Frasers equipment re-homing begins

[JPortici]

Gloating. And keeping an eye

[Fraser]

I am still feeling somewhat battered after yesterdays surgery, but I have decided to post something a little special (to me anyway) that may interest those wanting a portable and safe DSO. This is a quality FLUKE-Philips PM97 portable LCD DSO 

So why is this unit "special" ?

FLUKE went into partnership with Philips to produce a very advanced (for its time) portable DSO with LCD screen and excellent safety aspects to protect the user from high voltages. This DSO became the darling of anyone working on mains powered PSU's, Electrical systems and Automotive diagnostics. It found a welcome on the benches of mobile and fixed techs as a convenient and well made DSO on which they could rely. The unit was designed and built in the 1990's but still has a following in the 21st Century. This is testament to its reputation and quality.

This particular example that I am offering up for re-homing is special in another way as well..... it is virtually as-new 

This PM97 was one of a pair that I owned. I bought two in order to have a spare in case of failure. The failure never happened and I sold my 'daily use' unit a couple of years ago for close to £120. It was well used and nowhere near as nice as this unit. This PM97 has NEVER seen active service beyond occasional charging and testing. The screen is unmarked and the marks on the yellow case rear feet only come from sitting on a bench whilst charging. so whilst I cannot state that this PM97 is new, I can state, with some confidence, that it is likely the best condition unit you are ever likely to find outside of the FLUKE museum !

The unit comes with the extended set of test leads and adapters that cost a small fortune on their own. This is a comprehensive test lead set that suits the varied use of such a portable DSO  The DSO scope probes alone cost upwards of £60 each normally.
I have also included spare scope probe earthing cables as these do take a beating in normal use. The probes and cables have been unpacked but are unused.

I do have some more optional accessories for this DSO but they are not included in this sale. They may be made available in future posts or if the buyer requests first refusal on them.

The battery pack in the PM97 was just four Ni-Cad 'C' cells with a tab on the positive that connects to a charging plate in the battery bay. The NiCad battery pack failed many years ago (as they do when not used). I have tested the unit with some standard Nicad 'C' cells and all is well with it. The new owner can either use some nice Ni-Mh 'C' cells in the unit or buy a ready made battery pack. I can include the 'C' cells that are currently fitted but I offer no guarantee on their remaining capacity so budget for buying four 'C' cells.

Battery hacking information is provided here:

https://www.edn.com/electronics-blogs/other/4306687/Hacking-Old-97-Part-1-Batteries

As can be seen in the pictures, the LCD display is perfect with sharp definition and a nice bright backlight that may be switched on and off as desired. There is no age related degradation evident in the display or the backlight.

This is a lovely example of the FLUKE-Philips PM97 and I see no reason why it should not perform well for its new owner for many years to come. I doubt another will be seen in this amazing condition any time soon, if ever. Remember, it has just been dry stored all its life since new !
 
OK, now the usual information for potential buyers:

Make: FLUKE-Philips partnership
Model: PM97
Type: Portable 50MHz LCD Scopemeter DSO
Condition: As New, or as close to it as possible 
Offers Over: £??? See Below
Shipping: At cost to Worldwide destinations

Comments: Provided above.

Specifications:

http://www.original-heuss.de/de/privat/Download/Philips-Fluke_ScopeMeter_PM93-95-97_web.pdf
https://www.testwall.com/wp-content/uploads//2015/09/FLUKE_90SERIES94925.pdf

Manual: http://argentinosenalemania.de/ebay/pm95/pm95.pdf

Service Manual:

https://elektrotanya.com/philips_pm93_95_97_fluke_93_95_97_sm.pdf/download.html
http://bee.mif.pg.gda.pl/ciasteczkowypotwor/Fluke/PM97.pdf

OK, so why no "Offers Above" guide price ?

Well this is a rare opportunity to buy an amazing condition FLUKE Scopemeter and I honestly do not know what guide price to set. This is a problem as I do not want to over price it , yet I know it is a special unit that is worth more than the £120 I sold its heavily used brother for two years ago. I propose that in this case, any interested parties seriously consider what they would be willing to pay for this unit and send me your offers. I will be fair about this but do want to raise a sensible sum for this unit. I have kept it this many years as I could not bring myself to sell it. My gut feeling is that it is worth at least £200 but I leave that to those interested in owning it.

