Hi check out what I scored from the dumpster. the same dumpster that we scored all that gear with the other month that all that our Schaffner stuff and by the way did get another Schaffner module. Awesome! this one CR NSG 203 a line voltage variation simulator. It simulates like dropouts and line.

you know, like brown outs and stuff like that and for its it's got a weird-ass output connector. so yeah, not terrific. Anyway, just thought I'd show you that one but ya might do that in a future video. But today we're going to take a look at this Tektronix Tds 540 d 4 channel 500 meg 2 gig sample per second digital storage oscilloscope with GPO technology and the this series dates from the late 90s so it's actually 98 I believe So it's like 20 over 20 years old now and these particular models aren't hugely popular on eBay In fact, a lot of them are faulty.

so I think like this particular series or a several of the very series of the old are tedious scopes. Um, yeah, they might have a a higher than normal failure rate, but anyway, we can see that the BNC is down there looking pretty good Nick when you are when you're getting a scope secondhand if you can get and if you're selling a scope secondhand by the way, always include good close-up photos of the B and C and it's got all the active probe attachments on there so it looks in pretty good Nick part from a couple of knobs that are Gonski but you know it's not a problem. A little bit of yellow in on the plastic and stuff like that, but this is a it's a fairly powerful scope. 500 Meg bandwidth for channels to get samples per second and that's enough fitter for the 500 megahertz bandwidth just to really the 2 G samples per second.

But yeah, this is you know it's nothing to sneeze at, but what are the odds of this working? Yeah I didn't I don't know I did ten to one I'm here all week. Get it tender Anyway, a floppy drive definitely dates this thing and it's apparently compatible with the I Omega zip drive. Hands up. If you remember the I Omega zip drive for storing large amounts of data, we're talking about up to eight Meg of sample memory in this thing which doesn't sound like a you know, a huge amount by today's standards.

but back in that you know, twenty years ago that was a massive amount of sample memory. But yeah, a lot of people didn't like like the usability of these things. but you know it, you wouldn't complain if you've got a work in five hundred Meg for channel while scope with a decent sample rate and eight mega sample Mary You wouldn't kick it out of bed. By the way, if you're wondering why the video might look a bit funny, it's because I got rid of the other mixed color temperature studio lights here.

so I'm waiting to get a it's a new one so did ya? Sorry, It just looks pretty crappy at the moment now. these actually did. Incoming color screen models are not showed I think this one is I think it's a monochrome one, but they came in color LCD shutter our technology warranty void if broken. That's okay, but the other warranty void stickers look busted.

There's the serial number for those playing along at home and there's a 240 volt model of course. and we've got all the records that does stuff it's got. Look at this. a VGA output nice.

And of course your obligatory GPIB and option two em down here is apparently are the two Meg memory. but on this particular model, that's actually eight Meg I believe. and it's also supposed to have an internal hard drive as well. Okay, even though I've recently had a lot of problems with powering up old gear with the magic smoke release, I'm gonna power this thing up.

Let's go here. We go here we go. Fans are spinnin lights are on. Nothing on the screen yet I Thought I Heard hard to seek.

no no screen zip-a-dee-doo-dah Oh no. Hang on. No, we do have something. Oh wow.

not the set night everything's collapsed. Look at that. Let's see it. Whoa.

Oh it's like hey, it looks like it went through itself. Tess Yeah yeah, look hang on. Oh yeah. Channel 1, Channel 2 Channel 3 those lights are coming on.

So I so looks Like the processor and everything working but the screen. It's cactus. Just for good measure. We'll give it another cycle here and see what happens.

Yeah I don't have a like extensive experience with these I Used one of the more higher-end the 700 series model a bit, but never really used the 500 series. I Don't think and I Don't believe there's a lot of affinity for these so you know it might be a good one to try and pick up. You know it, like if you need a decent bandwidth or something for not much dollars. But yeah.

anyway, the screens gone ski. Yeah. but I reckon the processes are working because it seems to go through the motions. Yeah, there we go.

Yeah, it's going through the trigger thing. We can select the different channels. So yeah. last calibrated in 2007.

