Help-Oscilloscope!!! - Page 1
Forum section: electronics / beginners

author: nelus008
author_rank: Newbie
timestamp: April 09, 2013, 04:01:29 am
content: Hello people! I'm new here and new in this field so I came here to get some help...I need an advice about the oscilloscope Trio Kenwood CS-2070. It will be my first oscilloscope and I really need to know if it's a good one, should I buy it or I better try something else? What do you think about this brand and this model???Another question is about how to check if the oscilloscope works properly because I will buy a second-hand one and I need to know how to verify if everything is ok. I have to say that I'm a newbie, I never had an oscilloscope and I don't know how to test it.Please help!Regards,Nelu

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: April 09, 2013, 05:28:59 am
content: I dont know this scope so I can't tell you much about it, but it's probably worth mentioning how much the scope costs and where you live, so people could give you some price comparisons.

author: amspire
author_rank: Super Contributor
timestamp: April 09, 2013, 06:21:24 am
content: If it is really cheap - like $20, then go for it. Any scope is better then no scope.However it is a very basic scope, and nowadays 10MHz bandwidth is a real limitation. For example, if you want to play around with an arduino, it runs at a clock speed of 16MHz. This scope is not fast enough to accurately see the pulse edges from the Arduino. A 5V peak-to-peak squarewave clock will appear on this scope as a 2V peak to-peak sinewave.If you are planning on doing audio and opamp work, it is probably OK to start with.If your budget is around $50-$100, try for an analog scope with 50MHz or more bandwidth and a delayed sweep.If you can afford something like a Rigol DS1052E or a DS1102E, you will probably not regret it. They are pretty magical compared to the basic analog scopes. As Dave recently pointed out, the Rigol 2000 series at double the price again is worth the extra money, but we are now talking about a really big jump in price. A DS1052E can cost as low as $300 - $330 and it is still an extremely powerful digital oscilloscope.If you want to work with microcontrollers, like the Arduino, a digital scope is great as you often need to capture one-time events. The analog scope can only capture continually repeating events.Richard.

author: nelus008
author_rank: Newbie
timestamp: April 09, 2013, 07:11:18 am
content: The scope is 70 mhz, 4 channels, so from what you're saying i guess it's ok..But how can i test it when i buy it to see if everything works ok? Because as I mentioned it will be a second hand one and I don't wanna get a scam that doesn't work as it should, so how can I check this? What do I have to do?

author: psycho0815
author_rank: Regular Contributor
timestamp: April 09, 2013, 12:53:32 pm
content: check daves video on the tektronix 2225 scope. He talks a bit about what to look out for. Of course if you don't have a function gen it's gonna be tough to actually test anything.

author: amspire
author_rank: Super Contributor
timestamp: April 09, 2013, 02:07:38 pm
content: Quote from: nelus008 on April 09, 2013, 07:11:18 amThat sounds much better. My quick search came up with 10MHz, but that was obviously wrong.The manual is available here:http://elektrotanya.com/trio_kenwood_cs-2070_70mhz_oscilloscope.pdf/download.htmlIt is a delayed sweep scope, and Trio-Kenwoods are not bad. If it is at a good price, it is fine for a first scope. The manual is fabulous - schematics, parts lists, PCb layouts, waveforms. Probably no custom semiconductors. Not a Textronix scope, but pretty good.

author: nelus008
author_rank: Newbie
timestamp: April 09, 2013, 02:58:59 pm
content: It cost me 180 $.I read the manual and I saw that I need some equipments to verify it: sine-wave generator sg-502 from tektronix, a q meter, an attenuator ...etc. but I don't know how to use them!Is there any way I can test the waves without all those equipments? It is enough to connect the probe from CH1 to CAL and then make some adjustments to position, AC-DC, and VOLTS/DIV to see what wave I get??

author: amspire
author_rank: Super Contributor
timestamp: April 09, 2013, 03:20:51 pm
content: If it is working fine, don't even think about adjusting anything except the frequency compensation on the probes.If the cal out displays as a square wave on both channels, that is a good start.It is probably in-calibration, and the first task is to learn how to use it.

author: nelus008
author_rank: Newbie
timestamp: April 13, 2013, 09:12:33 pm
content: I have the perfect square wave on both channels, but I can't move the XY spot outside the screen in the left side. It works for right side, top and bottom, but not for left side, why that?Another thing: when I try to measure something like an transformer, the wave is flickering..why that? Is because I don't know how to set it or is because something is wrong?

author: Paul Moir
author_rank: Frequent Contributor
timestamp: April 14, 2013, 02:50:17 am
content: I don't know that scope, but the X-Y thing may be perfectly normal. The usual way to use that function is to centre the spot on the screen, and feed a signal in through the X and Y channels to move the spot around.As for the flickering; that's typical if your triggering is a little marginal. Try "playing around" with the triggering functions to get it figured out. Or post a picture of your scope so we can see how you have the trigger set. That's assuming that "measure a transformer" is what I'm assuming it to be: you probing between the secondary (low voltage side) on a power transformer plugged into the wall, with the probe tip connected to one wire and the probe ground to the other.(PS - be careful with the spot as it's very easy to burn the screen on an oscilloscope if the intensity is set too high. Something you might not know about since you're a beginner).