Suggestions for a good second-hand LA?

[mbalmer]

I recently purchased an HP/Agilent 16702B without knowing about the (apparently) infamous corrosion issue due to the plastic runners used on the bottoms of the module boards. I went back and forth with the equipment company that sold it (it was sold as fully functional and non-DOA) exchanging boards with them -- every single one they sent me had corrosion issues that were clearly visible or were invisibly damaged to the point that the boards threw errors.

They were tremendously gracious with me on this, and I don't fault them for not knowing.

The mainframe was sold originally with a 16534A 2Gs/s, 500MHz two-channel scope board and two 16717A timing and state modules. Upon first boot, I immediately ran the self-test suite. The mainframe passed, and the scope passed, but one of the two 16717s failed its VRAM tests. The other board passed -- for a little while. It started throwing Comparators and ZoomChipSelTest errors -- about which I've posted in another thread in the (vain?) hope of trying to revive it.

The company sent me additional boards in the hope that another one would pass, but to no avail -- and now I have a total of five of these boards, none of which pass their self-tests.

That said, I'm looking at other possibilities for a good second-hand LA.

I've got an opportunity to get my hands on an Agilent 16902A that has a (potentially) faulty HDD -- the person selling it said that they can't test the logic analyzer module (a 16950B) because they can't get the system to start. Apparently, it blue-screens during the boot process. If that is indeed the case, that the thing just needs an OS reinstallation, would a unit like this be something more viable?

If not, are there any other suggestions for something that doesn't cost me several thousand dollars?

[BillyO]

If you have room and want a NASA/Space-X/LLNL grade LA what about the HP 3314A?  I have one older than my 30+ YO son and it works flawlessly.

Looks as cool as f'k on the bench too.

[mbalmer]

A 3314A? Isn't that a function gen?

[BillyO]

My bad.  Wrong awesome device.

This is what I was aiming at.  The probes plug in the back, and IIRC you can have 32 of them.



HP 1651A.

Yeah, not the gorgeous SG.

[BillyO]

A 3314A? Isn't that a function gen?

It is.  I made a bad all over the forum...

[mbalmer]

Which cables are the ones compatible with it? The only ones I'm seeing that I'm sure have them are absurdly expensive in the shipping department -- since they appear to be coming from overseas (to the US).

I see a part number in an old HP Manual of 01650-61607, but a search for that part number turns up nothing on eBay. I've already got a couple of cables that go with the 16702B, and they look similar, but it's unclear whether the cables are actually the same in terms of how they connect to the back. My guess is that they aren't, but I figured it couldn't hurt to ask.

[gslick]

I've got an opportunity to get my hands on an Agilent 16902A that has a (potentially) faulty HDD -- the person selling it said that they can't test the logic analyzer module (a 16950B) because they can't get the system to start. Apparently, it blue-screens during the boot process. If that is indeed the case, that the thing just needs an OS reinstallation, would a unit like this be something more viable?

If you want a logic analyzer with flying lead probe connections, you don't want a 16950B logic analyzer module. The 16950B uses the 90-pin POD connectors. You would pay more for a single E5382A 90-pin POD breakout lead set than you would for the 16902A and the 16950B.

If your 16702B is fully functional, one of the lower cost options to get going with it might be to pick up some 16555A/D or 16557D logic analyzer modules if you can get them at a reasonable price, with the cables included. The 16717A logic analyzer module cables are not compatible with the 16555A/D or 16557D logic analyzer modules. (They both use the same 40-pin connectors on the POD end of the cables).

If you could get by with only 4K of sample depth, you might be able to pick up some 16550A logic analyzer modules real cheap (i.e. not much more than the cost of shipping) to use with the 16702B.

[mbalmer]

You would pay more for a single E5382A 90-pin POD breakout lead set than you would for the 16902A and the 16950B.

That's the odd thing...the 16702B came with one E5382A in its pouch, inexplicably. Knowing that, does that change anything?

[gslick]

You would pay more for a single E5382A 90-pin POD breakout lead set than you would for the 16902A and the 16950B.

That's the odd thing...the 16702B came with one E5382A in its pouch, inexplicably. Knowing that, does that change anything?

