Suggestions for a good second-hand LA?

[mbalmer]

but if i'm at OP's position i will try to fix the existing modules first. its a surprise all 5 modules fail. do they fail the same test? i'm not familiar but maybe you can open up and switch parts. if all repair attempts fail, only then spend extra money. ymmv.

No — each module fails a different set of tests, although there are some that are disturbingly common.

Board A fails the comparators and ZoomChipSel tests.

Board B fails comparators and calibration.

Board C fails VRAM (both serial and parallel) and comparators. 

Board D fails VRAM, all Zoom chip tests, and one of the inter-board tests.

Board E fails every test except for chip registers, comparators, backplane clocks, the ICR test, and the arming test.

So it seems that while the comparators test is a point of failure, it’s definitely not the only one.

I’ve spoken to some others and they seem to believe that anything in the 167XX category is a ticking time bomb — it’s not a matter of if, but when it fails.

Apparently the 165xx line is less prone, but it can still happen, and I was looking at some boards on eBay that had shockingly green-looking vias around their RAM chips. It’s why I’m leery of it. I essentially have a mainframe with a 500MHz 2-channel scope in it and nothing else to show for it.

It’s also why I’m looking at the Tek options — while I like the setup of the HP systems better, if the Tek stuff is more reliable, I’ll take that.

[gslick]

It’s also why I’m looking at the Tek options — while I like the setup of the HP systems better, if the Tek stuff is more reliable, I’ll take that.

In the Tektronix TLA7xx logic analyzer modules, there is a soldered down Dallas NVRAM module. When the battery fails, the upgrade options and calibration data is lost. No big deal, just a bit of a hassle to redo the upgrade options and the self-calibration on every power on. It's been a while since I looked at any TLA7xx logic analyzer modules. I know I had one with a dead Dallas NVRAM module. No idea if I have more dead one now since the last time I looked. I didn't bother trying to desolder and replace the dead NVRAM module.

That is less of a complete failure than that which sometimes happens with the newer Agilent logic analyzer modules. It might be something that is more common with the 16700/16900-series logic analyzer modules than the 16500-series logic analyzer modules. My guess is that a 16555A/D, 16556A/D, 16557D module that is still working today is likely to keep working for quite a while.

[mbalmer]

In the Tektronix TLA7xx logic analyzer modules, there is a soldered down Dallas NVRAM module. When the battery fails, the upgrade options and calibration data is lost. No big deal, just a bit of a hassle to redo the upgrade options and the self-calibration on every power on. It's been a while since I looked at any TLA7xx logic analyzer modules. I know I had one with a dead Dallas NVRAM module. No idea if I have more dead one now since the last time I looked. I didn't bother trying to desolder and replace the dead NVRAM module.

As I understand it, these NVRAM modules are also how one essentially unlocks the upgrades on the thing (at least, on the 7AA4 modules), so it might be worth it for that alone.

That is less of a complete failure than that which sometimes happens with the newer Agilent logic analyzer modules. It might be something that is more common with the 16700/16900-series logic analyzer modules than the 16500-series logic analyzer modules. My guess is that a 16555A/D, 16556A/D, 16557D module that is still working today is likely to keep working for quite a while.

I have another 16717A coming in the next couple of days, as well as a 16557D with cables coming, so I will at least give those two boards (along with some of the troubleshooting from the other thread) a shot before I decide to give up on the 16702B.

[mbalmer]

Mechatrommer already mention this but you can make your own adapter for the P6860. Someone was selling the adapters on ebay, (see attached pictures).
The other option is P6960 with 196-3494-01 adapter but you have to wait to get a good deal, (I paid $100US for both the probe and adapter but I had to wait).

You are in the US so don't just look at E-bay for logic analyzers. I am seeing auction sites way cheaper (under $1000) than E-bay for newer Tektronix logic analyzers, (TLA7012 and TLA6404 etc).  Someone bought a TLA6404 on an auction site for about $500 and was trying to sell it on E-bay for $5000, (he also posted it on this forum).

Be patient.

Where else are you looking? I only really know about eBay and a handful of e-waste folks that happen to deal in test equipment to look at.

[Halberd]

My 16902A did not fail but to make it run a little faster, I replaced it with a new HDD and completely re-installed it and updated the LA application to the last release for use.

If you have the installation CD(with WindowsXP Key code) and only the HDD is broken, recovery is rather easy.

I think I'm throwing in the towel on the 16902 simply because of the cost of the 90-pin flying lead sets (between $400 and $2,000 in varying states of completness?!?! ), so as much as I'd like a module like that, it's a bit out of reach.
 in terms of watching data lines.

