There are MANY semiconductor manufactures to this day that are still using the Tektronix 576 as their standard curve tracer. The data and information a properly calibrated 576 can deliver is invaluable for design and overall evaluation of semiconductors, vacuum tubes, resistors, capacitors, inductors and more. Most anything that tell's it's story with a V-I curve can be tested with the 576, up to 1500 volts, 20 Amps pulses and 200 Amps with the 176 fixture. It can measure down to nano amps. step generator in current voltage, inverted, DC bias offset on the steps and a lot more.
There is a independent test gear repair company in Silly Valley that offers flat rate repair for Tek 576 and even same day turn around.
http://www.equiptek.infoOne can tap in to the internals of the Tek 576 and route the X-Y signals to a DSO or similar digitizer and get the 576 data into digital format.
The Tektronix 576 was designed in the early-mid 1960's and has retained it's usefulness and market value to this day.
The later Tektronix-Sony 370 series cost more but offers a better interface for data. Functionally, the difference between the 576 with it's options and the 370 series is not much.
The Tek 576 is BIG heavy (about 70 pounds) and very serviceable. Not a hobby toy. No proper analog design lab is complete without one.
Berince
If you want a curve tracer, best get old Tektronix 575/576/577. These have enough power to even test power transistors to death. HP 4145/4155 is also nice if you can find it cheaply. 7CT1N is nice for small tranistors, if you already have 7k mainframe. Tek 370/371 if you have lots of money. Tek 571 is also sometimes found quite cheaply if lucky, goes up to 1A IIRC.
What would be really cool if someone would develope a modular USB curve trace controller to be conncted to GPIB capable DVMs that has several high resolution DAC channels to control PSUs with analog remote input.
Idea is to use DAC channels for remote control of cheap HP power supplies (E36xx series and HP 626X/627X series) Beefy 626X/627X in constant voltage mode to supply transistor CE. Small HP E36xx for base supply in constant current mode. Put some shunts on collector supply and use a cheap HP345x DVM to measure CE current (voltage over shunt).
Controller board sets base current on E36xx via DAC channel and sweeps CE voltage in small steps on 626X/627X PSU on second DAC channel while measuring CE current over GBIB connected DVM.
Improvement would be to use 3 GPIB multimeters to measure CE current and make precise regulation (e.g. PID controller on controller board) of base current and CE voltage.
That way you could get highly accurate transistor curves with nearly unlimited power in digital format, so no need to photograph the CRT to compare transistors. Also all parts are really cheap on ebay, in contrast to highly expensive Keithley 2400 sourcemeters.
Parts are also modular, nearly everybody has a PSU with analog remote input and some GPIB capable multimeter. So everything that is needed is a controller board for a few 10s of dollars with 2x 16bit DACs, a few HPIB connecors and isolated USB connector.
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