Test Equipment Anonymous (TEA) group therapy thread

[shakalnokturn]

Given how little there is on the web for the chipset, it would be wise for me to find another Danameter & attempt to make a good one out of the two.

David

I wonder how many chances that would give you of having two bad LCD's... 

[factory]

Yes it's a high probability, as they will be advertised as untested, with some excuse such as "I don't know how to put a battery in this". 
There is at least one Danameter with a functional LCD, which is in a recent thread on the RacalDana groups.io.

My searches were full of Monolithic Power Systems.

Looking at wiki, they didn't exist in the mid 1970s or the 1980s when the DMM was made.
There is nothing for Micro Power Systems on wiki, very odd, wonder what happened to them? maybe taken over?

They had enough devices to fill a 350 page databook; https://www.ebay.co.uk/itm/362633260744

Could this be the reference used? https://www.silicon-ark.co.uk/discounted-micro-power-systems-components-from-silicon-ark-co-uk/mp5010mt-tempco-voltage-reference-micro-power-systems

David

[shakalnokturn]

I've been chasing around the WWW with Micro Power Systems address of the time, which led me to a few company numbers indicating trouble in '88 then serious trouble in 1992-1994.
Address changes to Palo Alto (Holdings Acquisition, Inc.) in '94.
Then at one point address changes to: 48720 KATO RD Fremont

Which funnily is linked to EXAR / MPS (Monolithic Power Systems this time).
Then around 2016-2017 EXAR is bought by ASUS and/or MaxLinear.

https://en.m.wikipedia.org/wiki/Exar_Corporation
https://www.procureinc.com/manufacturer/MicroPower_Systems_-_Exar/

[Robert763]

Looks like it was set up by Dr. John Hall and then sold to Exar. He was an intersil founder and also set up Linear Integrated Systems.
https://en.wikipedia.org/wiki/John_H._Hall_(inventor)

[m k]

Could this be the reference used? https://www.silicon-ark.co.uk/discounted-micro-power-systems-components-from-silicon-ark-co-uk/mp5010mt-tempco-voltage-reference-micro-power-systems

David

My take is that it is.
I searched MP5010, but adding MT is less intuitive.

Seems that I should change my method and just ask Noopy.
https://www.eevblog.com/forum/projects/dacs-die-pictures/msg4333342/#msg4333342

Seems also that AD happened.
At least MP750x and AD750x datasheets are very similar.
5000 series is missing, ref. is also usually something else.
Some ADE things seem to have 1.2V something.

[factory]

Thanks for all the info, almost lost to history with the name changes & take overs.

I've had another look inside the Danameter, the reference is indeed a Micro Power Systems MP5010 (no suffix), LCD controller is a MP7104AN.





Attached is the circuit diagram & component layout.

David

[med6753]

Started working the Tek TM503 with DM501, FG501, and PS503.

First task was cleaning up years of dust and dirt.

Before


After


The cover before


After cleaning. It does not need painting.


Next step is checking the main supply voltages. The +37V and -37V were OK. The 11.5V read 7.7V with almost 2VAC ripple. Open 11000uf capacitor which was replaced. The filter caps for the 37V supplies still need to be changed and they are going to be a bitch to remove.

 

The first module to be tested is the DM501. I had high hopes that it would work but alas that was not in the cards. With an applied voltage of 2.500VDC reading is as shown. And it can't be brought into spec with the DC cal. The ohms is also somewhat flaky and why doesn't this DMM have a 200 ohm range? Lowest range is 2K. That's ridiculous. I did a quick scan of Ebay and almost every one of the DM501's for sale do not work. There must be an inherent issue with these DMM's. Given that this unit isn't worth my time to fix and will be a parts unit. And it's already given up a part to fix something else.

 

Next up is the FG501 Function Generator. This unit was completely dead. No output. A check of the internal voltages determined that the +17V and -17V were reading 5.09V. U430, a 741 op-amp, was dead. Replaced it with a 741 IC from the DM501. The unit came to life with output.



Next step is re-cap.




Final step is calibration. Required minimal adjustment. This unit is now complete.



Some sample wave forms. The output impedance of the FG501 is 50 ohms so the vertical input of the 2465 was set to 50 ohms.





Next to be tested and re-capped is the PS503.

[shakalnokturn]

Thanks for all the info, almost lost to history with the name

I had a last look in the IC Master 1983 Volume 1, the MP7010 is there with plenty of cross-references. The MP7104A also figures as "DVM logic" without further detail, there's nothing to be seen on the MP7005R.

None of the MPS devices in the document use the "R" suffix so I'd assume it's a custom job for Racal.

I had no luck in finding EXAR databooks from '95 just after the change of hands when those products may not quite have been obsoleted, it seems that EXAR abandoned printing by then and any digital trace - if it exists - is on CD-ROM in a dusty drawer, nothing downloadable.

[m k]

So MPS was finally a regular manufacturer, just not regular for us.

