Re: 2465 Project, story so far.


Andy Warner
 

Do you have the service manual ? It talks about the boot process and where
things get stopped.

I was lucky enough not to lose my NVRAM contents before I was able to recap
and capture the nvram contents.

As I remember it, failing the RAM test (which includes the NVRAM) stops
things very early in the blinky-light POST cycle.

The section of the service manual is kind of oblique, IMO, but once you get
how they are trying to say things it gets better.

My scope had the GPIB option, and it failed a little while after my recap,
so I just removed it, since I know I would never use it. If you have any
options, I suggest trying to boot without them.

On Fri, Jun 5, 2020 at 2:55 PM <trogg58@...> wrote:

Hi all, another hopeful newbie on here, I found this site whilst looking
for some clues to attempt repair a 2465. I have managed to get it almost
back to life but now stuck, I wonder if anyone would be kind enough to
point me in the right direction.
Here is some background info, I have had the scope for about 12 years, but
not really had chance to use it, the magic smoke came out about 10 years
ago when I switched it on, it got put on the shelf due to lack of time and
left there. Now I have some time on my hands (due to being furloughed) I
decided to dig it out and try and repair it.
After opening it up I spotted that C1018 had popped and C1016 didn’t look
good so replaced both. C1020, C1052 and C1020 also had seen better days so
swapped them too, looking at all the other caps no obvious leaks or bulges
so reassembled and switched on, the CRT just about came to life and then
the smoke came out again. This time it was C1130, so I decided to re-cap as
advised on this forum.
I have replaced all the usual electrolytics on both PSU boards, with a mix
of Nichicon and Panasonics, and the Rifa caps, rebuilt and hey presto all
the voltages are well within tolerance, ripple all good too, but ….. the
post test gets as far as lighting all the front panel led’s and they stay
on, CRT comes up with a static bizarre display showing four groups of 1111
across the top and bottom a central vertical line of dots, a horizontal
central line of four groups of 4 dots then a top right to bottom left
diagonal of four groups of 4 dots, (picture posted under 2465 strange
display) only focus and readout intensity controls on the front panel
work., pressing the Delta T or V have no effect.
I do believe that I am the first person to effect any repairs to this
scope as all screws are present and there are no signs of any “after
manufacture” soldering of tampering, so its hands up I think I have done it
in myself.
Anyone have any ideas where to go first?
Thanks in advance…
John Carter



--
Andy

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