DIYHiFi.org

JohnW,

Yeah, you bought something, I forget. Hi! Funny you should show up now, I just started using some ZXT849's in a switcher for ultrasonic sinewave heater supply for DHTs like 300B. These transistors are unbelievable. You guys have something great here. Not sure if it is my circuit, but so far they seem pretty picky with overdrive and storage time. Beta seems really high.

And the VacuTrace is full of Zetex transistors (free plug).

Oh yeah, my 7L5 works. HP makes better ones. But hey, it still works. And it goes super low in frequency.

jh

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Jim Hagerman

Anyone have experience with an HP/Agilent 54111D or can recommend something for around 1000-1500 usd? Thanks.

Chris

Hmm.. the Tek 2465B looks nice but I hear it has a common failure mode which is a hybrid IC that is no longer in production. Anyone know how common this failure is?

The HP 54111D has respectable specs: color screen, 500 repetitive / 250 mhz single shot, 8k memory, 1GS/s per channel but for mostly analog audio work I'm not sure if it would be worth the extra price.

Hi,
rather than specifying models that may never be available, what about a good audio specification that should be met. And maybe some nice to have super specs?

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regards
Andrew T.

I was looking for small, and capable of storing plots. I settled on a CL Systems PC DSG04. It is a 12 bit DSO. Mine is 10 Mhz 20MSPS analog, they have a 15Mhz 30MSPS analog. Both are 100 Mhz, 1 bit digital, with a signal generator, fft, and freq counter built in. It has five connectoions, 2 analog in, 2 digital in, and the signal generator out.
It fits in my laptop case, and replaces a trunk load of analog equipment. The ability to record and output plots is very nice.
I think that a used stack of H-P, or Tek gear would be a little cheaper though. Mine ran about 600.00 delivered with a USB adapter. The 15 Mhz analog model is closer to 675.00.
This is still reasonable for a 12 bit DSO. Someone recommended one to me that was 12,000.00. I do not have enough junk in the closet to fund one of those, even at todays ebay prices. These CL Systems are just a turntable or tube amp in price.

George

Hi Chris,

Dont buy the HP 54111D, its a horriable scope, limited sampling rate.... Cheap / early digital scopes are really poor - limited by there single shot speed (real sampling rate). I've got a couple of 8Gs scopes, and even these are poor compaired to a good old analogue scope for Pulse / PWM work...

Go for a later TEK 7000 (7904A) series or even better Tek 11302A.

John

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Hi-Fi??? "I may not be a psychiatrist but I know insanity when I see it - what ever happened to the normal old pervert who was content to sniff bicycle seats and collect women's shoes anyway?"

John,

Just picked myself up a Tek 7904A on ebay for a steal. Got the manual with it, along with the manual for the vertical amps, of which I got two 7A26, single timebase unit, 7B53A, and a 7A13 (guess why).

Now I'm worse off than ever before, because I have this kick ass scope sitting here with no probes, signal gen, nnnnnnnothing.

Anyway have you got any recommendations for what I should be after for these things? Cheaper the better, but I also dont' want to piss away money on some kind of junk. A spectrum analyzer would be a dream too, if you know of a decent one I should keep an eye out for.

Cheers,
Chris aka classd4sure