24 Nov
2002
24 Nov
'02
4:47 a.m.
I've since pulled all the boards, installed a
M7625-AA (KA655) and
M7621
(MS650) 8MB memory card by themselves, and got a
chevron prompt. I also
got a memory error and a
message stating normal startup is not possible.
'show memory' showed
0MB of ram installed. I tried >another 8MB board
with the same results.
I also tried 3 different 16MB boards, but the LED display >showed 'F',
and of course, I didn't get a chevron prompt.
You know that the over-the-top connector used on the KA630 and
the KA65x are different? I don't know exactly what failure
you see if you use the KA630 OTP with the KA65x - but you may just
have found out!
It seems odd that a PSU could cause this problem and I'd be surprised
if *all* your memory boards are faulty (I've never found a dead one
even after they'd spent quite a while floating round the lab).
Antonio
24 Nov
24 Nov
10:12 a.m.
I don't know if anybody said it here yet (I try* to not read the
list all day long) but the voltage _drop_ of a wire carrying X
volts isn't X, especially for the purposes of calculating power
loss. One of those "You're Both right" kind of things.
- - -
A Phd friend of mine told me that he thought it was a mistake
to enlist in the Marines After getting his 4y degree instead of
before. On one of their tests they asked for the 'Three basic
laws governing electricity' or some such. He was worried that
he might get one of the equations wrong -- it might have been
all three. They wanted V=IR, P=IV, I=V/R... he gave them
Maxwell's equations.
John A.
*still trying and not always succeeding<g>
10:26 a.m.
Obviously what you state is correct. Otherwise nothing would work. However,
if the load end is shorted to ground, then the voltage drop across the wire
will be close to the source voltage, provided the power supply can provide
the required current. If the wire opens up then of course it will no longer
be carrying any current but the voltage across it will still be the source
voltage as measured from the source to ground. Regards - Mike
Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ, 07731
(732) 901-9193
----- Original Message -----
From: "John Allain" <allain(a)panix.com>
To: "CCTalk" <cctalk(a)classiccmp.org>
Sent: Sunday, November 24, 2002 4:12 PM
Subject: Re: MicroVAX II
I don't know if anybody said it here yet (I try*
to not read the
list all day long) but the voltage _drop_ of a wire carrying X
volts isn't X, especially for the purposes of calculating power
loss. One of those "You're Both right" kind of things.
12:11 p.m.
A non-text attachment was scrubbed...
Name: not available
Type: text
Size: 3400 bytes
Desc: not available
Url :
http://www.classiccmp.org/pipermail/cctalk/attachments/20021124/75925f37/at…
4:11 p.m.
Can somebody please enlighten me as to what a
'wire carrying X volts' is?
A wire completing an X volt circuit is probably better.
In other words the voltage drop along the 5V supply
line (meaning
the wire that should be at 5V wrt the 0V reference) is not normally 5V.
The point that was trying to be made.
Why those 3? The first and third are equivalent, so
why not have
R=V/I as the third one (give the equation in all 3 forms).
I think the point was that for Marines, where the rain moves horizontally
instead of vertically, and is made up of lead instead of water, the
equations have to be suitably simple for use in high stress situations.
I like Q=CV... hope to remember to ask that friend if it was that when
he returns to the US.
THX
John A.
25 Nov
25 Nov
1:39 p.m.
A non-text attachment was scrubbed...
Name: not available
Type: text
Size: 1635 bytes
Desc: not available
Url :
http://www.classiccmp.org/pipermail/cctalk/attachments/20021125/c606e355/at…
24 Nov
24 Nov
10:14 a.m.
I don't know if anybody said it here yet (I try* to not read the
list all day long) but the voltage _drop_ of a wire carrying X
volts isn't X, especially for the purposes of calculating power
loss. One of those "You're Both right" kind of things.
- - -
A Phd friend of mine told me that he thought it was a mistake
to enlist in the Marines After getting his 4y degree instead of
before. On one of their tests they asked for the 'Three basic
laws governing electricity' or some such. He was worried that
he might get one of the equations wrong -- it might have been
all three. They wanted V=IR, P=IV, I=V/R... he gave them
Maxwell's equations.
John A.
*still trying and not always succeeding<g>
10:15 a.m.
I don't know if anybody said it here yet (I try* to not read the
list all day long) but the voltage _drop_ of a wire carrying X
volts isn't X, especially for the purposes of calculating power
loss. One of those "You're Both right" kind of things.
- - -
A Phd friend of mine told me that he thought it was a mistake
to enlist in the Marines After getting his 4y degree instead of
before. On one of their tests they asked for the 'Three basic
laws governing electricity' or some such. He was worried that
he might get one of the equations wrong -- it might have been
all three. They wanted V=IR, P=IV, I=V/R... he gave them
Maxwell's equations.
John A.
*still trying and not always succeeding<g>
10:36 a.m.
Four message copies? New bug found with Outlook Express.
I can provide details if you want. Don't think you want.
John A.
6:26 p.m.
On Sun, 24 Nov 2002, Antonio Carlini wrote:
Which connector are you referring to? The KA630 and KA65x both use the
same console bulkhead, and in turn use the same two cables that connect
it. The KA630 and KA65x do of course use different memory boards, but the
ribbon cable that connects them is the same. Those are the only 3
connectors that I can think of offhand, except for the Q/CD bus
connectors...
I've since
pulled all the boards, installed a M7625-AA (KA655) and
M7621 (MS650) 8MB memory card by themselves, and got a chevron prompt.
I also got a memory error and a message stating normal startup is not
possible. 'show memory' showed 0MB of ram installed. I tried another
8MB board with the same results. I also tried 3 different 16MB boards,
but the LED display showed 'F', and of course, I didn't get a chevron
prompt.
You know that the over-the-top connector used on the KA630 and the KA65x
are different? I don't know exactly what failure you see if you use the
KA630 OTP with the KA65x - but you may just have found out! It seems odd that a PSU could cause this problem and
I'd be surprised if
*all* your memory boards are faulty (I've never found a dead one even
after they'd spent quite a while floating round the lab).
Well, *none* of the memory boards are faulty :)
For some reason, they seem to not be getting clean power, so they are not
working properly. I won't know for sure until I get my scope probes, but I
expect to see lots of noise on the power supply output that happens to
power most of the chips on those boards.
-Toth
7916
days inactive
7917
days old
9 comments
5 participants
participants (5)
-
allain＠panix.com -
Antonio.Carlini＠riverstonenet.com -
ard＠p850ug1.demon.co.uk -
n4fs＠monmouth.com -
tothwolf＠concentric.net