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.