HP LCR/LCZ Comparator Handler Interface Recreation: 16064A

[ZGoode]

I have an HP 4277A LCZ meter which can be run in a comparator mode for binning parts, but can't find the parts necessary anywhere to add that option to my unit.  I have found a handful of pictures online of the unit and boards which should hopefully help in beginning the reverse engineering process.  If anyone has a unit with the compatible board or option installed I would greatly appreciate if they could take some pictures of the boards so I can try and create a schematic/board.
Another unfortunate feature of this option/board is that it appears to have a manual separate from the LCR/LCZ meters, so the schematics are not in those manuals.  I have had minimal luck tracking down the manual for the 16064A, but I have found the manual for the 16064B, which while not compatible appears to be very similar.

[TERRA Operative]

Here's the plugin module PCB layout, gerbers and rear panel design files.

I pulled the module from my instrument, desoldered the parts, scanned the PCB (then reassembled and reinstalled) and drew up the PCB design.
I still have to back-annotate to a schematic, but I'll do that later.
This is a 100% functional copy, and almost 100% cosmetic copy too. I just used standard footprints in Diptrace for the passives, so their spacing is inconsequentially slightly different to the HP design, but it makes no real difference.

The brackets for attaching the PCB to the rear panel will need to be fabricated. I haven't altered the design there at all, so it currently matches the HP design exactly.
If an easily available part is decided on, I can update the files to suit.

All the IC's are 74LS series, but they should be able to be replaced with 74HCT without any trouble.

Also, the Centronics connector could probably be replaced with a PCB mount type to ease assembly by eliminating the need for ribbon cable jumpers if we wanted. Something like NorComp part 112-036-213R001 would do it.
A minor change to the PCB and rear panel would be needed but nothing too difficult.


The BOM is as follows:

IC1 - 74LS245N
IC2 - 74LS244N
IC3 - 74LS164N
IC4 - 74LS00N
IC5 - 74LS244N
Resistor Arrays (x2) - 4.7K 8-way ganged - Bourns 4609X-101-472LF
Resistor - 10K 1% 1/4W
Ceramic capacitor - 0.1uF
Electrolytic capacitor - 220uF 25V
Diodes (x2) - 1N4148
Centronics Connector - NorComp 111-036-203L001



As for the control box, I don't have one to copy, and I don't have a copy of the user manual for this option either. I posted a request for a manual on the HP/Agilent/Keysight Groups.io page but no response yet.
I see manuals on eBay, but the sellers are asking like $50 or more which is a silly price....

[ZGoode]

Those are fantastic images!  That was extremely fast!
Yes, I agree with you, I will swap it out for a board mount connector in my design.  Based on the scans you uploaded, I think I can get a preliminary schematic done in a day or two.
Shame to see I am not the only one who hasn't had any luck tracking down that manual.  I reached out to a company local to me who claimed to have the part number associated with that manual, but it turned out to be the B variant and not the A variant needed for this plugin board.  I also tried talking to the Keysight rep we have for the school, and unfortunately they were not able to locate an old copy either.
Luckily though, the B version manual is still available on the Keysight website and that includes a schematic.  Odds are the B version is very similar to the A version as it seems to be nearly identical, just without the keypad we need for ours.  Based on the number of pins used on the connector it is most likely some kind of multiplexed or charlieplexed solution, which will take some trial and error to figure out.

[ZGoode]

I've finished up with my copy of the 16064A interface board.  My next plan will be to try and copy the interface controller.  Hopefully the 16064B manual will be able to give some insight even though it is a little different.
My schematic is a little ugly, so that will need some cleaning up, but I'm happy with the board layout.

[TERRA Operative]

Yeah, A schematic of the A model would be perfect if we could find one, but the B model might get us close.
I've been looking here in Japan, but nothing at all has come up so far. They have to exist somewhere though, my unit had the plugin board so I know at least one 16064A existed in Japan at one point in time.....


I also have one small off-topic request for your Keysight guy if you don't mind....?
Can you ask them to dig around to see if they can find the 'Adjustment Program', part number 04263-65005 for the 4263A and 4263B LCR meters?
I'm desperately trying to track it down and am having no luck so far at all....