Yep, Okay, so we have a scream problem here I Have no idea what that is. But the good thing about a unit like this is that has an external monitor output. It's got a VGA monitor output. so let's switch it on with an external monitor hooked up and see what we get.

Yeah, and what's it gonna do? Because as I said, like those front panel controls were working, we're not getting anything yet. Hey Tektronix Tedious runtime environment Java Powered Fantastic. Java Based oscilloscope. When did they stop that? anyone? yet? There you go.

It's um, it's not color. Its monochrome of course because this is a dry. Believe this is a this is a monochrome model and this is yeah. I Heard the relays click.

it's doing stuff 100 K samples per second and we're in like Flynn think of that there it is Wow Options: 1f HD to M91 Copyright: 91 to 98 On to power on self Chest test check past push, clear menu to proceed. Where's clear menu? haha Beautiful. Alright, let's well. he probably should like cook up a test signal see if we get something.

Well that's interesting if I touch the probe like that. Bingo. it's popping up. Yeah, we're getting something that's going to be your 50.

Hertz So I could scale the horizontal for that. Yeah, we're getting something. I've got some horrible persistence armor DP OE type stuff one Kilohertz test signal. Winner winner chicken dinner.

You know it's it. The DPO button. turn that DP Oh rubbish Off there we go. Now if faster update and weak hitting bugger all the sample of the bugger all memory though it's the what is it the the the to K of memory or whatever.

but there you go. Vectors, dots, intensified samples, infinite persistence. It's what we what we had some sort of our there we go It was set to half a second variable persistence sir before so yep I think that was what was turned on there. Oh look we can set color display here and it.

but it did you. it. made color. It's just like a black and white.

a grayscale thing. So the amplitude looks right there. It's ash. supposed to be 100 millivolts per division times 10 probe.

and it's it's looking fine. I Haven't compensated that probe on this scope. Of course that's why we see a bit of overshoot there. But but yeah, um, that's working.

Okay, just plugged it into Channel two. I Just ran the auto set and why not? That's Channel 2. It works. It's not the slowest B/c they like.

the user interface on this is little bit clunky, but you know you get used to this sort of thing. So Channel 2 is fine. Channel 3 Trigger: There we go. Yeah, that looks good.

Amplitude no problems. Three channels working. Rule number four work. Yep, Yep, we have a 4 channel scope.

Winner winner chicken dinner. 2 gig samples a second. and if we go faster et. phone home, we're in acquittal.

80 stands for our equivalent time sampling of course. So it's doing that. It's requiring multiple acquisitions there to get that. It's just our trigger level there.

Hey Beautiful! So this thing's working. A treat. No worries whatsoever. I Have no doubt that if I put a 500 megahertz signal into that, we'll get to our 3 DB bandwidth.

So we're back in our DPO mode. Now you can see the noise on there, so let's go into our Channel 4 Oh Vertical menu I Can't press the Channel 4. I'm so like I'm used to like pressing like the Channel 4 button and then double pressing channel 4 to turn it off for example. And but no, you've got to dedicate a waveform off a button and then you've got to hit the vertical menu.

So just press in. Channel 4 doesn't bring up any of the channels, doesn't bring up the channel menu. You've got to actually press the vertical menu like that to actually to bring it up. It's just a silly user interface really is, so we can just knock the bandwidth down on that.

There you go: 250 Meg 20 Meg 250 lower a bit more and 20 mega. Bring that down a treat because I've done a whole video on that. The wider the bandwidth, the greater the noise appears. You've got to love the hard copy menu over here.

Think jet inkjet printer desks yet high-resolution laser jet Epson 9 and 24 PennDOT matrix What else we got DP Thermal with GPU 411 don't know what that is Pc X Paintbrush a format and tiff tagged image file format looks like that's my default bitmap or EPS nice int Elite image object format interleaf and Hbg or color plot Beautiful. Yeah, it looks like we can now save into the internal hard drive there as well. Neat now. I Don't know these units offhand, but does the operating system for this actually run from the hard drive? Or is it like embedded in some non-volatile memory on the board? Yeah, I Then don't know I Think the hard drive is optional on this, so it's probably just for storage I Suspect Ok, let's go into the menu here.

see if there's any yard diagnostic errors. Select all tests. Ok. Error Log Here we go: Two thousand, Two thousand seven storage error.