My guess is that both of those chips are special for that case.

I read that somebody pulled out somewhere in the middle of a big thing, not AD, and was sued.

First I thought that EXAR didn't get it all, but maybe it did.
Now it seems that majorly MPS was just one factory among others.
Maybe part of 57xx was their own.

[Andrew_Debbie]

I've had another look inside the Danameter,

I doubt my little Racal-Dana / Dana collection will ever have more than a handful of exhibits.   Always great to see inside one that is unlikey to find a space on my bench.


My first engineering job and only metrology job involved a lot of Racal-Dana gear.    We were next door to their Irvine CA facilty. 

A few Toys that I could only dream of owning back then are now mine.

[Robert763]

I saw this https://www.ebay.co.uk/itm/387122814110 and put a small bid on it. It looked interesting and if nothing else I'm a sucker for a pelicase. The item is a Prostat electrostatic test kit. My bid was what I'd pay for the pelicase. Didn't really look at the contents other than noting it had a surface resistivity meter (analog) and two 5lb test electrodes.
Anyway there was only one other bid and I won it for fraction of my bid amount. Less than £12 including shipping 
So I then looked at it in detail. The seller does not list everything in the kitbut at least the surface resistivity meter and electro static field meters are still current models under different names. The resistivity meter https://uk.rs-online.com/web/p/esd-testers/2325533 and field meter https://uk.farnell.com/desco/19442/esd-tester-digital-static-field/dp/4047166
Note the cost, £850 and £930 ($1100 and £1200) 
They look unused. Lets see what turns up.

Robert.

[McBryce]

I saw this https://www.ebay.co.uk/itm/387122814110 and put a small bid on it. It looked interesting and if nothing else I'm a sucker for a pelicase. The item is a Prostat electrostatic test kit. My bid was what I'd pay for the pelicase. Didn't really look at the contents other than noting it had a surface resistivity meter (analog) and two 5lb test electrodes.
Anyway there was only one other bid and I won it for fraction of my bid amount. Less than £12 including shipping 
So I then looked at it in detail. The seller does not list everything in the kitbut at least the surface resistivity meter and electro static field meters are still current models under different names. The resistivity meter https://uk.rs-online.com/web/p/esd-testers/2325533 and field meter https://uk.farnell.com/desco/19442/esd-tester-digital-static-field/dp/4047166
Note the cost, £850 and £930 ($1100 and £1200) 
They look unused. Lets see what turns up.

Robert.

A highly unfortunate choice of name. My first thoughts were "I hope he wiped it down before using it. Who knows where it's been".

McBryce.

[factory]

I've had another look inside the Danameter,

I doubt my little Racal-Dana / Dana collection will ever have more than a handful of exhibits.   Always great to see inside one that is unlikey to find a space on my bench.


My first engineering job and only metrology job involved a lot of Racal-Dana gear.    We were next door to their Irvine CA facilty. 

A few Toys that I could only dream of owning back then are now mine.

This would probably not have been regularly used either, if it didn't have a failed LCD, but I will still try & see if I can find something to replace it with.

I have family (grandparent) that once worked for Racal, no idea which division, but somewhere in Bracknell, he passed when I was too young to think about asking more. We used to repair some Racal communication equipment (crew & PA comms) & the auto announcer used in some trains, all history now since the wasteful employer I work for, unceremoniously skipped everything a few months ago. 

For anyone interested the Racal-Dana Danameter 2000A instruction manual is now available on the BAMA archive; https://bama.edebris.com/manuals/racal/2000a/

Edit: Somehow I missed the Dana 2000/2100 service manual at BAMA, I noticed it when updating the RacalDana groups.io database to add the 2000A manual link.

The service manual is much more detailed, there are diagrams for the 5007, 5007R, 7104, 7104A ICs, note the later parts with suffix are not interchangeable with older parts. It also has details of what is inside the custom resistor/capacitor networks.

Also the earlier Danameter had a Mercury cell as the voltage reference, there is instructions for updating this with the later reference zener.
The three bodge resistors are a modification to prevent multiple decimal points showing with higher humidity.

Edit 2: Forgot the link to the Dana service manual at BAMA; https://bama.edebris.com/manuals/dana/2000/

David

[KG7AMV]

Cami Research M2 CableEye Cable Tester. Anyone else have one?

[m k]

Edit 2: Forgot the link to the Dana service manual at BAMA; https://bama.edebris.com/manuals/dana/2000/

David

Racal manual has clearer schematics, Dana has more details, but then it hasn't.
Keep both.

One other version I found is substandard.
Must wonder how so bad ones are not scanned again.
Some other models had tons of pages of fog.

When calculators moved away from single digit approach they didn't hesitate using multiple modules.
That is a bit far for the sign part of a meter, but maybe some other category has a surprise.
Can there be a clock with multipurpose display module, I think I've seen some.

[Robert763]

Cami Research M2 CableEye Cable Tester. Anyone else have one?

