At 09:24 PM 5/24/2006, Brooke Clarke wrote: >Hi John: > >I'm using the HP 5345A opt 11 now and really like it. When in the Time >Interval mode (cesium s/n 1227 1 MHz on start and cesium s/n 1013 1 MHz >on stop) you can turn the Gate Time knob up from "MIN" to say "1 SEC". >What this does is to accumulate the gate times for as many receptive >measurements as it takes to get to a total of 1 second, so the number of >measurements depends on the actual TI being measured. For example with >1 SEC gate time and a TI of about 574 ns it takes about 3 seconds of >clock time per measurement. The display is like 574.419,441 nano >seconds. That's 574 nano seconds and 419 pico seconds and 441 femto >seconds. If you set the gate time longer you get more digits. So at 10 >SEC you get 0.1 femto seconds resolution after a 30 second wait. Simply >fantastic! > >It counts to 500 MHz without any plugins unlike the HP 5245 that needs a >plugin to get to 500 MHz. But a drawback to the early models is that >the air filter is buried behind the FRONT panel and needs servicing >something like twice a year. This required taking the counter apart. >In later versions they removed the air filter. > >Although I can read HP-IB data in talk only mode, I haven't figured out >the secret of two way communication.
Hmm, I am not sure if I have any code left lying around for the thing. Possibly in RMB. I loved the 5345A, I lashed out as a young man and bought my first one for some horrendous amount of money in 1972 when they first came out. I remember the HP salesman coming to see me and he left me his demo unit. It was so pleased with it for what I was doing that I insisted he leave it until he could get me one for myself! Later I had occasion to purchase more of them and when we pensioned them of in favour of newer devices, I picked one of the newer ones with a 5355A plugin and a 5356B head for myself. In a fit of inexplicable madness and incipient senility I let the thing go last year for way too little money. >But the SR620 is still hands down my favorite TI counter. 16 digits with >a fixed weight on the positions is a really good layout. I would love to get hold of an SR620, I have never used one but the spec and manual certainly reads well. Now as a "tinkerer" I can't afford to lash out the dollars I once could. I have a Tektronix DC5010 - 3.25ns resolution as I recall. But to be honest I don't like it. It does the job I need it for right now, but as soon as I find a 5370B or an SR620 I can afford, it will go. >Have Fun, > >Brooke Clarke Oh I am always having fun of some sort! John Day _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
