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Hi Steve,
Do you have an estimate for the cost of the parts? Were they easy to obtain?
Dennis Tillman W7PF

Usually when this happens, your A5 controller board is
damaged due to leakage from 4 SMD style electrolytic capacitors.

This damage can etch out traces, and frequently etches the resistance
thin film off of two 10K resistors that are essential to the operation
of the DAC, which is essential to the overall function of the scope.

The first step in determining if this is what has happened to your
scope would be to look at the serial number on the front panel.
If your scope was made after B049999, it should have the SMD A5
board. If it was at, or before, that serial number, it should have
a through hole A5 board (which doesn't have this problem).

Next step is to take the scope out of its case, and look at the board
on the right side of the chassis. If it has any surface mount parts,
then it is the at-risk A5 board. Look specifically at the solder joints
on the board. They all should shine like little mirrors. If any have
a matte white finish, you have the problem.

-Chuck Harris

f5dog wrote:

Hi Dennis,

/g/TekScopes/files/DC508A%20Display%20Board

/g/TekScopes/album?id=42326

DipTrace was used to do the artwork. I'll also drop a PDF of the schematic for those that don't have DipTrace. The schematic has notes for the orientation of some of the parts that may not be apparent otherwise.

Steve WT0K

I have 2 ea. 2245A and a 2252 with the same odd problem, the AUTOSET button sends the 1/2 channels to the maximum (5V/2ms) rather than the correct values. I have never seen this problem before, now I have it on 3 units. any insight is appreciated as to what may be wrong here. everything else seems to work, and the cal is still good, just this odd control problem. I was trying to get these up and running for stuff day, so any help is welcome.

I will say that I am not a fan of the "control lag" in this series of units, waiting for a position knob or other control to suddenly start to work is not really great engineering IMHO. nobody that uses it for the first time ever thinks it is anything other than broken.

all the best,
walter (walter2 -at- sphere.bc.ca)
sphere research corp.

Hi Steve,
Can you include links to the Gerbers and the photos?
What application did you use to generate the PCB Artwork?
Dennis Tillman W7PF

Hi everyone. For a couple of days, some discrepancies happened starting my 2465B. The self test fails, and the 4 traces are no long vertically stable, whatever the time base, vertical gain and trigger settings. Any idea ? Thanks and regards. John.

HI everyone. For a couple of days, the self test of my 2465B fails on exercice 05. And an unstability of the vertical position of the four traces has happened at the same time, whatever the vertical gain, the timebase and trigger settings. Any idea ? Thanks in advance. John.

Hi all,

again a follow-up, this time on the battery-pack:

I used the solder lips to connect the rechargeable batteries, and used several layers of thin tape to make it into a similar unit.
To avoid a short between the lips and the outside and/or the batteries themselves, I shortened both the positive and the negative lip so they would stay on top of the positive pole.
This could be done because the new batteries were about 1.5mm shorter than the originals.

The new batteries also were just a bit thinner than the originals, so I could re-use the original positive circular terminal, even with several layers of tape around the batteries there was still enough room to insert the battery in the unit.
I used more layers of tape to secure the positive terminal to it's place.

Again, more pictures on this can be found here: /g/TekScopes/album?id=41029

I know, the tape I used is not so pretty as the original shrinking tape TekTronix used, but since I do not have this....

Next step: Find more info on the screen, and on the alternative one.
(I probably will go for the original one anyway...)

Un saludo,

Leo

Thank you Pete. I will do.
Is your 7B53A for parts or broken I presume... not a working one I hope ! :-)

Max

P.S. to contact someone in PM use the usual "Reply". You'll find little button option at the bottom right marked "Private". It toggles between "Reply to group" and "Reply to sender".

There is that.? Ran into that too.? But I always documented what I did on our servers, both on hard and soft copy.? That hard copy stuff was in a binder on my desk, and the soft copy was posted to our admin server.

Mark

The other side if the coin is it is sort of like herding cats, especially when you are coming along behind someone 5 years later after they have long since left the scene and NOTHING was documented :-P
-DC

--
Dave
Manuals@...
www.ArtekManuals.com

On 04/05/2018 09:50 AM, John Griessen wrote:

On 04/05/2018 06:54 AM, Mark Wendt wrote:

runs into the same issue as emacs (or xemacs) when trying to repair

a broken system.? It's generally loaded on a partition that

doesn't get mounted in single user mode, or there may be problems

with that partition during boot.
I use vim because I learned vi in 1985.? The partitions of servers are seldom separated now.? I think that reason to
use vi is over.? I doubt anyone under 50 uses vi at all.

