Handheld Scope

[tristan]

Hi

I need another handheld scope.

I have a Fluke 123 which is slow (20MHz), basic and has no cursors but is really handy for a quick look and is pretty robust.

I also have a Fluke / Philips PM97 which is a bit quicker (50MHz) but has a pretty low sample rate.

When I really need it I have a picoscope 5204 strapped to the back of a tablet PC. This has 350MHz bandwidth, 1Gig sample rate and a huge 128M samples memory. This is brilliant and the deep memory is excellent but I always feel a bit nervous crouching on the roof a filthy military vehicle debugging a dodgy turret interface node clutching a fragile £2500 piece of equipment hoping it doesn't rain!

I am looking at a Tek THS730A which seems to be pretty good and is pretty cheap second hand. It has 200MHz bandwidth, 1Gig sample rate, isolated (floating) inputs which is really handy and a reasonable-ish 2500 sample memory per channel. It also seems pretty rugged and it can't be too bed if it's a Tek. It's also less than half the price of a fluke 196.

Does anybody have any experience of this scope or any suggestions for something else to look at? I do everything from uP design through to military / commercial vehicle electrics and factory automation so I need a fairly capable piece of kit.

Thanks

Tristan

[Simon]

does it have to be portable / tiny ? you'll get better values for money with a larger unit although I suppose you may not have mains power available

[tristan]

Yes it has to be handheld and battery powered and preferably pretty rugged - I have bench scopes and the Picoscope if I have somewhere to work and access to power. I have a peli case fitted with SLA batteries and an inverter for when I really need mains power but can't get it but it's not exactly convenient when access isn't easy.

Tristan

[Simon]

then be prepared to pay out ! not only are you looking at a sofisticated device you looking at a nich market, we all have bench scopes but few need a portable so the price per head for reasearch into that product is higher apart from the extra cost of small and more power efficient parts

[tristan]

I'm prepared to pay out - I'll probably end up getting a Fluke 196 or 199. However the Tek THS730A has a pretty good spec. and is available second hand for 20% of the cost of the Fluke. I'd be interested to hear if anyone has any experience of this model.

[Mark_O]

I'm prepared to pay out - I'll probably end up getting a Fluke 196 or 199. However the Tek THS730A has a pretty good spec. and is available second hand for 20% of the cost of the Fluke. I'd be interested to hear if anyone has any experience of this model.

Tristan,

I had one of these on loan for about a month, and had plenty of time to work with it.  Its specs are good, and so was usability.  I had no problems with it (mostly looking at digital circuits for glitches, and high-speed CAN bus traffic), and it had a good feature set and was rugged.  

My biggest complaints about it were relatively minor: the display had a somewhat narrow viewing angle, and I had to fidget with it for best visibility.  And the Ni-Cad battery was only rated for 2 hours, but I never got more than 90 minutes out of it.  I constantly felt like I needed to watch the time and conserve my battery power.

Unfortunately, I have no experience with the Fluke you mentioned, to be able to give you any comparative evaluation.  I do see that it has FFT, which the Tek lacks, and has NiMH battery, with 4 hour charge (rated).  Also a nifty strip-chart capability, that can log data for up to 3 weeks.

I'd say if you can get the Tek for 1/5 the price of the Fluke to go for it, unless the battery lifetime will be an issue for you.

- Mark

[Mark_O]

BTW,

I never looked into alternate battery packs for the Tek, since it was a loaner, but that may be something you might want to look into.  I have a vague recollection that the battery module was something like a D-cell cylinder in size.  If nothing else (longer capacity or NiMH options), another stock THS730A battery might be good to have on hand when the 1st one runs out on you.

- Mark

[tristan]

Thanks Mark, this is just the kind of information I wanted. I'm going to go ahead and order the THS730A - If it's not what I want I can always resell it and get the Fluke. Although based on what you have said it looks like it will be perfectly adequate.

Tristan

[qno]

Hi tristan,

I have a THS720 myself and i think it is perfect.
It has 2 isolated scope channels and a separate DMM also isolated.
The RS 232 is also isolated.

There are free tools available on the web ( screen dump logger FFT ) See the THS Fan site: http://warped.org/tek/
I find myself using it more and more, I also have a fluke 123.
The fluke is a bit more responsive on the key operation and the trend plotting is better than the graphical DMM of the Tek but the tek has many more options like cursor, waveform measurements and trigger options.

The battery can be made by yourself easily, I have build adapters myself to accomodate for 4 AA batteries, 4 Sub-C cells (the ones used in power tools), and also 4 C-type cells can be accommodated.
The C- cells have to be shrink- wrapped because these have only a few mm of room. I think the genuine Tek battery pack is also standard C cell.
The rest can be rolled in  cardboard to make the smaller battery pack fit. Battery life is about 1 hour with 1500 mAh cells. (that is the capacity my NiCd capacity meter tells me is in the C-cells) You can buy better cells.

