Old Philips Fluke 97 / 96B (maybe others?)

[joeqsmith]

Post some pictures of it when you get ready to list it.   It will be interesting to see if yours is any different.

Someone should want it depending what you are asking. Prices are all over the place.  IMO, it's 20 years old and parts are no longer available so it's not worth a whole lot to me.  I see them for $500 up USD!  Used color 196 will sell for less!  Buyer beware.  I was able to basically fully check mine before buying them which swayed me along with what they were asking for them. The battery packs are not much.   I think it's a 3000 count meter is all. Specs are not that great but it's 20+ years old and fits in your hand.   

[Fraser]

My Fluke 97 kit is the original Philips/Fluke branded unit with references to the partnership in the paperwork. As it is 'as new' it has all the little extras, like the quick start guide that has magnetic front and rear covers and sits in the rear of the yellow 'boot'. In its day, it was perfect for automotive and portable usage where isolated inputs were a requirement.

I have always been surprised at the residual value of these units. I sold a pair of well used PM97 units for £160 each last year and the buyers were delighted with them. The price of spare scope probes is scary. They are good quality but you certainly pay for it. I have several spare scope probes and some of the optional modules that plug into the scope inputs. I will dig them out and take some pictures for your interest.

Fraser

[noidea]

Finally I have a lot of the optional accessories and scope probes that FLUKE sold for these units. Really nice quality but sadly they never see use in my lab. If there is no serious interest here, I will list the bits in the Forum's For Sale' area where it really belongs, then onto eBay if no home is found on this forum.
Fraser

Hi Fraser

What accessories other bits do you have?

[stj]

have you seen a probe that has a blue body with gray cable and a HUGE metal bnc connector that contains a filter or something?

i had a pair with mine and never knew what they actually were!

btw, can you use regular x10 probes on the 97?

[joeqsmith]

have you seen a probe that has a blue body with gray cable and a HUGE metal bnc connector that contains a filter or something?

i had a pair with mine and never knew what they actually were!

btw, can you use regular x10 probes on the 97?

The PM8918 was 10M//15pF.  You would want something with a plastic body like the low cost Hantek probes I like so much. 

I don't have the probe you describe but one of them is a filter probe.  It is also a 10X 10M//12pF with a 4KHz BW. 

These are some of the accessories that came with mine:

[joeqsmith]

They came with this old Tektronix 6006 probe as well.  12' cable on this one.  Makes sense coming out of a garage. 

[R_G_B_]

What are the graphing capabilities like in these scopes compared to the fluke 120 series ?

granularity  in graphing mode how low can they go per division?

[joeqsmith]

What are the graphing capabilities like in these scopes compared to the fluke 120 series ?

granularity  in graphing mode how low can they go per division?

I'm not sure what you are asking.   The 97 can go as low as 60 seconds per division.  Looking at the 123/4 they also go as low as 60sec/div.
Specs for both may be found on-line.

[Scottjd]

The Ni-Cad pack died long ago but it is is very easy to fit four standard Ni-Mh C cells and just add a small brass or copper strip that sits between the positive connection nipple and the charging tab that is below the battery. It is even easier with a tagged cell as the tag is sometimes long enough or may be extended to reach the charging tab.

Fraser
UK

Hi Fraser,
I wouldn't suggest charging the NiMH pack with the 97 or 96B internal chargers. I mentioned this in an earlier post with some testing I was doing and research during my testing.
They are designed to charge NiCd batteries and NiCd chargers have a hard time detecting when the NiMH pack is full especially at the low current rate the scope-meters charge with.  Negative Delta V to detect full charge is faint, especially when charging at less than 0.5C. The older fluke scope-meters charge with a very low current, and in addition are designed to trickle charge at a higher rate that NMH will be damaged. The built in chargers will most likely over charge the NiMH packs possibly damaging the packs or even the meters.

I know companies are selling NiMH packs claiming they are OEM compatible, but I don't think the are. I have torn down this pack and it has no additional circuitry for charge monitoring built into the pack. NiMH dislikes overcharge, and the trickle charge is set to around 0.05C. NiCd is better at absorbing overcharge and the original NiCd chargers had a trickle charge of 0.1C. The differences in trickle charge current and the need for more sensitive full-charge detection render the original NiCd charger unsuitable for NiMH batteries.

I did find one seller on Amazon that sells a 2500-2800mA NiCd pack that should work good with the built in charger. 