Single partitions are great till a log file goes nuts and fills the entire partition.? That's why I always put log files on their own separate partition, same for the users home directories.? Making a server with just one large partition is just asking for trouble. Just because it may be the default in the installation, best practices for servers to this day point to making separate partitions or separate disks.

Mark

On 04/05/2018 09:50 AM, Chuck Harris wrote:

It was never a question of "not being sure" what mode
I was in, but rather one of "being sure" and being wrong.

It is simply very tiring to have to keep toggling back
and forth in the modes. It reminds me of working with
ed... which is what vi is: ed with a screen interface.

Given the choice between using vi or ed, I would rather
just use ed.

Most companies are very concerned about software that
exists beyond what their IT departments have installed
for every user. So, if they have installed vi, they
often won't allow a foreign editor, even if it is installed
in user space.

When I am repairing crashed systems, I am root and I can do
whatever I want. It has never made sense to me to use a
badly broken system to fix itself, so I use a "live" disk,
and my live disks always have the tools I will need, and
one of them is always jove.

If forced to use vi by the paucity of tools, or by force,
I will use vi. I fully understand it, but still hate it.

For me using vi is like pounding nails in my head. Sure
I could do that, but why would I want to?

-Chuck Harris

Each to his own.? That's the beauty of Unixy systems.? They're rich in utilities so there's always a choice.? What you like and what I like don't have to match.

Mark

On 04/05/2018 06:54 AM, Mark Wendt wrote:

runs into the same issue as emacs (or xemacs) when trying to repair a broken system. It's generally loaded on a partition that
doesn't get mounted in single user mode, or there may be problems with that partition during boot.

I use vim because I learned vi in 1985. The partitions of servers are seldom separated now. I think that reason to
use vi is over. I doubt anyone under 50 uses vi at all.

It was never a question of "not being sure" what mode
I was in, but rather one of "being sure" and being wrong.

It is simply very tiring to have to keep toggling back
and forth in the modes. It reminds me of working with
ed... which is what vi is: ed with a screen interface.

Given the choice between using vi or ed, I would rather
just use ed.

Most companies are very concerned about software that
exists beyond what their IT departments have installed
for every user. So, if they have installed vi, they
often won't allow a foreign editor, even if it is installed
in user space.

When I am repairing crashed systems, I am root and I can do
whatever I want. It has never made sense to me to use a
badly broken system to fix itself, so I use a "live" disk,
and my live disks always have the tools I will need, and
one of them is always jove.

If forced to use vi by the paucity of tools, or by force,
I will use vi. I fully understand it, but still hate it.

For me using vi is like pounding nails in my head. Sure
I could do that, but why would I want to?

-Chuck Harris



Mark Wendt wrote:

Hi all,

today the relais and NiMh batteries arrived.

Although the relais were the Pin-through-hole type, by bending the pins 90 degrees and shorten them a bit the relay was a perfect fit.
The good news: step-1 was successfully, now both channels have the same attenuation steps, so the next is rebuilding the battery and ordering the replacement LCD.

I read somewhere about a non standard replacement screen, somebody used a (cheaper, slightly smaller) screen from a different Tek model??
Before ordering the original I will look for that article first.

Some pictures about today's progress are here: /g/TekScopes/album?id=41029

un saludo,

Leo

On 04/04/2018 04:29 PM, cmjones01 wrote:

On Wed, Apr 4, 2018 at 09:28 am, Chuck Harris wrote:

The thing that turned me off vi was the way you had
to flip-flop between modes. I found that through a
typing error, or forgetfulness, I could easily get
into command mode, and completely destroy several
hours of work by touch typing text into the command
mode window.

Remember, vi is a modal editor. It has two modes: "beep a lot" and "delete everything". These are not mutually exclusive.

I'm a fairly basic vi user. I can drive it, but sometimes I'll step on a landmine and have to type esc:q! and start over.

