Because they're more affordable I'm considering a used TEK P6046. Do these accept only proprietary extensions for it's probing pins?
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I would avoid one so old differential probe.
You may found my own story as interesting, if you are willing paying 1/3 of the price of a new.
My very first Differential Probe, PINTEK PD-50 50MHz 6.5KV (pictures)
You may found my own story as interesting, if you are willing paying 1/3 of the price of a new.
My very first Differential Probe, PINTEK PD-50 50MHz 6.5KV (pictures)
I am using one, with a matching amplifier box that goes between the probe and the scope. There's an external 100VDC power supply for the box which also functions as an attenuator.
So presumably you can build your own power supply and amplifier/attenuator box if you have all the data and schematics, not sure you want to though.
Jan
So presumably you can build your own power supply and amplifier/attenuator box if you have all the data and schematics, not sure you want to though.
Jan
Not to be so defiant but what could be wrong with an old differential probe as long as it takes accurate measurements? It reminds me of a line by Woody Allen "it must be one of those 'new' doors .." or "one of those old differential probes from Tek 🙂" Isn't the result what matters? It does however feel cumbersome to use a separate power amplifier and PSU just to use this ancient instrument from Tek which no longer has support and parts probably no longer exist. I have few relics from Tek from the 70's and 80's and they all work quite well. They still perform everything documented in their user manuals which is commendable.
Are you saying that you are ready to spend over this old item about 150$ for a calibration certificate in 2014 ?
From the other hand did you take under consideration the accuracy percentage of the input of your Oscilloscope in comparison with this probe?
My fresh Oscilloscope comes with 2% accuracy and the probe that I got is close to that, if I was using an ancient 5-8% probe I would sabotage the quality of measurements of my own fresh Oscilloscope.
Think again.
I have two P6046s too. Many applications (and for audio there are many such) don't require good absolute accuracy from a scope measurement, let alone certificated calibration.
That's surely a good tool if you need high CM ranges (e.g. switched power supply measurements), but it's not particularly suitable for high-frequency work (non-coaxial connectors).
Samuel
That's surely a good tool if you need high CM ranges (e.g. switched power supply measurements), but it's not particularly suitable for high-frequency work (non-coaxial connectors).
Samuel
I have not see any such a probe with coaxial connectors as input, BNC connectors are low voltage items.
Low volt / High bandwidth probes comes with fixed tweezers and they worth around 3000$
Low volt / High bandwidth probes comes with fixed tweezers and they worth around 3000$
This is very helpful thank you. My scope is a Tek 2430A digital 150 MHz. When in production they sold for around $7K. It was discontinued in 2000, has input impedance of 1 MOhms or 50 Ohms. I looked in the spec-sheet but didn't see anything about input accuracy %, do you know what criteria is used to calculate this figure?
Tek P6046 probe is from the early 2000's. My interest is in learning about audio, low power amplifiers, power supplies and speaker cross-overs. The P6046 I was considering was around $75 and working, not sure about it's calibration status.
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The most important cal point in a diff probe is the CMR. You'd want zero output if you short the two inputs and drive them with a signal. This is something you can easily cal yourself without sophisticated equipment.
jan
With out even looking an specification datasheet I am aware that the best analog Oscilloscope it can only come close to 5% when has spot-on calibration.
Due the change in the condition of it components one analog Oscilloscope needs not just calibration check (which is a simple report on paper), but an general inspection regarding electronics parts and mechanical controls (switches, potentiometer, button etc) Every two years.
From the other hand any analog Oscilloscope as long it XY beams circuitry is healthy it can be used so to review waveforms, but not to measure them or to analyze them.
What it bothers me for this old TEK setup (probe + Scope), is the sensitivity in low volts / mV Range.
In case that shown as insensitive below the one volt or half volt, it would be useless for measuring an preamplifier, which their output is at 150mV or 300mV or even much - much less, when you need to measure turntable head preamplifier.
The Tek 2430 is a digital scope and speced for basic 2% vertical accuracy. The good analog scopes (e.g. Tek 2465) are speced for 2% basic vertical accuracy too.
Samuel
If you have such data available feel free to discover and the accuracy specifications of that specific probe, because in the end this will do all the work.
Essentially all Tek manuals of relevance are freely available and easy to find.
The P6046 is speced in differnt ways, depending on the used oscilloscope vertical amplifier/interfacing. Between 2% and 4%.
Samuel
The P6046 is speced in differnt ways, depending on the used oscilloscope vertical amplifier/interfacing. Between 2% and 4%.
Samuel
The first thing to consider is whether you actually need a differential probe. Most things can be done with standard 1x/10x probes and occasional use of two oscilloscope channels for balanced signals/differential probing. What's your incentive for a differential probe?
Samuel
Do I need a differential probe?
damage would hopefully be limited to circuit under test leaving my ancient 2430A unharmed.
So after my confession would you say "my methods are unsound?"
That was my feeble attempt doing my Brando impression of Colonel Kurtz. Is it safe to conclude my insistence on using a differential probe is equivalent to driving to Wall-Mart in a Porsche?
I was told by far more intelligent beings than myself differential probes are isolated from mains ground. When testing a power amplifier board with an input signal from a frequency generator operating on mains-ground, using 1x/10x probes, the scope and frequency generator would be sharing AC ground. In this scenario it seems a differential probe isolated from AC ground would not pick up shared noise from AC ground and provide more accurate measurements from circuit under test. Also if the probe's ground accidentally touched a + rail
damage would hopefully be limited to circuit under test leaving my ancient 2430A unharmed. So after my confession would you say "my methods are unsound?"
That was my feeble attempt doing my Brando impression of Colonel Kurtz. Is it safe to conclude my insistence on using a differential probe is equivalent to driving to Wall-Mart in a Porsche?
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