Indeed, 90-pin flying leads are very expensive. I have never seen cheap used ones and I can't afford them either.
However, Samrtec/Mictor connector or soft-touch connectorless type cables can be found on eBay for less money.
I bought mine from the US on eBay. And,Samrtec/Mictor was purchased from DigiKey.
As others have written, we recommend making your own flying leads, etc.

And 169xx modules are for 169xx frames only, but some 167xx modules can be used with 169xx frames.

[mbalmer]

I received a sixth and seventh 16717A board today. I plugged what we'll call Board F into the mainframe as the only board installed, and immediately received an error upon bootup that said that the module failed its' high-speed system clock test, and it claimed that the frame may need service.

However, the board passes all tests with x modtests from within pv.

I then re-ran all tests by setting d=9 (but not r=9).

As it ran the test, once it reached the vramCellTest, it flooded the screen with information, mostly clock numbers and hexadecimal codes which I'm guessing relate to specific VRAM cells, the data sent and the data read back. It sat there counting down clock codes from over 2,000,000 for a good solid 30 minutes before it moved on to the next test. After letting it run, all the tests passed on debug level 9.

I pulled Board F out, and replaced it with Board G. The frame powered up and got to the Workspace system without throwing any errors, so I logged into it via telnet and then ran a suite of module tests through pv.

Sure enough, it fails three tests: cmpTest, calTest, and zoomAcqTest.

This one fails cmpTest in an unusual way, however:

 

Code: [Select]

  Check POD1 Thresholds:
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk No Act.
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk No Act.
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk Levels
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk Levels
    Slot E, Chip 9: . ........ ........  B BBBBBBBB BBBBBBBB  Cal Clk Activity
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk Activity
  Check POD2 Thresholds:
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk No Act.
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk No Act.
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk Levels
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk Levels
    Slot E, Chip 9: B BBBBBBBB BBBBBBBB  . ........ ........  Cal Clk Activity
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk Activity
  Check POD3 Thresholds:
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk No Act.
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk No Act.
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk Levels
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk Levels
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk Activity
    Slot E, Chip 8: . ........ ........  B BBBBBBBB BBBBBBBB  Cal Clk Activity
  Check POD4 Thresholds:
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk No Act.
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk No Act.
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk Levels
    Slot E, Chip 8: . ........ ........  . ........ ........  Cal Clk Levels
    Slot E, Chip 9: . ........ ........  . ........ ........  Cal Clk Activity
    Slot E, Chip 8: B BBBBBBBB BBBBBBBB  . ........ ........  Cal Clk Activity
> Slot E: Comparator Test Failed!

I'm about ready to give up on this boat anchor. This is potentially only one out of seven boards I've received that has successfully passed all of its tests, and even then, the mainframe doesn't fully like Board F since it throws a boot-time error about the system high-speed clock.

[RomDump]

Where else are you looking? I only really know about eBay and a handful of e-waste folks that happen to deal in test equipment to look at.

I don't know any auction sites in the US, (I am in Canada) but the guy bought the TLA6402 from the Auction Mill.

BMI Surplus has a TLA715 with cables (no hard drive) for $900US.

I think a better option for hobbyist if they are going with Tektronix and want it working out of the box would be the TLA5204/B series. Yes I know about the motherboard capacitor issues. The main problem is the price. I have never seen a working one under $1000.

As others have stated the TLA715 has to be used as a controller (being remote control). Whereas the TLA5204/B  spec wise has a better processor and is still usable as a standalone unit.

I have a TLA715 btw and I haven't actually used a TLA5000/B so this is just a thought I have. YMMV.

[mbalmer]

I don't know any auction sites in the US, (I am in Canada) but the guy bought the TLA6402 from the Auction Mill.

I'll keep that in mind. I know of a few local auction places, but especially where I'm at, test gear is an exceptional rarity. I'm much more likely to find power tools, tin signs, and hubcaps on auction sites. 

I think a better option for hobbyist if they are going with Tektronix and want it working out of the box would be the TLA5204/B series. Yes I know about the motherboard capacitor issues. The main problem is the price. I have never seen a working one under $1000.

$1k is out-of-range for me, so it's looking like the TLA 715.

I'm still going to give the 16702B some love (especially because I have a working 500MHz scope module for it) but I am thoroughly frustrated with the failing boards on this thing. It might see some service when I see the 16557D that I had ordered, but for right now, the thing is basically dead in the water for me.

As others have stated the TLA715 has to be used as a controller (being remote control). Whereas the TLA5204/B  spec wise has a better processor and is still usable as a standalone unit.

As I understood it, the TLA has front panel controls, as well as a keyboard and mouse port, and didn't explicitly have to be controlled over a network. Even so, I intended to hook it to my network, so that shouldn't be much of an issue.

