XY mode
Hi Laurence
There are 2 options for XY mode with this mainframe.
1, if you have 2 7Axx plugins then you plug one of them into the right hand compartment, this give full control of the X amplifier settings.
2, most 7Bxx plugins have a external amplifier input, it usually connects via the Ext trig connector, but the controls set it up for ext amplifier, check out the 7Bxx manual for details,
Cheers
Paul
Hi Laurence
There are 2 options for XY mode with this mainframe.
1, if you have 2 7Axx plugins then you plug one of them into the right hand compartment, this give full control of the X amplifier settings.
2, most 7Bxx plugins have a external amplifier input, it usually connects via the Ext trig connector, but the controls set it up for ext amplifier, check out the 7Bxx manual for details,
Cheers
Paul
Hello Paul thank you for your reply....let me please get this straight...so i remove the time base (its in the very right side compartment) and then install and amplifier there? and put the other amplifier next to it?
Lawrence
)
Hi,
I need some help,I have a Heath kit IT3121 curve tracer I built long ago,I can tests FETS with no problems,Can it be modded to read the irf240's and the like ,I am thinking it needs more power to do this,maybe 30 volts @5amps ,But I am not sure how to wire/replace what needs done,I think D to S needs about 30 v,But not sure what to do for the gate,Would some one point the way or recommend a site!
Thanks,
NS
I need some help,I have a Heath kit IT3121 curve tracer I built long ago,I can tests FETS with no problems,Can it be modded to read the irf240's and the like ,I am thinking it needs more power to do this,maybe 30 volts @5amps ,But I am not sure how to wire/replace what needs done,I think D to S needs about 30 v,But not sure what to do for the gate,Would some one point the way or recommend a site!
Thanks,
NS
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The MOSFETs will allow a lot of current when they are biased into full conduction -- this is why Tektronix sold a separate fixture (176) for testing them. Make sure to heat sink the device during testing.
Hi Jackinnj,
Thanks ,I have a heat sink for them ,when I connect DGS it doesn't read,so I am thinking not enough current flowing to turn it on, that converter is for a Tek,so does anyone know how it is wired up for a IT3121 and what circuit has to be changed to? I'll look for the manual for TEK176 maybe it will show how it's wired,
Thanks,
NS
NS
Thanks ,I have a heat sink for them ,when I connect DGS it doesn't read,so I am thinking not enough current flowing to turn it on, that converter is for a Tek,so does anyone know how it is wired up for a IT3121 and what circuit has to be changed to? I'll look for the manual for TEK176 maybe it will show how it's wired,
Thanks,
NS
NS
I've only seen one trade on EBay and it was about $600. There's one perpetually offered for just under a kilo-buck.
I had thought of Ron Dekker's "uTracer" but it's limited to 200mA at the present time. The uTracer pulses the voltage to the DUT. I am guessing as well that the high capacitance of a MOSFET is a difficulty which must be overcome.
Hi Guys,
I found a tek 576 on ebay It's sold as seller refurbished,,,FREE shipping FOR $10 dollars,lol,It also stated it was for evaluation,so I don't know what's not working and I hope I can repair it,
Tektronix Curve Tracer 577 576 Repair Evaluation Only | eBay
NS
IT-1121 testing MOSFETs
Is anyone familiar with the IT-1121 Curve Tracer ? To test FETs it reverses the polarity of the step voltages. This is fine for JFETs and depletion type MOSFETs but not for the enhancement type. Damon Hill complained about this. There is a reversal switch SW 9 after IC 3. Would it work to insert a switch between SW 9 and SW 3 to choose between reversal and non-reversal ?
Is anyone familiar with the IT-1121 Curve Tracer ? To test FETs it reverses the polarity of the step voltages. This is fine for JFETs and depletion type MOSFETs but not for the enhancement type. Damon Hill complained about this. There is a reversal switch SW 9 after IC 3. Would it work to insert a switch between SW 9 and SW 3 to choose between reversal and non-reversal ?
have a problem measuring hfe for NPN and PNP bjts. on the DUT detect it tells me something and if I try to trace the curve something else.
The funny thing is that one hfe given by the curve goes out of spec for a specific part, which is suggesting that the measurement is foo-bar.
I am trying to do static measurement, but it is not working at all, don't get any result. I tried to plug the BJT on the XYZ port as well as on the right BCE port.
Is there some setting I need to do in order to get proper hfe?
Thanks in advance for your advice.
The funny thing is that one hfe given by the curve goes out of spec for a specific part, which is suggesting that the measurement is foo-bar.
I am trying to do static measurement, but it is not working at all, don't get any result. I tried to plug the BJT on the XYZ port as well as on the right BCE port.
Is there some setting I need to do in order to get proper hfe?
Thanks in advance for your advice.
Hi Stefanoo ! To check this Heath curve tracer (without a transistor) I connected my DVM between banana jacks E and C. Turning the sweep voltage all the way up I got 32 VDC on the 0-40 V Sweep Range. Also, I looked at the staircases they show on the schematic. Connecting my o-scope to the yellow wire on the Norm-Cal switch inside the unit I got a staircase going upwards as expected when turning up Steps/Family. However, I didn´t get the downwards staircase that should appear when you connect to banana jack B. There is a catch: you have to choose a higher Step Range than suggested by the schematic (1Volt works fine). I don´t know if this is of any help. Measuring beta with this instrument would require some calculus from my side which I try to avoid at all cost. Instead I use other instruments to read beta on a meter. A warning to everyone: don´t try the switch I talked about previously unless you know what you are doing. I can´t make it work as intended.
Finally I got my polarity switch fixed. Sure enough, I´d made a wiring error. So, is it worth the effort ? Not necessarily, testing a power MOSFET showed just one line (even at 1 V/step). Probably because I can´t add an offset to these steps. Stefanoo ? I´m new to this instrument. Bought it at a hamfest. I got some feel for it by doing the exercise from page 57. I took care not to use a high gain transistor. But first I did the Oscilloscope Calibration which is more of a check-up. The recommended scope settings worked fine and if so should be used permanently. I reckon one is then free to juggle the horizontal and vertical sensitivity on the instrument for best picture. I also did the Offset Adjustment and yes it had gone off mark.
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