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https://www.google.de/url?sa=t&source=web&rct=j&url=http://www.educator-resources.com/pdf/Teacher%2520Tort%2520Liability.pdf&ved=2ahUKEwjl68eNuY3ZAhVRJewKHQvABooQFjAAegQIERAB&usg=AOvVaw2mJgi39wy1AwntLLTlEXkD
Not sure why you are bringing religion into this. The document you referenced is about church schools. I am a professor at a public institution.
You might make it on national TV? I wonder if rigol is happy if their product is featured in such a case?
But since there is always a slim chance, that one of the kids has a heart problem, so your zapping idea might be this kids terminal experience.
Instead I would go to your boss and ask if (s)he is ok, if you hit the kids with a whip. That seems less dangerous to me.
But since you brought religion into this...... A pastor was un the pulput and admitted having forced a minor to have sexul relations with him. (It was one of his bible study studnets.) What did the congeration do? Stood up and applauded for his honesty. Wait a minute he ruined the life of a young women and committed a felony. I have to ask why was he not arrested? And you are worred about a student getting zapped and suing the school.
Again I will ask in your career working with electrity have you ever been zapped? Did that runin you for life?
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Again I will ask in your career working with electrity have you ever been zapped? Did that runin you for life?
That isn't the point!
Johnny: "Hey dad, I got an electric shock in school today!"
Dad: "That's great! We just won the California lottery! Maybe you should lie down and practice moaning while I call a lawyer. Roll your eyes and twitch a bit!"
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If this thread doesn't stay on topic then I'll lock it and/or delete all the off-topic stuff.
Come on, a thread on which scope get ends up at religion is going too far. -
I purchased the Rigol scope (received it on Friday) and very pleased so far. Screen is larger than what I expected. Screen and text on the screen is very readable. If one reads this post you will see I did consider other brands of scopes and you will see my reasoning for not purchasing those other brand. For $350 (USD) I think I got an excellent value.
Bottom line, if you are in the market for a new scope on a limited budget BUY the Rigol. The other piece of test equipment I purchased was a two channel logging DMM. This thing is an incredible value at $105 (USD) Mooshimeter with Bluetooth. This device uses your smartphone or iPad for the display which has it's advantages. I have 3 Fluke meters, and a couple cheap ones but they don't have a data logging. This one does and like the Rigol scope I would give both of these products 5 stars. They are easy to use, well built and will be used in my lab and classrooms for years to come.
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Note the CAT rating printed on the front:
I assume you'll be teaching CAT ratings in your electronics class, given that you're messing around with bare AC mains wires, etc. as part of the curriculum.
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Quick question about the Rigol DS-1054Z since I don't know anything about oscilloscopes
Batterfly a good deal for the below items for 440 eur, and since I'm in the market to upgrade all of my equipment this sounds good!
Rigol DS1054Z
Extech EX330
HAKKO FX-888D
Is the DS1054Z able to act as a frequency counter? I need to tune a few synths VCO's I built and thus need to measure 400-500hz. -
Is the DS1054Z able to act as a frequency counter?
Yes.I need to tune a few synths VCO's I built and thus need to measure 400-500hz.
No problem.
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A real frequency counter has a much higher resolution than an oscilloscope so depending on the requirements the answer may also be 'no'.Is the DS1054Z able to act as a frequency counter?
Yes. -
Note the CAT rating printed on the front:
I assume you'll be teaching CAT ratings in your electronics class, given that you're messing around with bare AC mains wires, etc. as part of the curriculum.
So with 10x probes it's duh... 10 Megohm /130pf 3000 volt RMS CAT 10 ?
No IPxx rating on the Rigol ?
Pool party trippy waveform DSO demos accompanied by trance moozik on schoolie nights are out then...
BS aside, not a good idea to go straight up mains probing with stupdents around,
especially if no one's wearing safety eyewear
Eyewear and gloves is a MUST for any mains work, end of story
Typed here by a VERY LUCKY mis-informed overconfident survivor
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I need to tune a few synths VCO's I built and thus need to measure 400-500hz.
No problem.
You did not even ask how accurate it need be and what is needed resolution/accuracy for this tuning anmd then you professionally answer: No Problem.