[ZGoode]

Yeah, can do.  I'll ask around about the 4263A/B.  Is that a manual of sorts or is it a floppy disk/eprom?

[TERRA Operative]

It's a BASIC program, so would have originally been on floppy disk. Could be on a computer somewhere, but even scans of a printout or screenshots of the code is fine.

[ZGoode]

Got my hands on a 16064A handler interface.  I have disassembled it and taken pictures.  I would have scanned the board on a flatbed scanner, but I can't find a safe way to remove the centronics connector from the edge of the board to do so.  (I need to double check the resistor values, but if I am reading the color codes right, the values I have seem reasonable)
The components on the board are all off the shelf components, except for 2:
 - 1x 7407N
 - 1x 7445N
 - 2x 74LS244N
 - 1x 74LS138
 - 2x 74LS273N
 - 1x 74LS32N
 - 1x 74LS05
 - 2x green 5mm LED
 - 4x red 5mm LED
 - 6x sets of three pin headers, each with a 2 pin jumper
 - 1x pushbutton SPST-NO
 - 6x small weird red LED
 - 3x 4.7uF 25V Tantalum Capacitor
 - 1x 36 pin centronics connector
 - 2x 12 pin right angle header connectors
 - 3x 10 pin 9 resistor 4.7k resistor pack (4310R-6F4-472LF/MSP10A01-472G)
 - 2x 8 pin 7 resistor 470 resistor pack (4308R-94Y-471/MSP08A01-471G)
 - 1x 1nF 5% 100VDC ceramic capacitor
 - 2x 10nF 10% 100VDC ceramic capacitor
 - 4x 464 1% resistor
 - 2x 178 1% resistor
 - 2x 10k 1% resistor
 - 1x 1k 1%


The 2 weird parts not off the shelf are the 2 HP labelled IC's.  I could not find anything at all for these components anywhere on the internet, as far as I can find, they don't exist anywhere else.  Based on the capacitors and resistors setup around them I am under the assumption that they are some kind of comparator or amplifier, but have not confirmed that yet.
 - 1x 900 602 8828
 - 1x 900 577 8834

[ZGoode]

More pictures due to the 8MB file limit

[ZGoode]

More pictures due to the 8MB file limit

[ZGoode]

More pictures due to the 8MB file limit

[TERRA Operative]

What's the exact size of the PCB?
I'll stitch it together in Photoshop to make a shape-corrected image of the PCB.

(If you have a heatgun, it would make short work of removing the centronics connector).

[TERRA Operative]

The 2 weird parts not off the shelf are the 2 HP labelled IC's.  I could not find anything at all for these components anywhere on the internet, as far as I can find, they don't exist anywhere else.  Based on the capacitors and resistors setup around them I am under the assumption that they are some kind of comparator or amplifier, but have not confirmed that yet.
 - 1x 900 602 8828
 - 1x 900 577 8834

Those two, the '8828' and '8834' are the date codes (28th week of 1988 and 34th week of 1988).

So the part number would probably be some combination of 900 602 and 900 577. Sometimes a first digit will be dropped due to space constraints on a small part, so the part number could be something like 1900-0602 etc (HP part numbers are in the xxxx-xxxx format).
It looks like 1900-xxxx part numbers are diodes, 1901-xxxx looks like discreet semiconductors like diodes and LED's etc. Integrated circuits and transistors seem to be 18xx-xxxx part numbers, with integrated circuits being around 182x-xxxx.

Looking at the passive components and stuff around them, maybe either opamp's, optocouplers or voltage regulators maybe?

[ZGoode]

Yeah, I tried looking up different combinations of  900-602 and 900-577 with no luck.  They could also be voltage regulators or optocouplers as you suggest, I just assumed opamps due to the oddly specific resistor values surrounding them.  I got a delivery of new transistors today to try to get my 4277A power supply up and running again.  If the transistors do the job, I can plug the handler into my unit and test it, since I already have the replacement interface card from JLCPCB assembled and ready to go.
I do have a heat gun, but I'm worried about scorching the board since the only one I have with a high enough wattage for this gets super hot.  And it isn't like this is an easy board to find a replacement for.  I don't have a temperature-controlled one with enough power to remove the connector.