Chris

Chuckle.? Yeah, vi has it's landmines for the casual user, but it's still a pretty powerful editor with all you can do in it.? The command syntax can get a little arcane but the things you can do with the commands are basically limited by your imagination and how well you know regexp.

Mark

On 04/04/2018 12:28 PM, Chuck Harris wrote:

I used to love it when a customer would insist that
I use vi at their shop. Since I was paid by the hour,
it would easily add a few thousand bucks to the cost
of the job by slowing me down.

The thing that turned me off vi was the way you had
to flip-flop between modes. I found that through a
typing error, or forgetfulness, I could easily get
into command mode, and completely destroy several
hours of work by touch typing text into the command
mode window.

I have never found it all difficult to find a copy
of jove (a light weight emacs clone) for any system
I have ever worked on... including windows.

-Chuck Harris

Strange they would force you to use their text editor to do your programming.? All the places I ever worked where we programmed for Unix we were allowed to use our editor of choice.? Be that as it may, jove is a good editor too.? But it runs into the same issue as emacs (or xemacs) when trying to repair a broken system.? It's generally loaded on a partition that doesn't get mounted in single user mode, or there may be problems with that partition during boot.? If the system boots to single user mode, vi is always available while other editors may not be.? If you're not sure what mode you are in, hitting the esc key a couple of times will get you back to the vi mode.? As a sysadmin, vi is part of your basic toolbox.

Mark

I suspect that 99% of members know this already - could be it's in their DNA - but for the remaining 1% of us who have this issue and have failed to find anything related via google, here it is:

I got two P6006 probes to go with some old 'scopes I've fixed. Chose them because they are 'of the period' and will match to the 47pF input capacitance of said 'scopes - only they didn't, in fact neither of them would adjust at all.

This style of probe is compensated by unlocking a ferrule at the 'cable' end and rotating the probe body. Took me a while to figure out how the thing was meant to work because unscrewing the body completely left me with two parts that couldn't possibly change the capacitance of anything relevant! Long story short, there is a third part that had become detached and was retained in the probe body, sitting there all innocent and looking like it was supposed to be just where it was when I peered down the hole.

This part is the tubular 'moving' plate of the capacitor, concentric with the probe's resistor and common with the cable inner conductor.
Normally it should be screwed on to the plastic end of the cable termination assembly. Use a suitable screw - M5 works, just - to reach down the barrel and grab onto the thread and pull the tube out, fasten it back on the end of the cable assembly, reassemble and bingo - a working probe.

Seems to me a small blob of something to lock the thread would be no bad thing but care would be needed to keep it away from the connection to the cable inner which is a bit of copper wire (perhaps a resistor lead?) half sunk into the plastic thread such that the tube's thread cuts into it as you screw it together, I don't know if there was supposed to be anything?

Adrian

On Thu, Apr 5, 2018 at 03:50 Lukus <lukusaurelius@...> wrote:

On Tuesday, I picked up a 2213A. While testing it, I noticed that the
trace does not fill the whole display regardless of position settings. I
tried messing around with the controls to see if I could fix it without
opening the scope, but I had no luck doing that. Today, I opened up the
scope (the cover won't come off all the way, but it comes off enough for me
to access the boards) so I could calibrate it. However, when I powered it
on, I found that a signal was displayed even when the trace was set to
ground. Adding to the confusion, the trace jumped between filling the
display and being too short; I couldn't figure out what triggers it.

Hi Lukus,

It sounds like the jumping might be a stuck or glitchy beam finder switch,
or you might have a power supply issue. Both are quite common in a scope of
this age.

Read this doc <
>, and get
a copy of the service manual. If you’re not familiar with how to operate a
scope, read through the operations manual.

Start by hooking a probe up to the calibrator, and see if you can get the
scope to show a good signal.
Work all the switches and pots and knobs several times, sometimes that’s
enough to clean the corrosion off the contacts.

Do you have a decent multimeter you could use to check the supply voltages?

Can someone help me work through calibrating this scope and getting it to

work properly?
By the way, this is my first ever oscilloscope.

Congrats on your first scope, nothing like a fixer upper to start with ;).

If you want more information and/or details, please let me know; I would
be happy to provide them.

See if the service manual doesn’t get you started on diagnosing what’s up,

if you get stuck it’s probably most expedient to post a video of how the
scope’s behaving.

Good luck,
Siggi