Switch the THS off before changing the battery pack or else your calibration variables are destroyed.

It is easy to calibrate the Tek yourself. You just start the calibration procedure and apply the correct signals.
Maybe something for Dave to checkout?
I like this little scope/dmm even tough it is 15 years old.

[mikeselectricstuff]

I got the Owon 60MHz one a while ago.
Good points :
small size/weight, pretty good screen response speed.Useable without backlight to save power. Battery life seems OK.

Bad :
User interface is a complete dog's breakfast - very inconsistent and no evidence of being thought out. Volts/div works the wrong way round. I don't use it often enough to have got used to its quirks so find it irritating whenever I use it - would probably be OK for more regular use.
No pulse-width trigger or holdoff.
DMM could have been implemented rather better - too slow and the meter needle is a bit of a gimmick - a bagraph would be better. Would be nice to not have to take a fluke as well as the scope...
Side BNCs can be awkward - top would have been better.
 
The backlight on mine is flaky but this may be a 1-off, and it is useable without in good light - I'll probably replace  the CCFL with white LEDs when I can be bothered.

All in all I've yet to see anything better for what I use it for, but better firmware could make a huge improvement to useability and functionality.
I looked at the Agilent but it's too big and heavy, and for that price I'd want holdoff (not present last time I looked).

 

[Richard W.]

Has anybody experience with the Fluke 124 Scopemeter?


Richard

[saturation]

I only know of it, you can't go wrong with any Fluke scopemeters, the only question is the bang for buck.  The 124 has a 25Ms/s rate, which puts a single shot frequency response in the 2.5 MHz range. 

Has anybody experience with the Fluke 124 Scopemeter?
Richard

[Fraser]

I recently purchased a THS720 and a THM560. Sadly I have yet to have the time to give them a thorough UAT. First impressions are excellent though.

The THS......

The design is both ergonomic and rugged so it should survive working in the outside environemnt that you detail. The battery is a real pain in the backside as TEK decided to build a stick of 4 C cells with a charging ring 3/4 of the way up the bottom cells case ! New cells are easily built into a 'stick', but the charging ring needs to be constructed. I have considered modifying the charge feed to the main +ve battery terminal but I am loathed to dismantle my unit. The standard battery is an old fashioned NiCad with 2.3Ah claimed capacity. OEM TEK batteries are an ugly price. 3rd party batteries are around $80 to $100. I personally intend to build a higher capacity Sub-C cell pack with containment sleeve, fitted with the required metal charging ring. Its a little project on the 'to-do' list and is really just a mechanical battery encapsulation challenge.

Also be aware that the fully insulated BNC connectors can be fragile and get damaged. Mine are OK, but check before buying an expensive used unit.

From my limited use of the THS, I really like it and wouldn't be tempted to buy a more expensive new model just because it was new or had a colour display etc. You might even consider buying two THS units for 100% spares as it would still be cheaper than a new Fluke.  I own an elderly Fluke PM97 as well but that has been ousted by the TEK for most portable use.

[alm]

From what I've heard the Teks were the better scopes compared to the competing ScopeMeters. They were first with fully isolated channels and had the better UI. Not sure how they compare to more modern ScopeMeters.

[hacklordsniper]

I have the 199C for about 4 years now and can say for field work it never failed and survived various crap, falls, rain and what not in these years and still looks like new except the yellow rubber is a little bit dirty. I regret Fluke does not manufacture bench scopes.

If there is some specific questions feel free to ask.

[YashEE]

I recently acquired a two channel portable scope meter (model THM571) made by Tektronix (ca 1996) that has a ribbon cable (flex circuit) that was damaged from a battery leak and needs replacement.

Can these be still sourced -I think all THM500 Tek Meters use the same cable (?)

The part number is: 259008800

The picture is here:

https://www.eevblog.com/forum/testgear/tektronix-thm500-series-tekmeter-ribbon-cable-sourcing-%28%29/msg532995/#msg532995


Thanks.

[G7PSK]

A few years ago I fitted a pico scope inside a Panasonic toughbook. I removed the GPRS module and put the pico scope board in its place, the only thing showing outside of the toughbooks case was the two BNC sockets. I no longer have the scope as I sold it. The panasonic toughbook is almost indestructible, I have seen video of them being thrown of the bridge of an aircraft carrier onto the steel deck and still working and another where the case had melted in a fire and it still worked they will even stop a 50 cal bullet but in that instance the laptop did not continue to work but the man carrying it did.

[Terabyte2007]

I recently picked up a Siglent SHS806. It's a 60MHz with deep memory and data logging. Quite the versatile portable scope. They have models up to 200MHz.

http://www.amazon.com/gp/product/B00GQNNQTM/ref=oh_aui_search_detailpage?ie=UTF8&psc=1