ABEX in the UK are advertising a used PM97 with failed backlight for £395 

https://www.abex.co.uk/esales/test/philips/oscilloscope/pm97/dm5971524_s02421/index.php

Pictures attached

[Fraser]

Continued.....

[Fraser]

Comprehensive test lead pack.......

[Fraser]

Backlight demonstration. Good contrast and bright 
The last two images are with a torch shone on the DSO, yet no LCD backlight wash-out 

[Fraser]

 SOLD

OK, another unusual listing for today 

This is a SPARES OR REPAIRS sale listing

I used to use a Tektronix 2710 1.8GHz Spectrum Analyzer until one day it switched on and POP! it died 

This is around 10 years ago so I am working on my failing memory as to what happened next.

I recall that I obtained the service manual (I believe I still have it) and I investigated the power supply section of the analyzer.
Visual inspection revealed failing mains input filter capacitors but no obvious other capacitor failings. Tests showed the power supply section to be totally dead. It uses an inverter and that was not running. I tested the drive transistors in the inverter and they had both failed. I took a pretty holistic repair approach that involved replacing many of the electrolytic capacitors, the main switching transistors, controller IC and some other IC's in the power supply that could have been damaged when the inverter drivers failed. I did what checks I could before re-applying power. I was told that these power supplies do not like a test variac slow supply increase so I went for a straight power on and .......... POP! Ther was that horrible smell of fried silicon again 

I investigate what had died and discovered that a second pair of switching transistors in a later stage of the power supply had failed and I believe take the new 'upstream' transistors with them. I can only think that the 'downstream' transistors had caused the original fault or were damaged by the failure earlier in the inverter stage. I felt very daft as I am not sure that I tested those downstream switching transistors and and as they take a lower voltage supply (IIRC it is approx 60V) from the previous inverter stage I could probably have live tested them with a power supply. I was was very miffed with myself I can tell you. It was a classic case of hurrying a job and I paid for it. Faced with replacing both pairs of switching transistors, the controller IC and other IC's once again, I ran out of time and interest and put the unit back together to await a day when I had more time and patience. That day never came as I bought a lovely Advantest R4141 that I used and so forgot all about the TEK 2710.

Well that poor sick 2710 has been unearthed in the lab and needs to find a new home where it can either become a repair project, or valuable spare parts fro another 2710 SA  From what I have seen over the years, spare 2710 PCB sell quite well on eBay but I have no desire to gut this nice analyzer. If someone else does, fine, but it is not my style.

Prior to the failure I had fitted the very expensive big 'flying saucer' shaped Lithium battery. This was done in the recommended way with a current limited supply across the Lithium battery rails during battery replacement. The 2710 worked fin afterwards. Those special Lithium batteries are really expensive  I did not get much use out of the new battery before the POP! ended play 

OK, so I am listing this TEK2710 here for rehoming. It is a lightweight' SA so can be shipped overseas but the cost may still be quite high, depending upon destination. The unit is sold as SPARES or REPAIR and I can offer no repair help or guidance. It will be your project... enjoy 

I have photographed as much as I can of the unit, it's power supply section and the removed components. I refitted all of the case screws and buffers in preparation for travel.

The usual listing details follow.

Make: Tektronix
Model: 2710
Type: Portable Spectrum Analyzer 10KHz to 1.8GHz
Condition: SPARES OR REPAIR Definitely a fault in the power supply. Other faults not known. Rear feet damaged.
Offers Over: £60 (By PM Please)
Shipping: At cost to Worldwide destinations

Comments: Provided above.

There is a TEK Wiki for this unit !

http://w140.com/tekwiki/wiki/2710

Specifications: https://testequipmentconnection.com/specs/TEK%202710%20SPECS.PDF

Manual: http://w140.com/tek_2710_operator.pdf

Service Manual: http://w140.com/Tektronix_2710_Spectrum_Analyser_Service_Manual.pdf

Pictures follow.....

