HP 1631d logic analyzer.

[Dan Moos]

Picked this thing up on eBay for 60 bucks. Partly because having 43 state channels it's pretty nice for the 6502 homebrew computer I'm working on. Mostly because it's old and cool.

But dang, this thing is huge!

Seems in working order so far. Anyone have any experience with this model?

Notice in the pic with probe pods, one has an adapter that breaks out individual wires. Out of five included pods, only two had this adapter. I'm not even sure what that adapter is called so I can hunt down some more. Any ideas?

Sent from my E6830 using Tapatalk

[gslick]

Picked this thing up on eBay for 60 bucks. Partly because having 43 state channels it's pretty nice for the 6502 homebrew computer I'm working on. Mostly because it's old and cool.

But dang, this thing is huge!

Seems in working order so far. Anyone have any experience with this model?

Huge? It's small and light compared to a 16500 series mainframe.

I picked up a 1630D (same thing as a 1631D minus the analog channels) because it's old, and maybe sort of cool in some way as an example of early logic analyzers to compare against the more modern ones I have.

My 1630D originally came with HP-IL mass storage device firmware. I updated it with HP-IB mass storage device firmware by programming these binary files into eight 27128 EPROMs to replace those on the CPU board.

HP_1630A_D_1631A_D_Logic_Analyzer_EPROM_14-Oct-1985-HP_1630A-D_1631A-D_ROMs.zip
found here: http://www.ko4bb.com

[Dan Moos]

any idea what this thing would have cost in its day?

[stj]

that will be in the sales sheet - it's probably online.

[Lorenzo_1]

I have a 1630D that's had a couple of problems. When I first got it the display would go haywire after about an hour's use and display seemingly random signals.  Removing, cleaning and reseating all the boards fixed that. Second problem was disappearance of the whole waveform graphics display area while the text displays showed up fine. So I could use it only in LIST mode. What I did find neat was that I could install the faulty board upright in the maintenance/service slot and use the logic analyser to debug itself - just took lots of tedious analysing 1s and 0s in LIST mode.   Suspected a character ROM fault but it turned out to be a counter that wouldn't count.Easily replaced.  It seems to be a pretty repairable machine. Been working fine ever since. 

[Dan Moos]

I have a 1630D that's had a couple of problems. When I first got it the display would go haywire after about an hour's use and display seemingly random signals.  Removing, cleaning and reseating all the boards fixed that. Second problem was disappearance of the whole waveform graphics display area while the text displays showed up fine. So I could use it only in LIST mode. What I did find neat was that I could install the faulty board upright in the maintenance/service slot and use the logic analyser to debug itself - just took lots of tedious analysing 1s and 0s in LIST mode.   Suspected a character ROM fault but it turned out to be a counter that wouldn't count.Easily replaced.  It seems to be a pretty repairable machine. Been working fine ever since.

So far, I've had the thing running for a few hours with no faults that I can find. I have it reading the data bus on my homebrew computer. The computer spends it's idle time in a simple NOP loop, and the LIST view shows the exactly correct HEX data it should.

I need to figure out how to do pattern triggering, so I can see other stuff. Right now, when I do other stuff on the computer, its gone before I can hit stop, so all I ever see is my idle loop. HP still has a scan of the manual on their site, so I've got a little reading to do.

Sent from my E6830 using Tapatalk

[gslick]

any idea what this thing would have cost in its day?

According to this page:
http://www.azurelectronics.com/HP%201630D%20Logic%20Analyser.htm

In 1987, the 1630A cost $8,600, the 1630D $10,630, the 1630G $12,100. The upgrade kit from 1630A-D to G cost $3,450.

[Dan Moos]

Well, I got it for 60 bucks. And its probably one of the lower tech instruments on my bench (although I already see uses for it that aren't as convenient on my USB analyzer. 43 channels is pretty cool. Obviously, the memory is vastly smaller, but I don't see that being an issue with what I will be using it for. Kinda fun analyzing a homebrew 6502 computer with a piece of equipment that was of the same era.

As an aside, its the crappiest oscilloscope I have (not counting an old tube driven heathkit I have for the fun of it). Even with all the "processing" turned of, it's update rate is pathetic. You have to go into another screen, and specifically input your volts per division!

That's alright. The scope part of it was not why I bought it. Still, its difficult to see why one would have paid extra for the 1631 just for the scope option. I have an analog Tektronix 2213 of similar vintage that is way more useful as far as I can see. Obviously my modern DSOs make both of those scopes look like toys. Great time to be in this hobby!

[meriororen]

Logic analyzer of that era here is pretty cheap. Saw that on yahoo auction Japan for 1¥ (less than a penny), and ended with no bid. With 1600¥ shipping it's still feel expensive.


Sent from my iPhone using Tapatalk

[helius]

The selling point for the LA+scope instruments was logic based triggering for the scope capture. This was better than using a 2465A with the word recognizer probe because it was infinitely more flexible.

The adapter on the end of the pod is called a general purpose probe housing. It has a compensation network inside.
*The housings on the 1631 appear to not have any compensation network. They are called "clip assemblies" in the manual.

[harrimansat]

6809 Inverse assembler for hp1630

[TK]

Inverse Assembler for 6502 that I found online.  I tried it on 16702B, 16500C, 16500B.  It should work on 1631D but I am not sure.

[MarkL]

The adapter on the end of the pod is called a general purpose probe housing. It has a compensation network inside.
*The housings on the 1631 appear to not have any compensation network. They are called "clip assemblies" in the manual.

Correct; they don't.  They are just wires, so it's possible to make your own leads if you can find a mating pin socket.  Note that the pins are NOT square (0.030" x 0.060").

The compensation network is on the hybrid in the housing; photo below if anyone is curious.

[helius]

Thanks for the picture. That's a huge hybrid!

[MarkL]

AND it's only 0.045" thick!  Very thin considering it's size of 2" x 3".

They sure loved ceramic hybrids back then.  They're in everything.