I'm looking into doing a mod installing another DC port that will disconnect the lack from the main board when it's plugged in, and change over to the charging tab when a DC plug is plugged in. Then I want to find a small charging board like the TP4056 but for NiMH packs.
I want to put this inline after the switch mode power supply or micro USB power supply before the DC jack and heat shrink it. If I used a micro USB board then this can be a simple adapter to use with the older scope meters with adding the DC port to charge NiMH at a faster rate and proper charging and voltage cutofff for a NiMH pack.
The wires in the battery cage are easily accessible to add this additional DC port and wire it as I described without any additional components.
I just started searching for this NiMH charger like the Li-Ion TP4056 charger. I don't know if anyone makes this already. If not then it might be a self build.  By wiring it like this I would also cut off the built in fluke charger so powering from the fluke power supply is still an option and you would also be able to plug in the additional DC jack I mentioned to charge at the same time.

Thank you,
Scott

TP charger I refered to that I'm looking for, but inenthat does NiMH charging instead.
http://www.ebay.com/itm/like/142004893160?lpid=82&chn=ps&ul_ref=http%253A%252F%252Frover.ebay.com%252Frover%252F1%252F711-117182-37290-0%252F2%253Fmtid%253D1588%2526kwid%253D1%2526crlp%253D53601919689_324272%2526itemid%253D142004893160%2526targetid%253D186358894329%2526rpc%253D0.26%2526rpc_upld_id%253D91632%2526device%253Dt%2526mpre%253Dhttp%25253A%25252F%25252Fwww.ebay.com%25252Fulk%25252Fitm%25252Flike%25252F142004893160%25253Flpid%25253D82%252526chn%25253Dps%2526adtype%253Dpla%2526googleloc%253D9014901%2526poi%253D%2526campaignid%253D239125209%2526adgroupid%253D14978428809%2526rlsatarget%253Dpla-186358894329%2526gclid%253DCP3p-pKquNACFVUvgQodoP4JlA%2526srcrot%253D711-117182-37290-0%2526rvr_id%253D1126736449119&ul_noapp=true

[Fraser]

Scottjd,

Thanks for the helpful comments on the battery chemistry best suite to the scopemeter. I just checked and I have four Radio Spares high capacity C size NiCad cells in the meter at the moment and they are tagged so can pick up the charge contact as previously mentioned. No need for a custom battery pack from ebay sellers.

I will be selling my Fluke as I have Tektronix THS-720 and 730 handheld DSO's that I would use in preference to the FLUKE unit. I will leave any battery modifications to its next owner as it is totlly unmolested at the moment 

Fraser

[Scottjd]

Scottjd,

Thanks for the helpful comments on the battery chemistry best suite to the scopemeter. I just checked and I have four Radio Spares high capacity C size NiCad cells in the meter at the moment and they are tagged so can pick up the charge contact as previously mentioned. No need for a custom battery pack from ebay sellers.

I will be selling my Fluke as I have Tektronix THS-720 and 730 handheld DSO's that I would use in preference to the FLUKE unit. I will leave any battery modifications to its next owner as it is totlly unmolested at the moment 

Fraser

Your welcome. I guess unmolested battery packs are a good thing. 
This is something as I mentioned that I was thinking about before. After seeing your comment it got me thinking again. And I just picked up 5 different Li-Ion battery packs for tools from different manufacturers for tear down. These packs usually sell about $40-$65 US and I happened to get lucky walking around a department store. The clearance isle was calling to me, I paid $5 each for three of them. So far all two of them have quality Samsung 18650 cells.

So after relying to you I realized the 96B runs off of 12VDC to 18VDC, and the charger I mentioned is nice and small. Now I'm wondering if I can make a custom Li-ion pack using this small charger.
The battery is 4.8V nominal, but the DC input external power jack will run off of 8V to 20V @6W.
Maybe 3 high capacity small Li-Ion cells wired directly to the external D.C. input jack. I'll have to take a look inside again and see how much room I have since I will need 3 cell protection and a way to balance charge them also. But your comment defiantly got me thinking again.

[PA0PBZ]

Alright, since someone mentioned (maybe others?) does this count? 

This is a weird thing, some crossbreed between a scope and a counter. It's in the same case and uses the same battery pack, and inside the processor board, the supply and the display looks very similar too. Even the A and B input channels are more or less the same. Not the C input of course, which also does not display a waveform.

Anyway, here's the beauty:

[Scottjd]

Alright, since someone mentioned (maybe others?) does this count? 

This is a weird thing, some crossbreed between a scope and a counter. It's in the same case and uses the same battery pack, and inside the processor board, the supply and the display looks very similar too. Even the A and B input channels are more or less the same. Not the C input of course, which also does not display a waveform.

