Turns out the board wasn't putting out +15v either. Either I was asleep when
I tested this the first time, or I ran it too long testing.
Turns out the 1n100 diode between the +15 regulator and ground shorted out.
This is a 100 piv switching diode. So far my searches for 1n100 have turned
up nothing, not even a 'discontinued' mention, except for NTE's cross to a
NTE109.
On the other hand, 1n914/4148's are cheap and plentifull (even CrapShack has
them). They are only 75piv though. My basic power supply knowledge is making
me ask:
1) Why the hell do we need a switching diode on the output of a voltage
regulator in the first place ? Isn't that what the regulator is supposed to
do ?
2) Since this is a 15v supply, is a 100piv diode necessary ? Even the 75piv
seems like it would be overkill. If it would be a bad idea to use the 75piv,
I'm assuming the answer to 1) will tell me, though it does appear the
Asteroids supply uses the 1n914
The only thing I can figure is it's a clamping diode, but I can't imagine
where the 75v+ spikes would be comming from.
-Chris
==========================================================
Chris Candreva -- chris@westnet.com -- (914) 967-7816
WestNet Internet Services of Westchester
http://www.westnet.com/
Received on Thu Oct 14 22:45:46 1999
This archive was generated by hypermail 2.1.8 : Fri Aug 01 2003 - 00:32:46 EDT