Is Lecroy WaveSurfer 64Xs upgradable??

[nathankwan]

Hi all, I came across this used wavesurfer 64Xs and found it very strange, It's got "64Xs 600MHz 2.5GS/s" written on the bezel of the screen, but in the status menu it shows the model is "WS104MXs". The seller is selling this scope at around $1000.

I got confused since I took a glance at the official datasheet and didn't find anywhere mentioning the bandwidth and sample rate is upgradable, I am beginning to think whether this scope is hacked, or (at least) the front panel is replaced.

I read another thread on eevblog and a dude said all these years he didn't saw a single lecroy that has its bandwidth upgraded, which brought me thinking maybe the scope isn't what it looks to be.

Can anyone share some opinions? Thanks!

[coromonadalix]

simply put  i would not touch it 

to check the real bandwith, you need other equipement .... 

it could be hacked and real too but nothing is out in the field ??  and you need the probes  for the hacked BW  not the originals,  wich is more $$$

there is a few threads here, but nothing about SV manuals or hacks as far as i know

EDIT  from a lower response thread   there is a python script ...

[alm]

to check the real bandwith, you need other equipement .... 

Something like this?

it could be hacked and real too but nothing is out in the field ??  and you need the probes  for the hacked BW  not the originals,  wich is more $$$

I haven't heard about hacking these either. At least on earlier scopes, the model number could be changed but the bandwidth was limited by hardware. So it's possible it's actually a 600 MHz scope. Earlier scopes like the WavePro 7000 had very fragile front panels where having them replaced would make sense. Not sure about this series. $1000 is cheap for this scope, I think. Possibly suspiciously so. I'd seriously consider it if it were local and I could test it with some signals, or maybe if it was advertised as fully working on eBay and return shipping would be affordable.

You absolutely don't need probes because of the increased bandwidth. For staters, good luck finding a 1 GHz passive probe high-impedance probe. A 100 MHz or 500 MHz passive probe will work just fine with it (as well as passive probes work at higher frequencies). Same with active probes. A 15 MHz high-voltage differential probe or a 500 MHz low voltage differential probe will work fine on a 1 GHz scope. It's just that if you want to use the full bandwidth you need more expensive probes, or a direct 50 Ohm connection. But there's very little downside about having a scope with a wider bandwidth than necessary other than the higher price. Maybe more noise, but bandwith limit can take care of that.

[lollokara]

Hi i do have the exact model you are referring to, opened it many times for repasting/changing the damn hard drive that gets busted in a 80C internal temp instrument. My acquisition board clearly states the frequency and sampling speed (like written on the board not via software) so what I’m saying is that this instrument do not offer “bandwidth” upgrades like rigol or others but just decoding packs or other. My advice is to stay away, probably but this is just a speculation at this point, someone replaced the acquisition board inside with another model probably faulty. Problem is that the cal data is scope dependant and stored in the CPU board. A front end board with a different acquisition board can cause issues in the cal data.

Too foggy for 1000 bucks…

[nathankwan]

Thanks for all the replies!

I contacted the seller, and as he implied(not admitted explicitly though, but I really suspect it), they somehow got the internal maintainance software tool for lecroy, that allows them to modify software options freely on their will. My guess is that since some models of lecroy scopes are manufactured in China, it could be possible that they are using some sort of leaked factory production tool that can do the job.

Based on this guess, I believe they just blindly tackled with models and software options, it's still a 600MHz scope with 2.5GS/s sampling on each channel, since that is determined by hardware. But that wouldn't explain why it shows 5GS/s sampling (in the timebase window on the right bottom corner) when all 4 channels are on. According to the datasheet it's not possible for any of the Xs series scopes, but only the true 104MXs.

I was thinking that all the displayed parameters, like models, add-ons, can be tricked by the tools the seller used, but the actual sample rate too?

Anyway I won't touch this. I thought $1000 is pretty good for a 64Xs(the seller promises a full return-and-refund if the scope isn't working as he claimed to be), but knowing they are capable to do all these blind hackings really holds me back.

Thanks again for all the opinions.

[nathankwan]

to check the real bandwith, you need other equipement .... 

Something like this?

it could be hacked and real too but nothing is out in the field ??  and you need the probes  for the hacked BW  not the originals,  wich is more $$$

I haven't heard about hacking these either. At least on earlier scopes, the model number could be changed but the bandwidth was limited by hardware. So it's possible it's actually a 600 MHz scope. Earlier scopes like the WavePro 7000 had very fragile front panels where having them replaced would make sense. Not sure about this series. $1000 is cheap for this scope, I think. Possibly suspiciously so. I'd seriously consider it if it were local and I could test it with some signals, or maybe if it was advertised as fully working on eBay and return shipping would be affordable.

You absolutely don't need probes because of the increased bandwidth. For staters, good luck finding a 1 GHz passive probe high-impedance probe. A 100 MHz or 500 MHz passive probe will work just fine with it (as well as passive probes work at higher frequencies). Same with active probes. A 15 MHz high-voltage differential probe or a 500 MHz low voltage differential probe will work fine on a 1 GHz scope. It's just that if you want to use the full bandwidth you need more expensive probes, or a direct 50 Ohm connection. But there's very little downside about having a scope with a wider bandwidth than necessary other than the higher price. Maybe more noise, but bandwith limit can take care of that.