Well that is some good luck, although a single E5382A flying lead set would only give you 17 logic analyzer channels. If you need more than 17 channels, then you would be back to paying a lot for another E5382A.

Also, if a E5382A flying lead set gets a broken lead, the broken lead can't be replaced. On the original 40-pin POD flying lead sets, the leads can be individually removed and replaced. The cost of the 40-pin POD flying lead sets is reasonable enough that they can somewhat considered to be consumable items that can be replaced as they experience wear and tear.

[mbalmer]

I should also mention that I’m not wedded to HP, either, as I have a Tek scope and power supply. I’ve seen TLA 714s that don’t look super expensive, but I’m unfamiliar with them or what’s considered “standard” for them.

[BillyO]

The cables are the 16550-61601.  You will also need a pair of 01650-61608 pods to go with it.  When I got mine, the cables were pretty cheap IIRC.  The cable and 2 pods (32 total connections) came to less than $100.  You can plug 3 of these sets in if you have the need and expand to 96 data inputs.

Update:  Sorry, this for the 1661 (my model)  I think you are right, the cable for the 1651 is the 01550-61607.  I wonder what the difference is.  HP/Agilent are famous for assigning different part numbers to identical parts for use with different equipment.  I guess you sell more accessories that way.

[nctnico]

I suggest to look at the Tektronix TLA700 series logic analysers. IIRC the TLA715 is affordable and not super old. Probes and modules can be found very cheap (and you can uphack the modules because they are software limited).

[mbalmer]

Tell me more about the Tektronix TLA 715. I’m not 100% sure that I am either ready or able to drop $2000 on one (because that’s about what they seem to be going for on eBay) but it’s worth some investigation. All of the units that I see on eBay that are less than $1000 are only the main frame portion, without any modules or cables.

I do see TLA 714s that are going for anywhere between $300 and $500, but I’m not sure whether that’s worth it.

It sounds like the most inexpensive option (at least from what I can make out) is to get an HP 16555D or 16557D, and get a set of cables to go with it. I’m having trouble finding either of those boards sold with their respective cables. Seems like people are parting things out.

However, don’t the 165XX series of boards also suffer from the same corrosion issues that appear to plague the 167XX series of boards too? I seem to remember some threads from before mentioning that both lines had issues with corrosion due to the plastic runners.

In terms of what I need, I am mostly working with older eight and 16-bit computer systems, game consoles, and the like. I have yet to venture into anything with a wider bit depth. While it’s conceivable that I could hop into something much deeper (as in trying to diagnose faults on a PlayStation 3) I’m not there yet, so my guess is that I don’t need anything more complicated than either 17 or 34 channels at one point. At this point, I certainly don’t need 8 pods worth of flying leads.

[Mechatrommer]

forum member TiN donated a TLA714 to me (with built in TLA7AA4) 4 years ago, i paid 100+ shipping. and then i buy accessories (incl SSD drive, touch screen, keyboard mouse and spare LCD ), overall including shipping costed me about a 1K, half of the price is TLA7E1 DSO Module 1GHz 5GSps out of pure lust i wouldnt recommend TLA714 (unless you have no other option) because the plastic covers all experience their natural disintegration. if you can get TLA715 its much nicer... i can see a mainframe for $477-600 (200 broken if want to take the risk fixing), a TLA7AA4 can be had $75, if you want cheaper TLA7L2/4 $28-50. and then P6860 34-Channel probes, last time i got deal 7 pieces for about $100+ including shipping but i cant see that anymore but there are seller still selling at $20-30 per piece. 4 piece should be a good start for 136 channels. so overall maybe you can get them working at $700. not really a cheap option anyway, but thats the cheapest we can get. how much channels and speed do you need? if only 8-16 channels, salae logic is much more modern, and there are clones. ymmv.

[nctnico]

$2k for a TLA715 is way too much. I'd start by lowballing at $250. See who bites. Many of the 'broken' ones simply miss the removable hard drive bay and thus won't boot. If the seller can show the display works with a boot error, all it takes is fitting an SSD in the internal bay and install the OS (Win2k). The removable hard drive bay is prone to poor contact anyway.

