Bob Camp wrote: > Hi > > Other than the normal issues with blown inputs, the 5334 is a pretty > rugged > beast. It's not got a whole lot of crazy stuff inside it. It does have > some > custom IC's and firmware.
Actually, it has crazy stuff IMHO. The controller is broken up into three separate microprocessors because of various historical accidents. The custom IC's are somewhat "crazy" as well in that the circuits could have been replaced with OTS IC's, which is what I did in the 5334B. I unfortunately inherited the 3 uP's and couldn't design them out. The power supply in the 5334A was also weird in that the oven warmup current would pull it way down in voltage, below its spec. The counter accidentally worked anyway, but if you were troubleshooting, you might think it was broken. The PC board had a weird single point ground, instead of a ground plane as in the 5334B. Rick Karlquist N6RK Project Manager HP 5334B, circa 1987 _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.