Re: [LAD] [ot] rme fireface: weird balanced output measurements

On Saturday, February 18, 2012 08:29:11 AM Jörn Nettingsmeier did opine: Chuckle. Its caught me by surprise a couple of times. I've had a scope probe in one hand since around 1950. Its a very informative tool. Some of those usb gizmo's come with some truly useful software. If it can digitize to 16 bits (most of that stuff is only 8 bits), then the possibilities of doing some truly useful investigations under steady state signal excitation becomes available. Sadly, one of those that does 8 bits only, and claims to be able to an FTT, just doesn't have the bit depth to make that FFT's output of more than casual interest. My own scope, a Hitachi V1065, 100 mhz dual trace, is somewhat computerized, enough that it can measure p-p voltages, or time from point a to point b, and conversely a good estimate of the frequency by taking the reciprocal. Also a dual time base with what seems to be excellent time base stabilty. Still usable, despite its 100 mhz rating, at 185 mhz although not to claim it is still calibrated at nearly an octave above its ratings, I can at least chase through a ch 8 transmitters rf chain with it. Fairly light, I paid $1200 for it used when it was till available new for around 2G's about 21 years ago. I should think that a clone of it could be had from fleabay for 250-500 today. Expect to buy probes, I get decent ones rated for 200 mhz at a decent price from MPJones @ $40/copy. Personal opinion: Stay away from the low end stuff from even the major makers, its bound to be out of calibration AND non-repairable if its more than 10 years old. The majors simply do not support older stuff. Generally, Sencor does but it will spend the holidays in Sioux Falls too, HP will till they are out of custom parts. The only thing my old Hitachi has needed over the years was opened up and all the assembly screws snugged up and one missing one replaced, too many miles on too many vibrating airplanes in its history. Otherwise, at 20 some years, the tube is still factory bright and it Just Works(TM). The switches need some exercise occasionally but that's expected. I enjoy discussing things with Fons, I think in some sense we compliment each other, filling in the gaps so to speak. He has the theory better than I, and likely has at least 8 years more schooling than I, where I've been in the ditches making it work for almost 65 years. I have an 8th grade education, a GED, am a C.E.T., and have had what used to be a 1st phone for 50 years. But the commish threw that under the buss 30 years, so its not worth a lot in bragging rights today. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> The key elements in human thinking are not numbers but labels of fuzzy sets. -- L. Zadeh