Next thing is the software: you can control the TLA700 series remotely buy running the software on your PC. It won't be any faster or slower compared to using the LA directly but having a bigger screen is way more comfortable. You'll need a mainframe with a network connection. You'll need a 10/100Mbit Cardbus (not PCI!) PCMCIA network adapter. IIRC my TLA715 even came with such an adapter.

[gslick]

It sounds like the most inexpensive option (at least from what I can make out) is to get an HP 16555D or 16557D, and get a set of cables to go with it. I’m having trouble finding either of those boards sold with their respective cables. Seems like people are parting things out.

If you already have a fully functional 16702B, maybe I could set you up with a 16555A analyzer module with cables (two cables, breaking out to four 16-data-channel + 1-clock-channel PODs), but no flying lead sets, for not much more than the cost of shipping within the US. I could verify that the 16555A analyzer module currently passes all self tests. The 16555A is the 1M-sample version, the 16555D is the 2M-sample version. I have more 16555A logic analyzer modules than I will ever use at this point.

[mbalmer]

$2k for a TLA715 is way too much. I'd start by lowballing at $250. See who bites. Many of the 'broken' ones simply miss the removable hard drive bay and thus won't boot. If the seller can show the display works with a boot error, all it takes is fitting an SSD in the internal bay and install the OS (Win2k). The removable hard drive bay is prone to poor contact anyway.

Next thing is the software: you can control the TLA700 series remotely buy running the software on your PC. It won't be any faster or slower compared to using the LA directly but having a bigger screen is way more comfortable. You'll need a mainframe with a network connection. You'll need a 10/100Mbit Cardbus (not PCI!) PCMCIA network adapter. IIRC my TLA715 even came with such an adapter.

The mainframe options on eBay right now are pretty sparse. The ones that are sub-$300 are all very clearly not working or don't have an indication in the listing as to whether the system actually boots. I've messaged one seller about one that might be a candidate (it says "tested to power on" and the shots just show a backlit black screen). One mentions that it doesn't complete the boot process using WinXP instead of Win2K, which makes me think that it might be a viable candidate.

It also sounds like the LA modules for the Tek versions are generally less expensive for just as much capability -- it's the mainframes themselves that are the expensive portions.

If you already have a fully functional 16702B, maybe I could set you up with a 16555A analyzer module with cables (two cables, breaking out to four 16-data-channel + 1-clock-channel PODs), but no flying lead sets, for not much more than the cost of shipping within the US. I could verify that the 16555A analyzer module currently passes all self tests. The 16555A is the 1M-sample version, the 16555D is the 2M-sample version. I have more 16555A logic analyzer modules than I will ever use at this point.

I may just take you up on that, depending on how my search for a working 16717A plays out in the next few days. I've got one more replacement module coming, and if that doesn't work, I've found two 16557D boards that I might spring for, but I'm still REALLY leery of the corrosion thing, since I've been burned by five straight boards.

[gslick]

The mainframe options on eBay right now are pretty sparse. The ones that are sub-$300 are all very clearly not working or don't have an indication in the listing as to whether the system actually boots. I've messaged one seller about one that might be a candidate (it says "tested to power on" and the shots just show a backlit black screen). One mentions that it doesn't complete the boot process using WinXP instead of Win2K, which makes me think that it might be a viable candidate.

It also sounds like the LA modules for the Tek versions are generally less expensive for just as much capability -- it's the mainframes themselves that are the expensive portions.

If you wanted to go the Tektronix route, one option is a TLA721 mainframe. Those can sometimes be found for less than a TLA715 mainframe, even with the more expensive shipping for a TLA721 mainframe. Of course the very large downside to a TLA721 mainframe is the very large size. If you don't have a lot of open bench space, a TLA721 mainframe would not be a great option.

Where are you located? I have a couple of Tektronix full-sized VXI mainframe logic analyzer chassis that I should get rid of cheaply, but they are not something that I have any interest in trying to ship.

[Halberd]

I own and use both the 16702B and 16902A mentioned in the topic, as well as the 1672G.

I can't recommend anything since you didn't say what specs and features you need and what you use them for, but I can make a few comments.