I have a Paladin 1570 which does about every cable on those adaptors plus some. It does not need a PC to operate. Basicalls two sets of LEDs one for input (source) and one for output (detector). It just sequences the source pins high as you prees a button. detector shows what thet pin is connected to, or not.
[ Specified attachment is not available ]

Great bit of kit.
Robert.

[Andrew_Debbie]

Spotted on eBay -- Racal Dana 1998 Frequency Counter.  Listing description claims it is fully working.   Starting bid is £45.   No bids (yet)

Back panel says it has Options 04c and 55.    04C is the basic uncompensated crystal oscilator.    Option 55 is GPIB, but I don't see the connector.     Of course actual options may not match what is inside the box.     

04c was intended for use with an external reference.   The uncompensated crystal is just there to provide proof of life.   


Collection only from Aylesbury, UK .   Too far.  I won't be bidding.

https://www.ebay.co.uk/itm/305661687021

EDIT:  Seller has two of them.   

This one has the GPIB module -- > https://www.ebay.co.uk/itm/305661686705

From the back panel it looks like this one didn't have GPIB when it left the factory.  Someone likely moved it into this one. 

Possibly bought at auction and reselling ?? Dunno.   No idea.    Nevertheless £45 is not a bad price if it works.    They also have an older 1992 starting at £65.

[McBryce]

Spotted on eBay -- Racal Dana 1998 Frequency Counter.  Listing description claims it is fully working.   Starting bid is £45.   No bids (yet)

Back panel says it has Options 04c and 55.    04C is the basic uncompensated crystal oscilator.    Option 55 is GPIB, but I don't see the connector.     Of course actual options may not match what is inside the box.     

04c was intended for use with an external reference.   The uncompensated crystal is just there to provide proof of life.   


Collection only from Aylesbury, UK .   Too far.  I won't be bidding.

https://www.ebay.co.uk/itm/305661687021

EDIT:  Seller has two of them.   

This one has the GPIB module -- > https://www.ebay.co.uk/itm/305661686705

From the back panel it looks like this one didn't have GPIB when it left the factory.  Someone likely moved it into this one. 

Possibly bought at auction and reselling ?? Dunno.   No idea.    Nevertheless £45 is not a bad price if it works.    They also have an older 1992 starting at £65.

No sign of option 55. Looks like he has cobbled several devices together to make complete devices and he also doesn't show it running. Wouldn't touch it with a barge pole.

McBryce.

[factory]

There are more under their sold listings, who knows where it's come from, too many of the same items for a private seller IMO. Maybe emptied a skip where they work?? Collect only is a bit odd too.

David

[tggzzz]

There are more under their sold listings, who knows where it's come from, too many of the same items for a private seller IMO. Maybe emptied a skip where they work?? Collect only is a bit odd too.

Might give an opportunity to verify all operation before handing over money. But if that wasn't possible, run away!

[Andrew_Debbie]

Exactly.   For £45 and proof that it works at collection, not a bad deal.    Seller advertised it as fully working, so it is within eBay rules to refuse / return if it does not work.

My guess those are lot numbers from an auction.   Seller bought all of them cheap and is looking to flip at a profit.        Option 04C indicates whereever they orignally came from  had a house 10Mhz standard,  rubidium maybe.   These things predate GPS.


This one, with the GPIB option intact,  sold for £45.   https://www.ebay.co.uk/itm/305643839353

If it works, buyer did reasonably well.

[HalFoster]

Not full on TE porn, but pretty:

[AVGresponding]

Oh, I don't know, that's a thousand dollar bench, and then some!

[m k]

Exactly.   For £45 and proof that it works at collection, not a bad deal.    Seller advertised it as fully working, so it is within eBay rules to refuse / return if it does not work.

My guess those are lot numbers from an auction.   Seller bought all of them cheap and is looking to flip at a profit.        Option 04C indicates whereever they orignally came from  had a house 10Mhz standard,  rubidium maybe.   These things predate GPS.


This one, with the GPIB option intact,  sold for £45.   https://www.ebay.co.uk/itm/305643839353

If it works, buyer did reasonably well.

42 and 39 have had labels above input B.
38 has a small round pink sticker beside power button and has had a label above middle buttons.
The pink one has a number and others can be cal stickers.

I think I wouldn't have removed cal stickers.

[med6753]

Continuing with the TM503 project.

This is the PS503 Power Supply after re-cap.



After replacing the electrolytics and before replacing the tants decided to do an initial test. The supply came up fine, for about 5 minutes, then the positive supply went into current limit. C155, a 100uf/20v tant, got warm but did not flame because there wasn't enough available current. Verified shorted. Bloody tants. This is why I always replace them.



The vanquished. One of those blue tants was the short.



The supply now works. This is dual track mode. The fixed 5V is OK too.

 


Calibration was simple and uneventful. This project is now complete. I'll eventually find another module for the vacant slot. But a quick scan of Ebay and you would think these modules are made of gold and platinum. The prices are stupid.