Okay, so there would be hard drive excessive probe gain error, but come from, you know there's some spurious thing when they had an active probe hooked on something like that. Perhaps that's really quite good. Anyway, select tests all and I'm gonna execute all the tests I'll disconnect the probe run. huh? Oh yeah, there it goes.

Yep, Oh whoa. Is it supposed to repower like that when you run the internal tests there? Any other Java based testing instruments out there scopes and things? Is it gonna reboot and run the tests? Well, yeah. I'm not sure what happened there. It rebooted I did nothing.

so one more time for the dummies. I Guess there he goes again. it just reboots. Alright, so let's crack this thing open.

See what's what? Oh Beauty. We're in like flame. Oh look at that big hate sinks on those massive Asics Wow Well at the design review meeting for this thing, they went well. you know I look at all this all these heat sinks that's gonna need a lot of air.

So ah bugger it. let's just install this thing. Unbelievable. Look at the depth of that thing I mean it's it's that's just nuts.

A 24 volt uh, smart fan made in Thailand Wow look at, you know and a huge big plastic guard over that - - as like funnel air directly where it needs to come from. Well this is just one amazing piece. Look at all the hardware in this. That's all.

kind of what that you know. Tons of seven four series logic in this, but of course lots of custom Asics and programmable logic and stuff like that. and the date codes on this era 1999 So yep, almost 20 years old. But yeah, the various option boards on this thing.

this is obviously the front end. Here's our front ends down here. and then we've got our our four channel acquisition. So we're going to have our Wah ADCs and then our sampling controllers got our sample memory.

Of course that's our base sample memory, but there should be an expansion board somewhere. I Do like how they've look gone on both sides. power supply in the middle like this and they've jumped these jumper balls. Plus these ribbon cables.

Not sure why they went for ribbon cables here and a jumper board up here. Not sure what the deal is. Yeah, it seems a bit strange, so it's kind of an unusual construction. This is obviously all of the processing grant and I will put some out high-res photos on the Eevblog flicker account.

Yes, do we use flicker and that's where I put all my photos and I leaked them over on Naive Elog dot-com as well. You see, there's just a ton of stuff on here. Dallas Set Classic Dallas Semiconductor Non-volatile SRAM Here these have included batteries. Why again? Date Code 9 2011 2000 1999 We got a party like it's 1999 and yeah, I'm sure the party's over for the batteries inside these things.

They do famously. Lastly though, I think they only had a guaranteed life of like 8 to 10 years. but they do typically last for much longer than that. But yeah, this is like Border almost 20, like 19 years old now.

so it's almost practically 20 years old. It's it's really getting to the life of it. So yeah, unfortunately, the non-volatile memory may not be that great. We've got a this switch down here is actually a non-volatile memory protection switch so you can actually get through a hole in the side of the case and you can poke in there and actually activate this switch if you want to.

You know they calibrated or or reset factory reset it or do whatever bunch of dip switches here. I Think one of them does a test pattern according to the manual which will try and use two. Well, we could use if the if the damn CRT worked anyway. But yeah as a whole bunch of stars, some unpopulated parts in there.

Ooh and looks like we've got some sort of little post. you know, power-on self-test maybe error? LED display or something like that. Check out this footprint down here. Absolute classic dual footprint in there.

They went well. If you can't get this package part, then we can always get the one of the larger package part in there and substitute that in production. Once again, some unpopulated parts in there. three you want and we have a fourth one like it's breaking the symmetry.

don't like that. Bad vibes and you've got these custom Tektronix parts of course. And yeah, if the magic smoke skates from though as well. Yeah, good luck getting a new one.

Would they still sell replacement? No, they wouldn't. Come on now, you'd have to salvage apart surely. So the front ends down here inside this nice nickel screened can down here. I Really like that this flat flex cable going off that's going down to the active probe terminals on the front and you can see that they're fused as well.

So that would be the four fuses for the four individual channels. Too big as you want to stop the idiot users from. you know, plugging in something that they shouldn't and you don't want to bring down your scope. So yeah, no problems whatsoever.

