27 Jun
2023
27 Jun
'23
7:42 a.m.
Hey folks,
Now that I'm done moving house I have time to wrench on the 6150.
Before moving it worked; you'd power it on, the LCD status countdown
would get to an OK value, but the CRT wasn't legible. I figured I'd be
wrenching on the CRT.
Instead, now when I power it on, it powers on for a second or two and
then shuts off. I'm assuming this indicates a short or power-draw
somewhere. I've reseated the CPU and RAM cards, the peripherals, and
unplugged the hard drives (2x ESDI) and floppy in case they had a
fault that was drawing too many amps and causing the power supply to
shut-down. I noticed nothing on the CPU or RAM boards (exploded caps,
etc.)
What should I look at next?
--
-Jon
+44 7792 149029
27 Jun
27 Jun
9:34 a.m.
On 6/27/23 09:42, Jonathan Katz via cctalk wrote:
Hey folks,
Now that I'm done moving house I have time to wrench on the 6150.
Before moving it worked; you'd power it on, the LCD status countdown
would get to an OK value, but the CRT wasn't legible. I figured I'd be
wrenching on the CRT.
Instead, now when I power it on, it powers on for a second or two and
then shuts off. I'm assuming this indicates a short or power-draw
somewhere. I've reseated the CPU and RAM cards, the peripherals, and
unplugged the hard drives (2x ESDI) and floppy in case they had a
fault that was drawing too many amps and causing the power supply to
shut-down. I noticed nothing on the CPU or RAM boards (exploded caps,
etc.)
What should I look at next?
Well, if it has Tantalum caps, I'd suspect those. if there's
just one card with Tantalum, pull it out and see if it stays
powered on. Then, you can try to determine which cap is
bad. It could also be a power supply issue. Maybe a dummy
load that lightly loads all the voltages would be good for
testing.
Jon
10:12 a.m.
On Tue, Jun 27, 2023, 12:34 PM Jon Elson via cctalk <cctalk(a)classiccmp.org
wrote:
On 6/27/23 09:42, Jonathan Katz via cctalk wrote:
I would plug it in to the same place it was working to confirm a
known-working supply source longer works. I'd this is not conveniently
possible try a plug that has zero load on it. Eliminate the new variable
(new socket in new location) before start changing caps like its a
home.computer. the RT has a sophisticated power supply. There may be
redundancy built in as well.
Bill
Hey folks,
Now that I'm done moving house I have time to wrench on the 6150.
Before moving it worked; you'd power it on, the LCD status countdown
would get to an OK value, but the CRT wasn't legible. I figured I'd be
wrenching on the CRT.
Instead, now when I power it on, it powers on for a second or two and
then shuts off. I'm assuming this indicates a short or power-draw
somewhere. I've reseated the CPU and RAM cards, the peripherals, and
unplugged the hard drives (2x ESDI) and floppy in case they had a
fault that was drawing too many amps and causing the power supply to
shut-down. I noticed nothing on the CPU or RAM boards (exploded caps,
etc.)
What should I look at next?
326
days inactive
326
days old
2 comments
3 participants
participants (3)
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Bill Degnan -
Jon Elson -
Jonathan Katz