Anyway, here's the beauty:

I didn't expect this one, that's neat. Thank for sharing it.
Scott

[joeqsmith]

I had charged the Cameron Sino pack using my bench supply set to 2.82 volts and 200mA doing each half separate until the current dropped (days).  Pack stayed ice cold during all of this.  Installed the pack today and then used the diode test mode you suggested last time and logged the data with a second meter.   First time I tried the pack without charging right from the box after it had sat in the scope with it turned off for a day and it ran for an hour fifteen minutes.

This time it was not much better.  Looks like it died at 6279 seconds.  No where near the other batteries.   So 584ms @ 1.744 hours gets us 1000mA/h?!  These things can't be that bad but I'm starting to believe some of the reviews people wrote about a half hour run time.   

[Scottjd]

I had charged the Cameron Sino pack using my bench supply set to 2.82 volts and 200mA doing each half separate until the current dropped (days).  Pack stayed ice cold during all of this.  Installed the pack today and then used the diode test mode you suggested last time and logged the data with a second meter.   First time I tried the pack without charging right from the box after it had sat in the scope with it turned off for a day and it ran for an hour fifteen minutes.

This time it was not much better.  Looks like it died at 6279 seconds.  No where near the other batteries.   So 584ms @ 1.744 hours gets us 1000mA/h?!  These things can't be that bad but I'm starting to believe some of the reviews people wrote about a half hour run time.   

Wow, well I just set up one of my benches as the charging station and broke all all my different chargers.
The only charger notmin the picture is the lead acid maintainer/charger for my sealed 12V and sealed 6V batteries. I use these if I need more current then I can generate on a power supply. Like testing an inverter.

One is a hobby charger, that has a discharge feature and tracks the mA used the skame as it does when it is charging. I created a jumper wire with two earth magnets to jump the pack and will charge and discharge a few cycles. I know my pack is only 3 months old.
I will then set the discharge rate to simulate the draw on the 96B around 260mA (I think that is what I measured)  current drain and see how long it holds and how much power this pack is really storing.
I'll measure my drain on the 96B again to confirm.

I can do the same with the drain based on your 97, what was the drain you meter uses?

[joeqsmith]

Wow, well I just set up one of my benches as the charging station and broke all all my different chargers.
The only charger notmin the picture is the lead acid maintainer/charger for my sealed 12V and sealed 6V batteries. I use these if I need more current then I can generate on a power supply. Like testing an inverter.

One is a hobby charger, that has a discharge feature and tracks the mA used the skame as it does when it is charging. I created a jumper wire with two earth magnets to jump the pack and will charge and discharge a few cycles. I know my pack is only 3 months old.
I will then set the discharge rate to simulate the draw on the 96B around 260mA (I think that is what I measured)  current drain and see how long it holds and how much power this pack is really storing.
I'll measure my drain on the 96B again to confirm.

I can do the same with the drain based on your 97, what was the drain you meter uses?

That's the 584mA (not ms haha) at the battery.   Chop chop with the knife.  No idea what the numbers on the side are.  Appear to be no other markings.  Last attempt will be to use my charger, one at a time. 

[Scottjd]

Now you've done it. It said no warranty if label is removed.
They don't want people looking inside and decoding numbers and find out the truth that they are dishonest with the total capacity.

[joeqsmith]

Now you've done it. It said no warranty if label is removed.
They don't want people looking inside and decoding numbers and find out the truth that they are dishonest with the total capacity.

Even worse now. Snipped the strap to not put any stress on the cells.  Code is the same on all four.  Not seeing any other markings on them. 

[Scottjd]

Now you've done it. It said no warranty if label is removed.
They don't want people looking inside and decoding numbers and find out the truth that they are dishonest with the total capacity.

Even worse now. Snipped the strap to not put any stress on the cells.  Code is the same on all four.  Not seeing any other markings on them.

The front of your wrapper is the same as mine, but on the back of the wrapper is a stamped printed code. I think this has to do with the date and battery manufacturer. I bet the stamps on the back our different.

I'm discharging all 4 cells at 1A rate. So far it's drained about 1228mA over 74 minutes and sits at a cool room temperature of 22C. Voltage is 4.64 under the 1A load, and was at 5.12V without a load before I started discharging. It dropped to 4.92V inner initial load.

I'm almost at the estimated capacity your pack was showing and still going strong.
I'm guessing you have a bad cell or one cell way off balance, that's the problem with the older Ni-MH and nicad packs. When I was a teen we raced RC 1/10th scale cars with nicad packs, of one cell died we knew it from the decreased run time. We could always recover the pack by replacing the bad cell, but it would never be the best pack for a race so it became a practice pack.