I've got an opportunity to get my hands on an Agilent 16902A that has a (potentially) faulty HDD -- the person selling it said that they can't test the logic analyzer module (a 16950B) because they can't get the system to start. Apparently, it blue-screens during the boot process. If that is indeed the case, that the thing just needs an OS reinstallation, would a unit like this be something more viable?

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 recently purchased an HP/Agilent 16702B without knowing about the (apparently) infamous corrosion issue due to the plastic runners used on the bottoms of the module boards.

I have yet to obtain a module that does not work properly due to this problem, but I think this problem is rather an easy one to fix. I think this problem is rather easy to repair, since it can be determined to some extent by visual inspection and a tester.

I usually use the lowest spec 1672G for hobby use. Because it takes about 20 seconds from power on to use.
The 16702B should take about 4+ minutes and the 16902A about 2 minutes or less.
I bought a defective one, completely disassembled it, maintained it and used it, and the total cost of the three units(with some modules) was less than $1000.

[mbalmer]

If you wanted to go the Tektronix route, one option is a TLA721 mainframe. Those can sometimes be found for less than a TLA715 mainframe, even with the more expensive shipping for a TLA721 mainframe. Of course the very large downside to a TLA721 mainframe is the very large size. If you don't have a lot of open bench space, a TLA721 mainframe would not be a great option.

Where are you located? I have a couple of Tektronix full-sized VXI mainframe logic analyzer chassis that I should get rid of cheaply, but they are not something that I have any interest in trying to ship.

Joplin, MO. I am potentially willing to drive to pick up a unit, but it might have to wait until I get through some more of marching season (I'm a band director by profession).

I own and use both the 16702B and 16902A mentioned in the topic, as well as the 1672G.

I can't recommend anything since you didn't say what specs and features you need and what you use them for, but I can make a few comments.

Most of what I'm doing is diagnosing issues with 8-bit and 16-bit systems, and looking on the data/address buses of those systems along with serial and parallel bus spying. While I haven't done a larger bit depth system yet, there are some possibilities that I might later, so having the additional bandwidth to look will be helpful.

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.

I have yet to obtain a module that does not work properly due to this problem, but I think this problem is rather an easy one to fix. I think this problem is rather easy to repair, since it can be determined to some extent by visual inspection and a tester.

Seriously?! Somehow, I've had a string of five of them all in various states of disrepair. Two of them outright say the module has failed upon boot, the other three all throw errors related either to the comparators or the VRAM. I'm trying to see if I can revive some of them, but considering that my experience with these boards is very limited, I am struggling to perform tests and then dig out issues.

I usually use the lowest spec 1672G for hobby use. Because it takes about 20 seconds from power on to use.
The 16702B should take about 4+ minutes and the 16902A about 2 minutes or less.
I bought a defective one, completely disassembled it, maintained it and used it, and the total cost of the three units(with some modules) was less than $1000.

I don't mind the long power-up time -- what I do want, however, is something that can handle, at minimum, a 16-bit wide data bus (preferably a 32-bit bus or a 64-bit bus if I'm really lucky), along with associated address pins, chip selects, and such for diagnosing and watching data streams. Again, mainly for work on retro systems and consoles, but potentially as late as the PS3 or Dreamcast era in terms of watching data lines.

[mbalmer]

… and then P6860 34-Channel probes, last time i got deal 7 pieces for about $100+ including shipping but i cant see that anymore but there are seller still selling at $20-30 per piece. …

The only issue I can see with this is that the P6860 looks similar to the HP E5346A — in other words, it ends in a Mictor-style compression clip. I need flying leads. That looks like the P6810 — the actual flying lead sets look super affordable, but the cables are back-breakingly expensive (unless I’m missing something, the least expensive option is $670.

Any suggestions here?

[Mechatrommer]

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.

[RomDump]

The only issue I can see with this is that the P6860 looks similar to the HP E5346A — in other words, it ends in a Mictor-style compression clip. I need flying leads. That looks like the P6810 — the actual flying lead sets look super affordable, but the cables are back-breakingly expensive (unless I’m missing something, the least expensive option is $670.

Any suggestions here?

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 TLA6402 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.

[Mechatrommer]

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.

[nctnico]

The problem could also be in the mainframe (worn connector or someone gave it a treatment with contact spray).