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Am looking into purchasing a 1st Oscilloscope and am curious what MHz others
use for pic related projects?
It seems most interfaces to micro's require timing.
Would an ebay 100 or 200 MHz be good or would an older (<$) 400 MHz be
advantages?
I have seen the sites with technical descriptions of MHz required but would
like to know what others are using?
Norm
My Lab contains equipment good to about 1.5GHz. Despite that, I prefer to use a good quality dual trace 20MHz scope. The number of times I've needed to go beyond that in the last four years I can count on the fingers of one hand - and then it was only because the faster scopes had the ability to display on-screen wave analysis statistics rather than the need to actually display a fast waveform.
Ultimately, it's all down to what kind of applications you're playing with. I know I'd rather have a scope that is in-calibration and I can rely on to tell me a resemblance of truth, than one whose results can't be trusted. There's more to chosing a scope than raw MHz on the timebase.
Hi, Normnet
Great truth from Mel's post ... my favourite osc is just an old 2 x 20 Mhz ( Hameg 203 - 4 !!!). as a first scope, it's perfect.
For 20 years ... ( yess, right ! ) the only things I did not do with it, is to catch vicious glitches ( sometimes helpful , then ...) and look at HF signals > 35 Mhz - OK to verify if a Pic Clock is running...
The next model will be a 2x50 Mhz ( no more ! ) , but W/ memory as I noticed the most difficult signals to observe are ... very slow or non cyclic !!!
cursors are also convenient for measurements ...
Hameg 507 ... may be. for no more than ~ 1200 $ ( brand new ...)
Alain
Hi!
- How much are you willing to spend?
- Second-hand or new?
- Have you ever used an oscilloscope?
- Going to be used for hobby, profession or future profession?
- Used mostly for microcontroller-based designs?
At home I have two oscilloscopes:
Tektronix 465 Oscilloscope, 1974 model.
http://www.amplifier.cd/Test_Equipme..._other/465.htm
I got it for free in the year 1991. The oscilloscope was in a Bank
as part of the on-site maintenance equipment tools for 5 large hard disks.
The oscilloscope was dismantled together with hard disks in 1991.
After 30 years the oscilloscope is still working and is still like
new. (Used only after 1991).
=================================================
Agilent 54622D Mixed-Signal Oscilloscope. (Formerly Hewlett-Packard).
http://www.testequipmentdepot.com/hp...s/hp54622d.htm
I bought it new in the year 2001. (My wife did not approve).
Great equipment, I use it all the time.
The Agilent 54622D 2+16 channel, 100 MHz Mixed-Signal Oscilloscope (MSO), with two scope channels and 16 logic timing channels, uniquely combines the detailed signal analysis of a scope with the multi-channel timing measurements of a logic analyzer. It lets you trigger on and view the complex interactions among your signals on up to 18 channels simultaneously. The 54622D is ideally suited for CPLD and MCU based applications.
Features:
- Unique 2+16 channel MSO model
- 100 MHz
- Patented high-definition display with superior horizontal resolution
- 4 MB of MegaZoom deep memory mapped to 32 levels of intensity, 25 million vectors/sec.
- Powerful, flexible triggering including I²C, SPI, LIN, CAN and USB
- Standard built-in floppy, RS-232 and parallel ports, FFT's
- Quick Help in 11 languages
Best regards,
Luciano
I think there is not much to add.
A good dual channel 20MHz scope would be good to start with.
I got my first one (including two good probes)
second hand at $100,
(a great bargain)
and it is still doing a good job.
Check ebay,
there are many HAMEGs (and others)
in the $150-$250 range
As Luciano has already mentioned,
is is a matter of what you can afford to spend.
My second scope is a Fluke 123 which I really like.
But to be honest, more than 90% of the time I use the "old" 20MHz analog scope
as it has a fixed place on my bench.
i agree with the old analog too. It also gives you one more advantage. If you need to, you can use those one with a simple circuit to have a 8-16 or more channel scope. This can be handy in some case. You can't do it with a digital one.
I started out with an old Government Surpluse scope.. Good to 20 mhz. That was extremely good...
Then I purchased a IFR Spectrim Analyzer Good to 1 gig, and that smoked cigarettes, drank beer, and cleaned your house for you at the same time...Then I purchased a FLUKE 123... And between the cheapie and the 123 scope, I use them equally. I sold the IFR Analyzer (It was just way too much for what I did, and I got to put 3000 dollars in my pocket at the same time <chuckle>.) The fluke has many MANY options that are just REALLY nice. IT goes BEYOND a scope. If I were to compare my 12000 dollar Analyzer to my Fluke 123... The fluke did almost everything the IFR Analyzer did when it came to scopes and accessories. Granted it didn't have the receiver, Spectrim Analyzer, Freq Range, Various inputs, Deviation, AM/FM and other stuff... But I never used them. They just "Were there". The Fluke can see some things easier if the "spikes" are extremely quick. And in "AUTO" mode, its kinda nice to have the meter do all the stuff for you <chuckle>. But if you get right down to it... my old Scope does just as good of job, with solid preformance. I think you can pick up one for about 100 dollars or so.