Perhaps no problem but this you or onyone else do not know because original question do not include enough definitions.
So lets first ask more questions before start giving answers.
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So with 10x probes it's duh... 10 Megohm /130pf 3000 volt RMS CAT 10 ?
Do you know students? There's always one.
( Actually that's maybe the best possible outcome here. The shiny new Rigol gets zapped instead of a student. Lesson learned?
)Eyewear and gloves is a MUST for any mains work, end of story
Ear protection is good, too. Electricity can go bang.
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Is the DS1054Z able to act as a frequency counter?
Yes.I need to tune a few synths VCO's I built and thus need to measure 400-500hz.
No problem.
A real frequency counter has a much higher resolution than an oscilloscope so depending on the requirements the answer may also be 'no'.Is the DS1054Z able to act as a frequency counter?
Yes.I need to tune a few synths VCO's I built and thus need to measure 400-500hz.
No problem.
You did not even ask how accurate it need be and what is needed resolution/accuracy for this tuning anmd then you professionally answer: No Problem.
Perhaps no problem but this you or onyone else do not know because original question do not include enough definitions.
So lets first ask more questions before start giving answers.
Thanks for the replies!
I guess my questions maybe doesnt contain all relevant information since I'm really new to all of this but a resolution of 3 decimal points should be good enough.
I need to be able to octave trackck the VCO.
For example
C0 Note
1v Octave V: 0.0833
Expo Output: 0.1655
Frequency: 65.4078
A2 Note
1v Octave V: 2.8333
Expo Output: 1.1136
Frequency: 440.0092
Tuning instructions for another synth:
The 1V/Oct on each board should be trimmed to 1V/oct. Input a 0-4V signal in the tune input (A nice to have if the rigol can do this, otherwise I can do it from a different synth). Check point 1 with a frequency counter. Adjust so that you have a frequency doubling from 0-1V, from 2-3V, and 3-4V.
The trimmer on both board two and three is for the VCO tune. Hook a frequency counter to point 1 and adjust the tune slider for 440Hz. Then measure point 2 and adjust the trimmer for exactly 450Hz. Repeat on next board. -
I guess my questions maybe doesnt contain all relevant information since I'm really new to all of this but a resolution of 3 decimal points should be good enough.
I need to be able to octave trackck the VCO.
For example
C0 Note
1v Octave V: 0.0833
Expo Output: 0.1655
Frequency: 65.4078
A2 Note
1v Octave V: 2.8333
Expo Output: 1.1136
Frequency: 440.0092
Tuning instructions for another synth:
The 1V/Oct on each board should be trimmed to 1V/oct. Input a 0-4V signal in the tune input (A nice to have if the rigol can do this, otherwise I can do it from a different synth). Check point 1 with a frequency counter. Adjust so that you have a frequency doubling from 0-1V, from 2-3V, and 3-4V.
The trimmer on both board two and three is for the VCO tune. Hook a frequency counter to point 1 and adjust the tune slider for 440Hz. Then measure point 2 and adjust the trimmer for exactly 450Hz. Repeat on next board.
For this precision you need a proper frequency/period counter. -
I guess my questions maybe doesnt contain all relevant information since I'm really new to all of this but a resolution of 3 decimal points should be good enough.
At 500Hz a DS1054Z will show 3 decimals on screen using its hardware frequency counter. It's usually quite accurate but I don't have anything else here that can measure to 3 decimals to compare the two side by side. I'd probably trust it to two decimals.
If you have a known-good reference frequency and a 2-channel 'scope then you can connect both signals to the 'scope and turn the trimmers until the signals don't drift relative to each other. This will be at least as accurate as looking at the frequencies to three decimals, maybe more.I need to be able to octave trackck the VCO.
For example
C0 Note
1v Octave V: 0.0833
Expo Output: 0.1655
Frequency: 65.4078
A2 Note
1v Octave V: 2.8333
Expo Output: 1.1136
Frequency: 440.0092
...and now we're at 4 digits.For this precision you need a proper frequency/period counter.
Yes, a dedicated device is always better.
