I am just starting electronics and I think a scope would be a good way to see what is going on. The cpc.farnell (UK) web site has 6 listed between £90 and £180. Are these worth it, or are they junk, is there a better suppler (UK), do they need to be calibrated (£?), is 10MHz good enough, what other specifications should I look for?
I know this is a subjective question, with a 'depends what you want it for' kind of answer; I have been working through Brindleys starting electronics and I want to do stuff with 555's and 741's on a bread board, and then quite small projects.
The least amount possible. That is the least amount that will get me something that is worth having for simple hobby work. I guess this is how long is a piece of string territory, so no one is going to be able to give an answer, ah well never mind, I'll maybe take a gamble...
This topic has been discussed in many threads in the past, so it would be useful for you to search a bit and see what you can find. There are several opinions on this matter, because as you say, it depends on what you are doing. In general though, the beginner should work with a 100MHz bandwidth because the typical microprocessor circuits often have fast rise and fall times and to see these accurately, 100MHz bandwidth is the minimum requirement. From my experience, a high quality analog scope (Tektronix or Hewlett Packard for example) is the best value for the beginner. They sell for less than $200 and sometimes for less than $50. A good digital scope with equivalent performance often starts at $250 and goes up from there.
The simple analog scopes that I have much success with in the past include HP1725a, Tek 465, HP1740. My favorite series of entry level digital scope is the Tektronix TDS20xx series, but these are very new and too expensive most of the time. Many others have enjoyed using Tektronix 24xx and 22xx series and TDS3xx or TDS4xx series which are older digital scopes. I do not happen to like these very much as the front panel controls have poor feel and poor layout in some models. However, other than that, many older Tektronix and HP or Agilent scopes can be very good value if you can get one at a good price that works well.
If it's just for audio or the odd PIC circuit 10MHz is enough. A 10MHz 'scope will be able to tell if an audio amplifier is oscillating and you should be able to see a 4MHz clock signal with it although (as Ron says) you won't be able to gauge the rise/fall time.
If you need to get into digital electronics then you'll need a faster 'scope, 100MHz should be good enough to most applications.
I am not total sure. I don't need storage. I am not too fussy on accuracy, but it need to be good enough to be meaningful. I want to do digital, but I don't really knoe what that means yet I am thinking of the TECSTAR - CS1010 - 10MHZ OSCILLOSCOPE
Thanks, Rob.
PS
In the UK the cheapest 100MHz scope I can find is £616. But then my search skills are a bit duff as I did not find anything here on 'which budget scope to purchase'
I am not total sure. I don't need storage. I am not too fussy on accuracy, but it need to be good enough to be meaningful. I want to do digital, but I don't really knoe what that means yet I am thinking of the TECSTAR - CS1010 - 10MHZ OSCILLOSCOPE
Thanks, Rob.
PS
In the UK the cheapest 100MHz scope I can find is £616. But then my search skills are a bit duff as I did not find anything here on 'which budget scope to purchase'
149 UK pounds doesn't seem like a very good value. Those of us in North America have better access to a much larger market of used high quality scopes, so when I looked at Ebay UK I was disappointed with the selection and prices. In any case, this one would be a better value at about 50pound or less:
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It appears that used 100MHz digital scopes tend to sell in the range of 80 to 150 UKpounds on ebay UK. This one seems typical:
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Thanks, I see that I need two channels, and probably 100MHz => not new. The Tecstar is on offer at £100.62, but it is 1 channel & 10MHz, so I'll have to go for the 2nd hand market. I am not too desperate, so I will bide my time. Thanks for definitive information.
It broke once but has started working again although it isn't perfect, the display does oscillate (flashes on and off) at low brightness settings. It's still perfectly usable as long as you don't turn the intensity down too low.
It you can come round and collect it then you can have it for £10.