I have it set to stop at 4.1V since I don't know how well these cells are balanced, or if it was properly trickle charged and topped off. I'm guessing probably not since it was last charged with the fluke 96B nicad built in charger.
When it stops at 4.1, I will drain more at 300mA current again to 4.1V.

I'm going to charge it at 1A also, well maybe I will start at 2.5A charge and monitor the temperature. My charger has an external temp monitor and I have it set to turn off if the pack reaches 32C durring charging.
I did discover tonight that the temp monitoringndoes not monitor during discharge, only when charging doesmit monitor and fail safe if it hits the set temperature.

I contacted the manufacturer and they confirmed it will handle a 1C charge rate at 4.5A, but also hinted that I should charge it at 500mA to 1A. I guess they don't have faith in the packs they sell.

At the time of writing this it's currently at 4.53V, with 1645mA estimated drained over 100 minutes, still draining 1A current.

[joeqsmith]

Here is the code on mine.   

Charger is still doing it's thing.  Was hoping to shove them back in the scope and catch some sleep.  Could be a bad cell and why I have been watching them on the charger.  They all seem to be at roughly the same voltage.  Nothing getting warm.  This charger is fixed at 1A charge and 300mA discharge. 

Can't believe that low current fixed voltage did anything to it.  I wouldn't snip yours apart just yet.  Let's see if the independent charge does anything for this pack.  Worst case, it becomes a flashlight pack....

[Scottjd]

Here is the code on mine.   

Charger is still doing it's thing.  Was hoping to shove them back in the scope and catch some sleep.  Could be a bad cell and why I have been watching them on the charger.  They all seem to be at roughly the same voltage.  Nothing getting warm.  This charger is fixed at 1A charge and 300mA discharge. 

Can't believe that low current fixed voltage did anything to it.  I wouldn't snip yours apart just yet.  Let's see if the independent charge does anything for this pack.  Worst case, it becomes a flashlight pack....

Ok, my code in the back is.
My discharge just stopped, but at 4.4V. I thought I set it for 4.1, but I probably set each cell at 1.1. Someday I will be able to do simple math again 
So it took it down 2000mA, I will put it back on now to drain to 4.1.

I wasn't going to cut my cells apart, but I might unwrap them to see the numbers. I have PVC heat shrink for 18650 cells and should be able to use this to wrap them back up and glue the two cells next to the other two cells again. I should probably measure the diameter of these cells and the no shrunk diameter of the PVC I have first before doing this.

We picked the wrong night to go charging batteries we don't trust after eating turkey. Ok, I didn't eat any turkey yet but I'm assuming you did. We postponed our dinner until Friday because of a long night last night in the ER. Then I took a nap this at 1pm, it was supposed to be a short one like an hour but didn't wake until 6pm so I'm still wide awake.

[Scottjd]

Ok, so the numbers are different. Now we just need to crack the code.
I forgot to ask, did you measure each cell voltage before charging the cells separately after you cut them apart?

[joeqsmith]

Ok, so the numbers are different. Now we just need to crack the code.
I forgot to ask, did you measure each cell voltage before charging the cells separately after you cut them apart?

Yes, and then marked them.  They were in the same ballpark.  Maybe I needed to raise the voltage a bit more and did not have them fully charged.  More curious than anything.  I plan on using the other cells or get me some of those batterfryers and see if it runs for double the time.     

Funny they changed the orientation of the code between the two packs.

Yea, I had enough to eat, just have not unwound yet for the day.  Almost time to get up anyway.     

[joeqsmith]

I finally died after 29570 seconds or 8.26 hours.  At 584mA, 4821mAh.  Seems the pack does meet their claimed 4500mAh but I just don't know how you would go about charging it with the scopemeter.   

[Scottjd]

Just checking in on the battery test.  Almost 5 hours now and so far it's looking good! 

One thing that I am finding is when I had bought this PC with Windows 10, NI had dropped support my GPIB Ethernet controller.  I had sniffed the bus and just talk with the controller directly now.  This works so much better than it ever has.

Nice, that's longer then I originally estimated. Oh wait, I never estimated the run time. I only estimated charging time for the pack with the built in charger.  Over 8 hours, wow. Then maybe the  96B might pull over 10 hours.

I was lucky and managed to get a real keysight GPIB to USB adapter, not one of the many fakes on eBay. I think I installed the driver and changed the run mode on the application for backwards compatibility in the properties of the executable. I don't remember the details and bought a new laptop so I don't currently have the software installed. When I ran my run time test I use my Fluke 289 for logging. I need to set the remote interfaces and software back up again on my new laptop someday.