Nice video. I wonder if you could reliably measure the voltage that develops at a BJT's base when there is a voltage between collector and emitter (the voltage associated with ICEO). And also what you would measure with collector and emitter shorted.
This is a bit over my head, but I'm learning. I just subscribed. I'm focusing on '70s solid-state guitar Amp repair/design/improvement mods. Your videos are high quality and interesting. Thanks!
Hi. This is kind of a late comment, but since you have lots os videos featuring this electrometer, I imagine you own one, or at least have access to it. There is something that I have always been curious about, that I have never seen on any datasheet, and MAYBE you could try and measure: What order of magnitude would be the forward current on a regular silicon diode (like the 1n4007 for example) when forward biased with only 50 or 100mV? Is it absolute zero, or is it measurable?
While I haven't tried, but a diode's forward bias current is roughly Is*(e^(Vd/0.026) - 1), so at 50mV to 100mV, the forward current would be a few pico amp to a few nano amp and it's in theory measurable. I will definitely give it a try and see what the observed current is.
This is one of your most interesting videos I have seen. Very nice. Thanks! Might be nice to add links to manuals for the equipment, etc. in the notes. Just a little bonus. You have done some very nice videos. I appreciate your efforts.
Mark Zacharias I have the same fantastic meter. Noisier than my Keithley 195 and still drops a noise waveform a little bit. it's speed and resolution though make it a keeper for sure.
Hi, Kerry, the gold piece inside for my zero check is broken. Do you know where I can buy a replacement or any idea of repair/substitute? I use the “ Charge” mode only.
Is that the piece to the upper right of the the picture www.kerrywong.com/blog/wp-content/uploads/2015/02/Keithley614_INT3.jpg ? Unfortunately it's a custom piece, I believe is gold plated brass or something to that nature. The contact it self is soldered on outside of the low leakage section so I suppose you could replace it with a piece of copper bent to shape.
This thing would be good to try to find a short on a circuit board. BTW this is a good video but trying to see the resistor connections on the bread board is almost impossible.
I am getting into an experimental measurement of pyroelectric current. Came across this video in that context. Very informative video indeed. Thanks.
Nice video. I wonder if you could reliably measure the voltage that develops at a BJT's base when there is a voltage between collector and emitter (the voltage associated with ICEO).
And also what you would measure with collector and emitter shorted.
Very good and instructive video!
This is a bit over my head, but I'm learning. I just subscribed. I'm focusing on '70s solid-state guitar Amp repair/design/improvement mods. Your videos are high quality and interesting. Thanks!
Hi. This is kind of a late comment, but since you have lots os videos featuring this electrometer, I imagine you own one, or at least have access to it.
There is something that I have always been curious about, that I have never seen on any datasheet, and MAYBE you could try and measure: What order of magnitude would be the forward current on a regular silicon diode (like the 1n4007 for example) when forward biased with only 50 or 100mV? Is it absolute zero, or is it measurable?
While I haven't tried, but a diode's forward bias current is roughly Is*(e^(Vd/0.026) - 1), so at 50mV to 100mV, the forward current would be a few pico amp to a few nano amp and it's in theory measurable. I will definitely give it a try and see what the observed current is.
I just post a video on this subject. Enjoy!
This is one of your most interesting videos I have seen. Very nice. Thanks! Might be nice to add links to manuals for the equipment, etc. in the notes. Just a little bonus. You have done some very nice videos. I appreciate your efforts.
Thanks! I do have the links to all the equipment on my website, just not on my youtube channel.
On my Fluke 8840A the input impedance is in the giga-ohm range up to the 20 volt range. Useful feature.
Mark Zacharias I have the same fantastic meter. Noisier than my Keithley 195 and still drops a noise waveform a little bit. it's speed and resolution though make it a keeper for sure.
hello...can you please tell me how to use keithley 617 electrometer..i want to measure current by keeping voltage fixed.
Hi, Kerry, the gold piece inside for my zero check is broken. Do you know where I can buy a replacement or any idea of repair/substitute? I use the “ Charge” mode only.
Is that the piece to the upper right of the the picture www.kerrywong.com/blog/wp-content/uploads/2015/02/Keithley614_INT3.jpg ?
Unfortunately it's a custom piece, I believe is gold plated brass or something to that nature. The contact it self is soldered on outside of the low leakage section so I suppose you could replace it with a piece of copper bent to shape.
@@KerryWongBlog Thank you. I soldered the pieces together. It works like new.
good but any less than usd 7k option now or no
Thank you very much
Great video thanks
+Ami Khimji You are welcome. Glad you liked it.
Very use full information Thanks - Llloyd - DigiTek
This thing would be good to try to find a short on a circuit board. BTW this is a good video but trying to see the resistor connections on the bread board is almost impossible.
"When to use an electrometer?" - "When you're using REALLY big breadboards".
only dc huh