asking about...

About post on a long dead thread, there is a box that says something like "I am aware this thread is very old and I want to post anyway". You must click this box to post, it shows it is on purpose instead of a casual accidental reply.

 

There appears to be 2 thermostats, ORed together so that either can activate the upper right transistor.

 

About post on a long dead thread, there is a box that says something like "I am aware this thread is very old and I want to post anyway". You must click this box to post, it shows it is on purpose instead of a casual accidental reply.

When I try to necropost, it gives me a message "this thread is over 6XX days old. Are you sure you want to post?" and I check yes, and it still refuses to let me post. Even on my OWN old threads! Yet I keep seeing people necroposting. It's not fair I tell you!

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