[Kean]

Desoldering a connector like that with joints on both sides is a pain.

A perfect use case for Chip Quik alloy with low melting point.  You want to use braid to remove all existence of it afterwards.  Pity it isn't cheap.
https://www.chipquik.com/store/index.php?cPath=200

Otherwise I would cut the old connector off (e.g. Dremel), desolder the left overs, and replace it with a brand new one when done.
A similar Centronics connector shouldn't be too hard to source.

[TERRA Operative]

What's the exact size of the PCB?
I'll stitch it together in Photoshop to make a shape-corrected image of the PCB.

@ZGoode Did you manage to get the PCB dimensions?

[ZGoode]

The approximate measurements of the board are 3.5" x 10".  Although, it would probably be more accurate to use the 0.1" hole spacing of the DIP IC's as a reference

[TERRA Operative]

It's hard to use the board features as a reference due to perspective and parallax. Are you able to measure it more precisely? A decent ruler should get you to half a millimeter if you don't have calipers.

[ch_scr]

The 2 weird parts not off the shelf are the 2 HP labelled IC's.  I could not find anything at all for these components anywhere on the internet, as far as I can find, they don't exist anywhere else.  Based on the capacitors and resistors setup around them I am under the assumption that they are some kind of comparator or amplifier, but have not confirmed that yet.
 - 1x 900 602 8828
 - 1x 900 577 8834

Those two, the '8828' and '8834' are the date codes (28th week of 1988 and 34th week of 1988).

So the part number would probably be some combination of 900 602 and 900 577. Sometimes a first digit will be dropped due to space constraints on a small part, so the part number could be something like 1900-0602 etc (HP part numbers are in the xxxx-xxxx format).
It looks like 1900-xxxx part numbers are diodes, 1901-xxxx looks like discreet semiconductors like diodes and LED's etc. Integrated circuits and transistors seem to be 18xx-xxxx part numbers, with integrated circuits being around 182x-xxxx.

Looking at the passive components and stuff around them, maybe either opamp's, optocouplers or voltage regulators maybe?

The writing looks a lot like HP optocouplers. One has the RU safety marking, the other space for it.

[ZGoode]

Well, I ended up purchasing that copy of the 16064A manual on eBay.  Hopefully there is more information on it that will assist in the recreation efforts.  As soon as it arrives I will scan it at a high DPI and upload the PDF here (and probably to XDevs as well just so it is available in a few different places).

[TERRA Operative]

Scan at 600 dpi in colour and send the file my way somehow (google drive?)
I have a workflow set up on my PC to preserve quality at minimum filesize, so I can quickly and easily crunch down the filesize and send the resulting pdf back.

Also, did you manage to measure the precise size of the PCB (to the millimeter)?

[ZGoode]

I need to find something long enough to measure it accurately.  We have some 24" calipers on campus, but I need to wait for the summer break to be over to get back into that workshop.  My calipers only go up to 6"/150mm and this board is longer than 12" on one side.
If there are any color images I'll do a color scan, but it is most likely black and white and possibly already a photocopy.  I'll scan it at a minimum of 600DPI.

[TERRA Operative]

Cool. Even squinting at a standard ruler will be close enough.

FWIW, I find scanning manuals all in colour makes it easier to pull the text and diagrams from the page as any yellowing or other blemishes will end up blending in if scanned as grayscale. Just makes the image processing a bit easier for a cleaner result with less fuss.
I usually then crunch down to 16 'colour' grayscale indexed images as it results in much nicer images than the common black and white bitmap used in manual scans while not bloating the file size too much like true grayscale or colour images do.
(Colour pages are indexed with the appropriate colours for just the respective pages).
Not a big deal though. A tweak here and there in Photoshop can get a good result regardless.

[ZGoode]

I found an 11x17 scanner today so I could scan all the pages in one pass.  I've run it through acrobat to organize and clean it up, but if you want the raw scan I can upload that to oneDrive.  It's too big to upload here

[ch_scr]

Now, that helps with the two "mystery IC" U10 / U11.
While still nothing is found for their part number 1990-0557 / 1990-0602, the schematics include enough clues to find a fitting replacement.