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At 500Hz a DS1054Z will show 3 decimals on screen using its hardware frequency counter. It's usually quite accurate but I don't have anything else here that can measure to 3 decimals to compare the two side by side. I'd probably trust it to two decimals.
If you have a known-good reference frequency and a 2-channel 'scope then you can connect both signals to the 'scope and turn the trimmers until the signals don't drift relative to each other. This will be at least as accurate as looking at the frequencies to three decimals, maybe more.I need to be able to octave trackck the VCO.
For example
C0 Note
1v Octave V: 0.0833
Expo Output: 0.1655
Frequency: 65.4078
A2 Note
1v Octave V: 2.8333
Expo Output: 1.1136
Frequency: 440.0092
...and now we're at 4 digits.
The specification states, for the delta time measuring accuracy: Single-shot: ± (1 sample interval + 50ppm × reading + 0.6 ns)
In this case the most relevant term is the (50ppm x reading), which leaves the 4 digits counting from the 1st. one. The measurement would be accurate to the 1st. decimal digit. I think aabbcc is asking for 7 full digits precision, something he will not get in a direct way from an oscilloscope. Of course, as you said previously, there are indirect ways to use an oscilloscope to provide that precision, but to do that one needs a signal source precise enough too
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If he needs to adjust trimmers then I strongly doubt he will get 2 digits of precission long term and/or with temperature variations.
In this case the most relevant term is the (50ppm x reading), which leaves the 4 digits counting from the 1st. one. The measurement would be accurate to the 1st. decimal digit. I think aabbcc is asking for 7 full digits precision, something he will not get in a direct way from an oscilloscope. -
If he needs to adjust trimmers then I strongly doubt he will get 2 digits of precission long term and/or with temperature variations.
In this case the most relevant term is the (50ppm x reading), which leaves the 4 digits counting from the 1st. one. The measurement would be accurate to the 1st. decimal digit. I think aabbcc is asking for 7 full digits precision, something he will not get in a direct way from an oscilloscope.
Calm down, "trimming" can be digital, too.
I didn't know how his devices work, "trimmer" seems an appropriate word.
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If he needs to adjust trimmers then I strongly doubt he will get 2 digits of precission long term and/or with temperature variations.
In this case the most relevant term is the (50ppm x reading), which leaves the 4 digits counting from the 1st. one. The measurement would be accurate to the 1st. decimal digit. I think aabbcc is asking for 7 full digits precision, something he will not get in a direct way from an oscilloscope.
Calm down, "trimming" can be digital, too.
I didn't know how his devices work, "trimmer" seems an appropriate word.
It seems that his application is music so "tuning" could be a better word.
Anyway, I think we are straying from the original topic (at least, the requirements are totally different) and this one could be worth a thread of its own... -
It seems that his application is music so "tuning" could be a better word.
Analog synths are well known for being tempremental and a bit out of tune. All those VCOs, etc.
(Although to be fair a lot of the error comes from tolerances of the resistors in the analog keyboards)
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One of life's lessons sadly even from reputable, or what you think are reputable companies. Perhaps are not, and may be lying to you. Do you have confidence in your equipments CAT ratings?
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One of life's lessons sadly even from reputable, or what you think are reputable companies. Perhaps are not, and may be lying to you. Do you have confidence in your equipments CAT ratings?
Great question...... In the computer industry which is what teach students do you have confidence in anything? Heck there are fake Cisco routers and router boards and even Apple has to contend with fake Apple Stores. -
I think it's interesting that a number of you are bullying me and telling me I'm incompetent for not protecting students for accidently getting zapped in my class. Now we are getting into gloves, eye and ear protection.
It's ocuring to me we might have different defiantuons for the word mains? So before you zap me with a cattle prod what's your defination for mains? Mine is household voltage. I'm in the US so that would be 120 vac. When studnets measure the votage at the "mains" at a power supply of say a router to see if the fuse is good. We are takling 120 vac. For this test are you telling me they should be weaing gloves and have eye and ear protection?
Is this something you even do?
How many of you working in the electronics filed have never received a zap? Come on, be honest.