We can see some serpentine traces here. This is to match the length of course for each channel because this scope is being a very like more Back in the day was a very expensive high performance scope and it has specifications for like channel channel to channel skew and stuff like that so it's highly suspect. So I think it I think it was in the order of like five picoseconds or no fifty picoseconds channel channel skew or something like that and that's how they get it. So there you go.

it looks like is that it's all going into this one chip. I'm going to have to because we do have the service manual for this thing with the schematics I believe although it is the B model for the schematics instead of the D but and the IDT SRAM's up here. these are like very small so these are the just the what eight kilobytes or whatever DPO like. like the fast memory designed for fast updating if you want your huge 8 Meg sample memory that's on your other board.

Bugger off and we were very comprehensive trigger outputs here. Fantastic! Little coax is going up to the B and C's on the back panel and lots of good old national semiconductor parts inside this thing. Of course the unfortunate thing is all the CRT driver stuff is all wedged in the middle of this thing so like I can't I can't even see any of it let alone access it. So yeah, what a pain.

So to get to all that stuff we have to get into this can right in here. That's just hard to say that one of the things you could have done to this with a failed CRT Of course you can try and fix the CRT drive or whatever's are gone wrong with that, but of course the scope works. The Gie output works. so I thought maybe you know if you wanted to, you could simply replace the CRT with a little what is that you know? 6 inch, 7 inch or whatever VGA compatible monitor or something like that.

but I'm not sure that's possible because this is all integrated down here and one huge big molded part of the show. Z Wow, it's just like yeah, you can't just like rip out that and attention to detail. Look at this little plastic retainer clip they've put in here just to keep the ribbon cable down. It's presumably for when you slide the case on.

The ribbon cable flapping around in the breeze could get caught and crushed and stuff like that, so that's just keep it in place. It's actually very nice, but it's a rather annoying when you want to take it apart. Now, the really interesting part about this is that it doesn't have any screws on this top board. As you can see here, it's held in place by these plastic clips, which then you see that there's a slot on the end of it.

So when we actually pull this board out, you'll notice that there's a riser board over here that it plugs into. I've disconnected all of the various cables here I Think so. in theory it should. Just yeah.

Oh, that's a bit. that's actually a bit. Lucy that's Lucy Goosy. that's just flapping around in the breeze there.

But oh yeah, just comes off like that. It's so great and that just comes forward and lifts out. Wow. I'm impressed by that.

There's your hard driver. Yeah, that's your hard drive board. Cirrus Logic Chipset down in there and there is your main processor board. Nothing on the back, cept or bypassing.

You'll notice all the traces going vertical. Or you know, they're predominantly vertical on the one side. And of course, they'll be predominantly horizontal on the top side because this is a multi-layer board. Yeah, there's some stuff happening in between, but that's your traditional top bottom alternate routing sacrifice - the teardown gods.

Well, I'm actually becoming super impressed with the construction of this thing. Very nice. Warned in danger Will Robinson It looks like we're just going to be able to take some screws off the top here. It took me like less than a minute to whip out those boards, didn't need any screws at all to take them out, and I've got access to the internal high-voltage stuff.

Absolutely brilliant. The only downside of this, of course, is because you've got to take out all the ribbon cables and everything else. You can't access any of the stuff in here. any of the driving stuff for the CRT with the processor board running and the thing powered up.

so yeah, you can't be like feeding data into it. Ah, beautiful, we're in! Fantastic! I Love this! Well this looks pretty clean. There's not a huge amount of dust on there. You can see some down here.

You know there's some collected on the grill over here where the fan has come through. Haven't had a look at the CRT part of that yet, but this is of course the main switch mode power supply. Check out the old school dip riser board controller board here. Phir switch mode controller Yes, all the caps top quality.

That's a Nippon chemi-con for those playing along at home and we've got nichy cons down on the secondary side of that output. You know the main DC output side. Nice little temperature sensor on the heatsink down in there like an that actually. I Do believe it's possible to do the CRT replacement with an LCD thing because the while the or the like the outer molding for the CRT is all integrated into the chassis Here the CRT does actually screw and pull out.