[Fraser]

Continued......

[Fraser]

Continued.....

[Fraser]

I just had a quick look at the 2710 Service Manual to refresh my memory.

Page 361 of the service manual referenced in my previous post shows the relevant schematic.

The Power Supply uses a pre-regulator stage. It was switching transistor Q480F that had initially failed.
The pair of transistors that failed after my attempted repair were Q453F and Q355F. I am sure I checked them at the time and they were initially OK, but then failed. The pair of switching transistors form the transformer drive that is supplied with 60V from the pre-regulator stage driven by Q480F.

Looking at this now, I am almost tempted to revisit it and repair the power supply. It does not look that difficult  . In truth though, I have better things to do with my time. This could be a very cheap and nice Spectrum Analyzer project for someone though   . PSU faults can be pigs to diagnose and may look scary, but they are eminently repairable in most cases 

Fraser

[Towger]

For those with less will power than me, a
Tek 2710 power supply board is available from China: https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F251417186295

It is not your every day 'simple' SMPS.  :-)

[nfmax]

PSU faults can be pigs to diagnose and may look scary, but they are eminently repairable in most cases 

Especially if you have a PM97 handy!

[Towger]

And buy multiples of all replaced parts.  The spares come in handy each time you are 'sure' all blown parts are replaced.  On each attempt add additional replacement candidates...

The PM97 becomes useful when beyond the bang stage!

[DuPe]

Hello Fraser,
does the R3132 come with option 74 (tracking gen.)?
Cheers
Peter

[Fraser]

@ DuPe.

No tracking Gen fitted.

Fraser

[DuPe]

Thanks a lot for the fast reply

[Fraser]

There will be a break in proceedings until 7th May as duty calls elsewhere. Small items that I am due to get shipping quotes on will likely be dispatched as planned.

As Arnie Schwarzenegger would say ...... I’ll be back 

Fraser

[Fraser]

[bitseeker]

Nice store sign, Fraser.

[kripton2035]

happy customer of first batch of Fraser's lab re-homing.
this baby has a new home.
thanks Fraser !

[Fraser]

kripton2035,

You are most welcome. I am pleased that it has gone to a good home where it will get some use !

I must find the schematics for you. I have them in my archive. If you need the electronic copy of the user manual, just let me know.

Best Wishes

Fraser

[kripton2035]

I already found the user manual online, but I would like the schematics if they are available. thanks.

[extide]

Wow, awesome deals here. Very tempting but the whole shipping to the US thing... Hrmm, will wait to see what else comes up.

[kripton2035]

You are most welcome. I am pleased that it has gone to a good home where it will get some use !

well it has already found a defective component on a board that was sitting here for some months ...
the comparaison mode between two boards is a killer feature ... (if you have a spare working board !)

[Zucca]

Now I know what a Huntron Tracker is and I want one. 

Well... maybe my Keithley 2400 can do it.

[Fraser]

The 210 is a modern, more advanced Huntron Tracker designed for modern low voltage chips. It is just a progression in the development of the very old octopus I-V testers. The original Huntron Tracker was/is loved by service techs as it can either show the lissajous display for components or compare the lissajous signature for any point on a PCB with that on a known good board that is the reference. The display switches back and forth between the reference and the board under test. In this way it quickly identifies faults in power supplies, discrete component boards and even I/O gates on chips.  The 210 was developed as an accessory for oscilloscopes rather than a complete unit with display. This lowered its cost a little, but it was still expensive ! Additional low voltage ranges were added to work with today’s modern low voltage logic. An internal stimulation voltage generator was also added as a convenience for testing gated components whilst monitoring the lissajous figure. I bought the 210 with high hopes for it, but sadly it really did not get used. I have used the original Huntron Tracker a lot and it is a very convenient little package. A lot of research went into whether a Huntron Trackers test voltage and current could damage sensitive silicon junctions. The results showed no damage or degradation in the junctions under test as the limited current prevented overheating. With the advent of very low voltage logic, Huntron did advise caution as such components could be very fragile. Hence the new low voltage Huntron Tracker testers were developed. Great bits of kit, one and all 

Fraser