Oscilloscope refurbishment


#21

Sorry I didn’t have the time to embed the photographs where they’re supposed to exist within the original text.

Mike is a freakin’ wizard btw… Awesome guy.


#22

Holy crap, wizard is right!


#23

Nice work!!!
I have TDS310 that is still luckily running fine (very low miles) but one day I’m sure I’ll have to deal with something breaking on it…
Your posts makes me feel more confident about having to repair it…


#24

Thanks for posting these updates, Jason. Fascinating repair log.


#25

Ingenuity in Action!


#26

We’ve run into a snag, I’ve got a bunch to elaborate on but we haven’t put the GPIB together yet and we’ll have some actual info to update once we’re done that. We’re going to be doing an Oscilloscope meetup at our space Saturday and we should have the GPIB ready by then. So hopefully by Monday I’ll have a really cool second update on the refurbishment. @SDY, we’re hung up re: the burner. So I’m going to hold off on coming in to VHS to grab it until we’re over this latest hurdle. We’ll let you know if we can use it in the near future. Thanks for your offer, we’ll keep you posted!


#27

Jason, communicate directly with me about the programmer. You have my coordinates from when I passed on electronics parts, about 2-3 years ago. If not, try 604-676-0433.
SDY


#28

Jason,

a look at the datasheet for the DS1650Y NVSRAM (
www.dataman.com/media/datasheet/Dallas/DS1650Y_DS1650AB.pdf )
indicates that it is a lithium-battery-backed-up CMOS memory, with a
page-protect configuration register. This register is not programmed
like an EPROM, but rather by a specific sequence of normal memory
reads, using A15-A18 to provide the data. The data in the CMOS RAM is
written using normal memory writes, provided the page in question is
not write-protected. The battery is good for 10 years, so it’s
probably dead by now. People have brought similar NVRAM chips in Sun
Microsystems computers back to life by exposing the battery
connections inside the DIP package, and connecting a new battery
across them.

  • William -

#29

My Monday update is less cool than I’d hoped for, NOT due to a lack of results. We simply ran out of time due to a busy weekend.

Part of the push to resurrect this oscilloscope is because we’re developing a new class on oscilloscope best practice (operation, maintenance and safety). So Friday evening I spent the night assembling the GPIB interface, one of our members (Mel) had steered us towards this one http://egirland.blogspot.ca/2014/03/arduino-uno-as-usb-to-gpib-controller.html

Then Saturday we did a dry run on the course. We use 3 scopes, a digital scope, an older analog scope with a CRT display, and a battery operated portable scope. After giving us a couple of hours of instruction, Mike (both the wizard who repairs scopes and our instructor) set us up with a series of “posers” where we needed to figure out not only what was going on in the circuit, but why in most cases we couldn’t read anything on the scope.

We learned quite a bit about what works in the class, and we’ll most likely break it up into a 2 or 3 day class as it was quite long. But the main reason I wanted to mention it to you guys was because Mike referenced your Rigol scope wiki regarding precautions while operating the machine.

https://vanhack.ca/doku.php?id=tool:rigol_mso1074z

We’ll be offering this class in the near future to the public, but if you’d like to see photos of what we were doing you can check them out on our Facebook page (under FVMakers).

Mike is back at the repair but we don’t have the GPIB fully functional yet. We’ve also got more questions than answers at this point, so I will post as soon as we make a discovery. This evening we should probably have the GPIB up and running and it’ll expose a lot.


#30

I forgot to mention, if you check out our photographs you’ll most likely notice our function generator as well as a PC based logic analyzer on the table. After 6 hours we didn’t even get into looking at them, so we’re most likely going to break our future class up (may even have to change it to a general diagnostic tools class instead of calling it an oscilloscope class) as we’d like to include these tools.


#31

Thank you for your comments! Back when electronics was my profession, I routinely copied similar NVRAM chips with an EPROM programmer. As I recall, the “program” voltage pin was NC for the NVRAM and so the read/write process was just like writing an EPROM.

As for exposing the battery, and connecting another, I can’t possibly be proud of that work so I wouldn’t consider that.

When/if I manage to solve this CPU/display board problem, I shall look into this much more deeply!


#32

If I may suggest, be pro-active about replacing the SMD electrolytic caps…before they spill electrolyte throughout and (yes) under components where it quietly dissolves traces & vias.


#33

Christmas came to the FVMS, a bit late but it came before New Years and that’s pretty darn awesome!

Thanks Santa Mike for your repair (which we’re going to post on the forum, it’s a bit of a write-up though and everyone’s busy with the holidays) and thanks VHS for donating it to us!


#34

That’s so rad. You’ve got a better scope than us now, but definitely earned it with your sweat equity :slight_smile:


#35

Well, we’re open to the public so technically we’ve all got a better scope. It’s a bit of a drive from Vancouver but if any of your members ever need to use it it’s here waiting for you.