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You want honest? LOL, buckle up mate
Lots of zaps here, a great survivors collection actually,
and a firm reinforced belief in God and or Crew above (Thanks again!)
Let's see:
nice wacks, cracks, sparks, and shrapnel at 6, 12, 24, 48, 60v DC, from automobile, UPS, server and laptop PSUs
2 awesome near death experiences on 240 volts AC, one as an unnattended child playing with a junked 1960s open backed stereo 'all in one',
and one much later when I got into repair work
If I was taught and cautioned properly back in the day, especially about earth ground bonding at the mains,
none of the above would have happened, as they haven't since for years once I unlearned a lot of mashed electrical fundamentals and electronics voodoo BS,
and relearned properly how stuff works, and what scenarios are possible when stuff isn't working as it's 'assumed' to be.
FWIW back then (as today!) had I been wearing $4.99 tradie eyewear, $2 shop cowhide gloves and jammed some tissue in my ears, I would have needed less luck to get through the above unscathed
Most stupdents in the classroom are more concentrated on their Farcebook status and hipster nonsense than any cautions the teach is trying to pump into them, let's get real here...
Protect the little twats as best you can from themselves,
otherwise their cashed up parents will zap the school and you real good,
into legal labyrinths, financial oblivion,
and a future applying for non-teaching dead end jobs!
Please consider before applying the bullying stamp here
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I think it's interesting that a number of you are bullying me and telling me I'm incompetent for not protecting students for accidently getting zapped in my class. Now we are getting into gloves, eye and ear protection.
It's ocuring to me we might have different defiantuons for the word mains? So before you zap me with a cattle prod what's your defination for mains? Mine is household voltage. I'm in the US so that would be 120 vac. When studnets measure the votage at the "mains" at a power supply of say a router to see if the fuse is good. We are takling 120 vac. For this test are you telling me they should be weaing gloves and have eye and ear protection?
Is this something you even do?
How many of you working in the electronics filed have never received a zap? Come on, be honest.
As an employer (if I were one), I would be obliged to see that my employees had suitable personal protective equipment whenever they worked on anything over 50V. At a minimum, eye protection and low voltage rated gloves. Seriously! I would have to provide gloves for work on energized 120V circuits.
This is the rubber glove but it can't be used without the protectors:
https://www.magidglove.com/Salisbury-by-Honeywell-E0011-11--Class-00-Rubber-Linemens-Electical-Gloves-E0011BL10.aspx
https://www.magidglove.com/Magid-PowerMaster-Linesman-Low-Voltage-Protector-Gloves-126049-1-12604115.aspx
Moreover, I would have to have a rather complex sign-off procedure before energized work could be done at all. There would need to be a sign-off on WHY the work had to be done while energized. I would also have to have a documented Lock Out - Tag Out (LOTO) training program. We can't just turn off the breaker, we need to prevent someone from turning it back on and we need to tell the world why it was turned off. (if we couldn't effectively lock the breaker, it had to be unwired.
For those of us who were considered 'jailable company employees', we took this stuff seriously. No screwing around; written procedures, documented training, spot inspections, the whole program.
Everybody gets to make their own choices but some are really bad...
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I think it's interesting that a number of you are bullying me and telling me I'm incompetent for not protecting students for accidently getting zapped in my class.
Really, poor you.
There is no way students at school at this level should be exposed to anything that 'zaps' them and at this age the teaching of formal safety procedures is not given, it's reserved for after they start employment and at a time when they could be viewed as more responsible.
My early electronics 'education' started at seven when pop bought me a Philips 2 transistor electronics set that was powered with a 9V battery. Before teenage years I was fiddling with petrol motors whose ignition systems gave a healthy wack which is where 'respect' for electricity was gained. In my first year at high school I'd already been working on valve radios and got several shocks, the worst of which was 700V from a HV plate PSU. 230VAC mains 'tingles' followed in later years when I thought I had sufficient 'ability' and experience to start working with it.
From that school of hard knocks (AND NO FORMAL TUITION) I've not had a shock in ~30 years due to the healthy respect gained....in my own time !
Teach them about the dangers but DON"T expose them to any ! ! ! ! !
I've seen educators like you before......I'm always right.
Yeah right !