You can see it in the assembly diagrams in the manual screw and pull out from the thing so it's left with sure. you've still got the outer thing on here, but there's no reason why if you had a suitable size LCD you couldn't sort of retrofit that in and and connected into the VGA output. now. I've actually done a quick visual inside the CRT here, which is when of course, the problem is almost certainly residing.

it wouldn't be on the driver side, and there's nothing really obvious from a visual standpoint except for the fact that the ribbon could the drive a ribbon cable going over I suddenly like push that back in and it seemed to be out a little bit. so I'm not sure I didn't really get a feel for how far it was out, but it was definitely out. so I'm not sure if that's a problem. I'm tempted just to put it back together quickly and and see if that actually was the problem that somehow the ribbon cable do like the tension somehow would like because it's not hard to pull that out.

it's not a large number away connector. There's not a huge amount of friction force on those pins, so maybe I don't know we're putting this in may have caused a marginal connection in there. But anyway. hmm, it's nothing visual and no.

I don't see any dreaded reefer caps in here, so I'm not sure what brand those ones are. So once again, there's nothing in the power supply section. I've had a reasonable wire visual on that, like the five volts and the 12 volts and other you know, negative 12 or 15 whatever for all that stuff for the analog and digital sections, all working fine because all the channels are working fine and all the digital circuitry is working fine in the video processor and everything outputs fine. It's just that the CRT doesn't work so most likely something wrong in there.

So one thing I'm not seeing on the power supply though and that's any convenient voltage test point. So I haven't read the manual yet and seen now like you know the service part of this for the power supply to see like where the where it recommends the voltage taps are or what rails is just I don't know, maybe I'm missing it, but it doesn't really seem to be any indication. that's that's a bit annoying. I Of course much prefer designs where you can just open them up and you don't need the service manual at all.

and there's a test point. it says 5 volts, it says 12 volts plus minus 15 volts and you're just not only of a little you know, turret test points or whatever, but they're labeled on the silkscreen and everything else so you know exactly what's what. Maybe I'm having a Stevie Wonder day but I can't see it and again very small touches that I do. Lee Note these little like holders for the metal panel here on molded into the Chevy I mean that's fantastic up on the CIT there too.

so when you push this in and slide it backwards it it's held in place along there Just fantastic systems engineering look. They've even got the PCB supports molded in to the chassis. Unbelievable and it took like a minute to put that back together. That's just unbelievable I Don't expect it to a fix that, but I Just wanted to try to see if it was that ribbon cable I Doubt it.

Do you believe we got some sort of electrical or component fault on that CRT section? and now you can just see it? Incredibly faint. not same issue. So let's actually just run the display test on this thing. Apparently you got to put six and seven dip switches down here to open, pair it up, and then go into the utilities menu and you select instead of all that we're doing before you go down to display here.

and then we need to compass it. There you go, that's what we want and then execute okay, confirm, test, and Bingo. Look at that Ah, thing of beauty. Fortunately, we don't get that on the CRT.

Now the thing is, this thing is color. It has the ability to run color so oh whoa. We're getting a blue background there now so that's like that's really interesting. Wow Anyway, I Didn't want this to turn into a repair video today I Just want to do a quick teardown and pair up an analysis of this thing and it seems to be a fully functional 500 Meg 4 channel scope.

We're fully optioned up with the 8 mega memory and everything else. As I said, still quite a powerful scope even today. So yeah, that's very nice. So even if you only had to use it with an external model, it's a bit annoying because you know you've got to use all the menu buttons and yeah, you know they don't visually line up.

Yeah, it's It's still a winner by the looks of it. So let me know what you want me to do with this thing. You want me to track down the fault in the CRT trying to repair that or is it a good candidate for like some sort of us, you know LCD Replacement Modern LCD replacement or something like that because that would be nice cuz yeah, to be lighter weight, lower power, modern, and reliable. All the rest of it.

Um, dad, maybe you could, you know, turn down the fan a notch and stuff like that. So let me know what you want to do. and if you know of anyone I haven't looked yet. but if you know of anyone who's retrofitted one of these with an LCD let me know anyway.

I Hope you enjoyed the video. If you did, please give it a big thumbs up and as always you can scuffs down below. Catch you next time.