So, for example, the 2N3055 should be tested at Ic up to 15A and Ib up to 7A. Is that right?Well you need more current, 12 mA is a very small current, so for power amps you need to test transistors at higher currents closer to their operating conditions.
15A is the limit for the 2N3055, thats a bit extreme, also beta droop is worse at higher currents so it is not best to work transistors at very high currents, but perhaps between 1A to 3.5A like this curve tracer allows is more than enough.
The quantity on ebay has been updated.
Locky_z 2019 Curve tracer with new component | eBay
Locky_z 2019 Curve tracer | eBay
Locky_z 2019 Curve tracer with new component | eBay
Locky_z 2019 Curve tracer | eBay
This listing was ended by the seller because there was an error in the listing.
1. click on the link in post #264 above
2. click on "see original listing"
3. click on "locky_z" right below "seller information"
4. click on "Items for sale (2)"
5. you get these two error-free listings
Locky_z 2019 Curve tracer | eBay
Locky_z 2019 Curve tracer with new component | eBay
+
2. click on "see original listing"
3. click on "locky_z" right below "seller information"
4. click on "Items for sale (2)"
5. you get these two error-free listings
Locky_z 2019 Curve tracer | eBay
Locky_z 2019 Curve tracer with new component | eBay
+
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I'm also say the same.One of my best buy, I used this great curve tracer all the time. A must buy for anyone interested in matching. Very recommended...
I've had very few problems so far, most related to serial to USB converter: it chooses a COMM port number ramdomly sometimes, but is a know problem with Windows, and very few problem with measurement, with some P-MOSFET. So far I've measured sucessfully hundreds of devices, including a lot of germanium devices, Gallium Arsenide MESFET, and tubes (thyratron as "zener" connection, rectifier and signal valve diodes), and of course, "normal" Si devices (most vintage)
LM317 regulated 36-40V to 24V, Its voltage drop is only 16V, the LM317 can be used here without any problem.
The maximum supply voltage is determined by the op amps, which use the supply voltage directly.
The maximum supply voltage is determined by the op amps, which use the supply voltage directly.
Sorry to go further but I find this product interesting 😉 Datasheet state 40V is maximum rating. Not normal operational condition.LM317 regulated 36-40V to 24V, Its voltage drop is only 16V, the LM317 can be used here without any problem.
The maximum supply voltage is determined by the op amps, which use the supply voltage directly.
Changing chip for more SOA, will invalid garantee ?
You should check the LM317 data sheet again, it says that the Input reference differential voltage should not exceed 40V, not that the maximum input voltage should not be greater than 40V. There is even a small formula Vi-Vo, that means that the difference between the input and the output should not exceed 40V, meaning that you can input say 100V, as long as the output is no lower than 60V. So yeah, locky_z was right by suggesting that the standard LM317 is a good choice since there is only a 16V input to output differential in the circuit. The HV version that you mention has a 57V input reference differential voltage spec, which is of course not needed here.
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The curve tracer maximum supply voltage is determined by the op amps, which use the supply voltage directly.
In curve tracer, there two type op amp, one type is follower, one type is single power supply op amp.
The follower opamp need low Vos(<2mV) and low Ibias(<10nA), and unit gain stability, and Vicomm(or Input Voltage Range) between Vee+2V ~ Vcc-2V.
The single power supply op amp must single power supply op amp, and output voltage is from 1 to Vcc-2V.
In curve tracer, there two type op amp, one type is follower, one type is single power supply op amp.
The follower opamp need low Vos(<2mV) and low Ibias(<10nA), and unit gain stability, and Vicomm(or Input Voltage Range) between Vee+2V ~ Vcc-2V.
The single power supply op amp must single power supply op amp, and output voltage is from 1 to Vcc-2V.



A 30V toroidal laying on shelf will do the job for 40V regulated supply.
The more I read about this curve tracer, the more I find it attractive !
You should bite the bullet and buy it, I did but I am still waiting for mine to arrive from China, Covid doesn't help either, but I'm stoked to try it out. I bought the disassembled version and saved a few bucks, I just hope the longevity of the parts is ok.
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I am so glad this curve tracer is available again, will pick up one in a few months. Have multiple devices I need to match 🙂
A recent application of the Locky-Z curve tracer, tracing the curves of a circuit on a protoboard, rather than an individual semiconductor device: post #34
In this case the circuit is a 2-terminal constant current source. I used the presupplied NPN VCE-IC test setup, connecting current_source_plus to the "Collector" terminal and connecting current_source_minus to the "Emitter" terminal.
Cascode was a J112 NJFET connected in series between the CCS and the curve tracer, with negative feedback to the source.
In this case the circuit is a 2-terminal constant current source. I used the presupplied NPN VCE-IC test setup, connecting current_source_plus to the "Collector" terminal and connecting current_source_minus to the "Emitter" terminal.
Cascode was a J112 NJFET connected in series between the CCS and the curve tracer, with negative feedback to the source.
I have translated the Chinese phrases inside ads7871_v3s.PRE so that the various tests offered can be comprehensible to English lanugage users.
I have also translated the Chinese curve tracer diagnostic and troubleshooting manual into English.
Both have been submitted to locky_z official GitHub repository so they can be merged into the main branch and enjoyed by all English language users.
I purchased my curve tracer from locky_z last week, and I have to say that the device and software is the work of true genius! I absolutely LOVE that thing, it is FANTASTIC!
I have also translated the Chinese curve tracer diagnostic and troubleshooting manual into English.
Both have been submitted to locky_z official GitHub repository so they can be merged into the main branch and enjoyed by all English language users.
I purchased my curve tracer from locky_z last week, and I have to say that the device and software is the work of true genius! I absolutely LOVE that thing, it is FANTASTIC!
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