[mbalmer]

we try to make our own flying lead.. if no other cheaper option... https://www.eevblog.com/forum/testgear/tla7aa4-p6860-probe-artwork/?topicscreen if you need gerber file for the one i've created, you can ask anytime, i will search where i've put it. ymmv.

I'm looking at that thread now, it looks like you can just break out the signals to 0.1" header. I wonder if it could be adapted to work with all of these 40-pin HP flying lead sets I've come into possession of.

[nctnico]

Where else are you looking? I only really know about eBay and a handful of e-waste folks that happen to deal in test equipment to look at.

As others have stated the TLA715 has to be used as a controller (being remote control). Whereas the TLA5204/B  spec wise has a better processor and is still usable as a standalone unit.

IMHO the TLA715 is a much better buy because you can swap (upgrade) the modules. I do have to say though that whatever you run the sofware on, it is going to be slow so having a 'fast' processor in the logic analyser itself or your remote control PC isn't going to help. For some reason Tektronix wrote the software in a very clumsy way that doesn't fully utilise the processor at all. An SSD is the most worthwhile performance update.

[mbalmer]

IMHO the TLA715 is a much better buy because you can swap (upgrade) the modules. I do have to say though that whatever you run the software on, it is going to be slow so having a 'fast' processor in the logic analyser itself or your remote control PC isn't going to help. For some reason Tektronix wrote the software in a very clumsy way that doesn't fully utilise the processor at all. An SSD is the most worthwhile performance update.

Fair enough -- as I mentioned, I think at this point, the HP is pretty much out of the running simply due to how many failures I've had with it. The 16702B has the scope board, one lonely working LA module (with the runners removed cleanly, so there's no hope of them corroding in the future) and six more that are in various states of failure. If I can get two or even three of the boards working, then I might turn around and re-sell the LA, but for right now, it's an interesting repair project. The TLA will be the actual analyzer I use when it gets here -- once I can get the probe adapter boards made.

[RomDump]

The TLA will be the actual analyzer I use when it gets here -- once I can get the probe adapter boards made.

btw: With the TLA715 you have options instead of making the probe adapter board.

You can buy a TLA7P4 module and P6417/P6418 probes.

Most people just bought the TLA7AA4 and P6860 probes because it was widely available.

[nctnico]

I strongly recommend going for the P6417 as these have better contacts compared to the P6418. If you go that route...

The advantage of the TLA7AA4 module besides even more memory and higher samplerates are the 4 analog outputs that output any of the input signals. It is super handy to be able to connect an oscilloscope and use the logic analyser as an analog mux / buffer to look at various signals. That way you have a mixed signal analysis tool. IIRC the analog bandwidth is >1 GHz.

[mbalmer]

btw: With the TLA715 you have options instead of making the probe adapter board.

You can buy a TLA7P4 module and P6417/P6418 probes.

Most people just bought the TLA7AA4 and P6860 probes because it was widely available.

Yeah, that's basically what I did. The 715 is going to come with a 7AA4 installed in it, and I could find P6860s for about $15 each -- and also because supposedly, the 7AA4s are up-hackable in a rather dramatic fashion.

Now my goal is to just get my hands on either the schematic for the probe adapters, or the footprint for the probe heads, so I can instead design an adapter to an HP flying lead set instead -- since I've got something like 12 of them now.

I strongly recommend going for the P6417 as these have better contacts compared to the P6418. If you go that route...

I went the P6860 route.

The advantage of the TLA7AA4 module besides even more memory and higher samplerates are the 4 analog outputs that output any of the input signals. It is super handy to be able to connect an oscilloscope and use the logic analyser as an analog mux / buffer to look at various signals. That way you have a mixed signal analysis tool. IIRC the analog bandwidth is >1 GHz.

Doesn't that functionality require a compatible scope? I remember reading that there were certain scopes that were "supported" but I don't own one (I have a TDS 460, which isn't on their list). I'm guessing this is a BNC output on the LA that goes to an input on the scope.

[nctnico]

There is some software / hardware tool to support cross-triggering between Tektronix scopes and their logic analysers. But I don't really see the need for that. You can use the trigger input / output on the logic analyser just fine to make it work together with an oscilloscope from any brand. The analog outputs on the TLA7AA4 module are just analog outputs; it doesn't matter what you connect it to. IIRC even the gain is adjustable.

The footprint for the probe heads is in the P6860 user manual

[alm]

In my opinion the main advantage of integration between a scope and a logic analyzer is to see both signals simultaneously on the same time base. The HP/Agilent logic analyzers with their contemporary scopes had a feature where the scope and analyzer's timebases were synchronized so time relationships between the digital and analog signals would be maintained, and you could for example see the relationship between a glitch in an analog signal on the scope and a specific pattern on the digital bus. Before that some analyzers had optional internal DSO channels that would sample on the same timebase as the digital channels, but the scopes were pretty anemic in terms of memory depth.

