Fiddling with the dividers was a disaster. A complete dogs breakfast. Every time I touched one, I'd throw the other completely out of kilter.
So I tried using the battery for a -1.5 V rail. (After a lot of swearing and burnt fingers while I put the resistors back in the board.)
Not a bloody thing. The reference regulator couldn't manage the extra current the hall sensor drew at the higher voltage AND charge the "soft start" caps at the same time. Would only work if I connected the hall sensor after the board stabilised.
Back down to Jaycar for a 7805. Bolted it back to back with the 7812 and soldered it's in leg to the out of the 7812. (Bit rude to put it on the 24v line and a convenient place to mount it anyway.)
Success. Finally. -ve 100 mV on the hall output. 100 mV - 22 V at the motor output.
Powered by DCForum+ Version 1.1 Copyright 1997-2002 DCScripts.com
Software has been extensively modified by the DU administrators
Important Notices: By participating on this discussion
board, visitors agree to abide by the rules outlined on our Rules
page. Messages posted on the Democratic Underground Discussion Forums are the
opinions of the individuals who post them, and do not necessarily represent
the opinions of Democratic Underground, LLC.
Printer-friendly format
Email this thread to a friend
Bookmark this thread
(1000+ posts)
Send PM |
Profile |
Ignore