I have a pair of old tektronix P6202 active probes that a friend of mine in the university gave me, saying "no one in their lab knows what the hack these are for and he was asked to throw them away". I have a used TDS784C and was wondering if there is any possiblility that those old probes can be used on that scope.

[alm]

I contacted the seller, and as he implied(not admitted explicitly though, but I really suspect it), they somehow got the internal maintainance software tool for lecroy, that allows them to modify software options freely on their will. My guess is that since some models of lecroy scopes are manufactured in China, it could be possible that they are using some sort of leaked factory production tool that can do the job.

Are you sure they are not just using this tool? The knowledge on how to modify software options has been out for a while.

Based on this guess, I believe they just blindly tackled with models and software options, it's still a 600MHz scope with 2.5GS/s sampling on each channel, since that is determined by hardware. But that wouldn't explain why it shows 5GS/s sampling (in the timebase window on the right bottom corner) when all 4 channels are on. According to the datasheet it's not possible for any of the Xs series scopes, but only the true 104MXs.

There may be a hardware bandwidth limiter, but not necessary be a sample rate limiter.

I have a pair of old tektronix P6202 active probes that a friend of mine in the university gave me, saying "no one in their lab knows what the hack these are for and he was asked to throw them away". I have a used TDS784C and was wondering if there is any possiblility that those old probes can be used on that scope.

Yes, that will work fine. Active probes like this, unless you are getting in the really fancy multi-GHz bandwidth probes with DSP correction, output a very standard signal that will work with pretty much any 50 Ohm input. The only caveat is that they need power and sometimes control signals like offset. There are adapters and external power supplies (e.g. Tek 1101/1101A) for that purpose, though these are somewhat rare and expensive. But I'm pretty sure the the P6202 (though not P6202A) just has a plain power brick, and should work on any Tek, Keysight, Lecroy etc scope with a 50 Ohm BNC input. For the P6202A you would need someting like a Tek 1101/1101A to power it.

[coromonadalix]

oooooh  ok    i forgot this thread

and yes the seller could be an eevblog member here  loll

[tv84]

Are you sure they are not just using this tool? The knowledge on how to modify software options has been out for a while.

This only works for old FW versions. For current MAUI, it's useless.

[nathankwan]

I'll give it a try later, I believe those probes can do offset setting right on the probe itself, having an offset adjustment knob on the bulky plug... They've been in the blue box for too long and smells really funny so I didn't took a closer look when I first got them.

[nathankwan]

My acquisition board clearly states the frequency and sampling speed (like written on the board not via software) so what I’m saying is that this instrument do not offer “bandwidth” upgrades like rigol or others but just decoding packs or other.

Yesterday out of curiosity I talked to the seller again and had him shown me a short video of the sample dots(not vectors) at 1ns/div with all 4 channels on, and suprisingly all 4 channels have 5 sample points per division, suggesting this IS a simutaneous 5GS/s sampling scope (or acqusition card). Those dots didn't seem to be the result of some interpolation (randomly hopping).

according to the datasheet, only WS104MXs has 5GS/s on all channels, could it be someone switched out the 104MXs acquisition board and pluged it in the 64Xs? Is that even possible?

[lollokara]

No idea really...

[nathankwan]

I met some guy at yahoo groups and learnt that (m)xs/i series acq board all have the same hardware design (therefore capability), so 64xs should has the same acq board as 104mxs. I believe the seller has hacked the eeprom to let xstream software believe it's operating on a 104mxs, therefore unlocking some of the sampling capabilities.
However 104mxs can do interleaved sampling on less than 2 channels to achieve 10GSps, which I persume is coordinated by the fpga in between the adcs, whose configuration cannot be hacked, so the machine thinks it's a 104mxs, but not all features can be unlocked.

I begun to think 1kusd is worth a try, however when I got back, the scope is already sold...

[darkstar49]

there's no black & white answer...

The Xs has had 5 generations (Xs without LBUS, Xs with LBUS, Xs-A, Xs-B with PS/2 ports, MXs-B without PS/2 ports).
To my knowledge, Xs and Xi shared the same h/w platform.

I think 2.5GS/s for a 64 models only existed for models without LBUS (serial < LCRY0310xxxxxx). 104 models had the same acquisition h/w (as a 64), but... the FE board was physically different (a bit wider, leading the power button to become rectangular, and not square), and attached differently, so the acquisition board for the 104 (and also 204 for the Xi) was physically different from the acquisition board on the 24, 44 and 64 models.

edit: my bad, not really familiar with the Xs, it was indeed 4 x 2.5GS/s, which could be interleaved to 5GS/s on the 104Xs. No clue whether this was a software-based limitation or if the ADCs were indeed different from those on the Xi series ?

So, to come back to the original question: no, the 64Xs is NOT upgradeable (as for the bandwidth).