On Sun, 20 Aug 2023, Chuck Guzis via cctalk wrote:
On 8/20/23 12:43, Glen Slick via cctalk wrote:
On Sun, Aug 20, 2023, 12:05 PM John H. Reinhardt via cctalk <
cctalk@classiccmp.org> wrote:
Hello all. I looking around for a Logic Analyzer for doing (mostly) DEC
QBus/UniBus stuff. Being the way I am I want something with enough lines
to handle the most of the signals so I'm guessing something with roughly
80-ish channels. I think that lets out all/most of the USB based LA. I've
looked around and it seems the the HP/Agilent 16700 series (16700B/16702B)
are probably what I want. I've also seen the 1670G which also seems quite
doable. I've seen a lot of posts at the EEVblog and it seems I missed
possibly the golden age of 16700 LA by a few years price-wise.
And to think that the old guys had an analogue lab scope and that was
about it. Personally, I find that setting up a logic analyzer to be a
last resort--all those damned wires to get right, then setting up capture...
I agree that the logic analyzer is a last resort, but when you need one
they're indispensable. I had a Telcon Zorba that had a number of problems
which I worked through with a scope and DMM (shorted diode and bad HOT on the
video board, bad 8275 CRT controller chip), before I had to break out the LA.
Along with the source code for the BIOS, I was able to use the LA to find a
bad 2N3904 in the interrupt chain for the floppy drives, and finally an 8254
Programmable Interval Timer with a dead counter. Without the LA, it would have
been a much longer repair process.
Mike Loewen mloe...@cpumagic.scol.pa.us
Old Technology http://q7.neurotica.com/Oldtech/
