HP1630D Logic Analyzer repair

[millerb]

I just a 1630D from a user on the forum and it worked great except for inability to sample under 500ns. Inside the unit there are several boards in a card cage, with all of the logic and cpu cards underneath the power supply card, which makes them inaccessible. The bus plane the cards plug into is mounted vertically at the front of the device. There is a bus connector at the top mounted parallel to the top cover of the unit. So, if you need to trace a problem on a board, you can pull it out of the card cage and plug it into the service port on the top side of the machine. Neat!

The problem with this machine was a stuck 200MHz oscillator circuit on the master timing board. I followed the procedure in the service manual and got it working again. (Just had to adjust a variable capacitor). Two of the flip chip ICs on the timing master board get ridiculously hot and have to be kept cool. I put a fan on a stack of junk on a char to keep air rolling over the heat sinks. I also attached a sensor on one of them to monitor the temperature while I carried out the repair.

Here's a link to the service manual: http://bitsavers.informatik.uni-stuttgart.de/pdf/hp/te/01630-90917_1630_Service_Apr88.pdf

Not a particularly useful post, nor an interesting repair but I think the attention to detail HP put into the design of this unit is nice.

[WBB]

Very nice indeed! It really is amazing how far companies would go to make the equipment serviceable. Far cry from the cheap crap these days. Service manual? Ha, the schematics for a lot of this crap probably doesn't make it off the white board!

[SeanB]

Now that is a unit designed for the repair technician, having the foresight to put in a built in extender card for the unit.

[marshallh]

Glad you are able to use it. I had no idea that there was an issue like that.
By the time I had it set up where I could use it, it wasnt useful to me.

[duskglow]

Are the hot flip flops by design or an indicator of another problem?

[millerb]

Are the hot flip flops by design or an indicator of another problem?

They seem to run hot by design. There's a warning on the PCB to keep air on them and more warnings in the service manual to keep them cool when messing with the board. Definitely not an eco friendly unit. Hot air blasts out of the side of the machine, even the logic pods get warm.

[millerb]

Glad you are able to use it. I had no idea that there was an issue like that.
By the time I had it set up where I could use it, it wasnt useful to me.

np. And thanks again for the machine! It's perfect for what I'm doing. Also had fun digging around in the guts of the machine. Remarkably clean for something this old.

(now to get back to solving my SPI glitching problem)

[amyk]

Those are ECL gate arrays, they take a lot of power (and are very fast too.)