I would imagine the Tektronix tool did something similar, but it will generally only be supported with scopes from the same manufacturer and time frame.

[RomDump]

Doesn't that functionality require a compatible scope? I remember reading that there were certain scopes that were "supported" but I don't own one (I have a TDS 460, which isn't on their list). I'm guessing this is a BNC output on the LA that goes to an input on the scope.

There is some software / hardware tool to support cross-triggering between Tektronix scopes and their logic analysers. But I don't really see the need for that.

In my opinion the main advantage of integration between a scope and a logic analyzer is to see both signals simultaneously on the same time base.

I would imagine the Tektronix tool did something similar, but it will generally only be supported with scopes from the same manufacturer and time frame.

The product Tektronix called Iview, (I beleive it is already built in to the TLA 4.3 and up software). Basically with a compatible Tektronix scope, a NI GPIB-USB-B(or HS) cable and some BNC cables you can see a correlation between analog signal and digital signals. As ALM mentioned, one use would be to see glitches.

You don't need a TLA7AA4 with analog inputs but it is helpful as you can automatically route the digital line you want to see.
With the older modules you had to do double probing (one probe from the oscilloscope and one digital line from the logic analyzer) which would introduce additional signal integrity issues.

[mbalmer]

So after playing around with the TLA, the one thing I've noticed is that since it runs Win2K out of the box, it doesn't have remote desktop functionality built in. Everything I've read says that an upgrade to Windows XP is required to do that.

However, I'm running into a problem. The BIOS version is 1.00.00, and supposedly, there's a 1.00.02 version that it may or may not need to be updated to to make it possible to upgrade it to XP. My issue there is that there's no way to use a floppy to boot the system since it doesn't seem to like floppies formatted using Windows 98 -- and Win2K can't create boot floppies that aren't intended as a means to eventually install Win2K. I haven't tried formatting the disk from a running XP machine, but that's next on my list.

My question is, is there a disk image that I can boot from that includes the BIOS file? TiN seems to have the files on the xdevs website, but even he mentions that you have to make a bootable floppy to use them.

I've tried using a Windows XP install disk directly, and the system appears to hang at the "Setup is starting Windows" segment in text mode (when it changes from an 80x25 to an 80x30(?) screen). My guess is that the installer is still running, but the video system doesn't know how to handle the oddball text mode. Has anyone else had that happen?

In the probes department, I'm still trying to figure out an answer. I've got four sets of probes now, and new elastomers on their way, so hopefully I'll have something workable here soon, but it doesn't look like anyone has a KiCad library for the probe footprint just yet.

The help all of you have given me so far has been invaluable and I'm overall much happier with the Tek device, assuming I can get the probes and remote control thing sorted out.

[nctnico]

You don't need remote desktop. Install the logic analyser application on your regular PC and start the remote control server on the logic analyser. Remote control isn't remote desktop but SCPI / GPIB like over LAN. Don't upgrade the LA to XP because the hardware drivers won't work with XP.

[RomDump]

Don't upgrade the LA to XP because the hardware drivers won't work with XP.

What hardware drivers are specifically missing? First time I am hearing of this.

[nctnico]

Don't upgrade the LA to XP because the hardware drivers won't work with XP.

What hardware drivers are specifically missing? First time I am hearing of this.

I start to think I made a mistake. From my old posts it seems the TLA715 can run Windows XP. I started my TLA715 (for the first time in 3 years or so) and it runs Windows XP indeed.

In my old post I also warned about the removable drive bay; these are prone to problem so mount the hard drive internally.

[mbalmer]

I start to think I made a mistake. From my old posts it seems the TLA715 can run Windows XP. I started my TLA715 (for the first time in 3 years or so) and it runs Windows XP indeed.

In my old post I also warned about the removable drive bay; these are prone to problem so mount the hard drive internally.

I've heard about the removable drive bay. It's functional on my system, so I won't necessarily stop using it, however, I also have an mSATA SSD and an adapter to 2.5" 44-pin IDE that I intend to put XP on along with updated versions of the TLA software as I've read elsewhere (supposedly, the drivers for the modules are included with the TLA software, and some places say version 5.1 works with it, others say 5.6 and even version 6, but I've also been told that versions above 5.1 need firmware updates to the modules to make them work). I'll hopefully end up mounting the mSATA drive internally, but I want to get past the installation of the software first.

If something doesn't work, my intent is to keep the removable hard drive bay on hand so that if something goes awry, I can simply put the old drive back in it and it should be fine.