I have a OLD very OLD EICO scope...i am trying to figure out what to do with it... It works... I can't remember the speed, but it was made in the 1960's... Great working boat anchor. I think todays chips are too fast for it <g>... Its kinda neat to see that "O" in the middle of the screen.
Dwayne
Dwayne you raise an interesting point about the display speed and/or acquisition time.
IMHO, a cheap analogue will display better and faster some little glitches or noise on a line than many digital model due to the sampling rate and so many other reasons. This is why i like yes and no the digital ones for some applications. The same for digital multimeter and old VOM. but this is out of the current thread.
I have several scopes from a 10mhz Picoscope to a 100mhz dual channel Tektronix. What I found was the analogue scope was ok if you have repeating signals. But as all I seem to do is work with Pic's It's not much use as I'm trying to capture 1 shots or analyse data trains so my Pico scope still gets a good look in. If I had the money and needed a new scope I would plumb for a high speed PC scope and be able to capture the signals when needed.
That's a point. If you have some Visual Basic ability, you can also built your own datalogger or call it as you want. Easy to do in conjuction with the free
Softwire software as Bruce already suggest on this thread. Grabbing the serial PORT or Parrallel port becomes easy with or use the INPOUT32.DLL within VB. quick tutorial here
Hello Steve,
For a good example that I ran into about 1 week ago....
I was using a 675 and a 648A with serial communication between them. The 648A is attached to a LCD for a homemade "Backpack".
I was using 675 for Pulsin, and decided to increase my frequency using another 648A pin and making a Psuedo PWM signal The Pulse was a instant on, Instant off, so the timing was very short. On my Old scope I was showing nothing. I had to go to my FLUKE, and my FLUKE showed a "Spike". Though that spike was just a thin line, I *knew* something was there. I took my old scope, and set it to the EXACT settings of my fluke. I still could not see the "Blurp". I adjusted the light density (which was EXTREMELY bright) and STILL could not see the Blip. After playing a little bit, I was barely able to see the blip on the scope. And I had to slow down the scope to see them... This has been the first and only time I have run into this problem. I switched to a 60 mhz scope, and had the same exact problem seeing this Blip. If it wasn't for my fluke, I am quiet sure, I would have missed it all together.
Though I really like the FLUKE VOM's too, I actually prefer the old meter VOM over the LCD's for many things. The meter tells me a lot by its movement...I can't tell if the LCD kind is switching modes because of bad contacts, or varying voltage <g>. But either way...If I were to buy, It definitely would be a Fluke... They are shock Proof, water proof, and Definitely worth the extra money. Yeah.. they are small, but they sure are wonderful to use. I think they run 600 dollars (for the 123) on Ebay. But they are workhorses. The only thing I do not like about the 123, is that the battery pack doesn't last a long time. Maybe 30 min to 45 min or so. The 123 does have a automatic battery cycler, but anyone who REALLY nows about Nicads, KNOWS you never discharge NICAD batteries to zelch. Big mistake, yet Most folks are clueless on this.
Dwayne
Steve
When I want to do any serious datalogging I use my old 16 channel dos based PC data logger. I got it free with my £100 Pico scope what must be 6 years ago, the logger design as been around for about 10 years, sadly not available now. Still runs although not on my XP machines, unless I use Dosbox.
I have attached a BMP picture of an electrical
signal taken with my digital oscilloscope.
Best regards,
Luciano
One must have received the Nobel prize before understanding such an operator manual ...
And also won the Tottocalcio ...
mmmh ... I suddenly remember our friend was looking for a FIRST scope ...
Alain
Bonjour Alain!
The Agilent 54622D is surprisingly simple to operate.
You are right, my hobby budget was in red for a long time.
(Some people spend the same amount of money for a mountain bike).
With the BMP picture I just wanted to give an idea of what can be
done with a modern digital storage oscilloscope.Amazing is also the
trigger section of this DSO.
An analog scope is perfectly fine but a DSO is a different world.
Best regards,
Luciano
my 2 cents... i also have Tektronik TDS200 with the communication module. It can also be a great choice and cheaper. The newest version of TDS200 are great too.
Hi, Luciano
Can be THE thing ... from ( ...) 5500 $ !!!
Alain
Purchased: B+K Precision Model 2522B combination “digital storage / full analog” oscilloscope.
http://www.bkprecision.com/www/np_specs.asp?m=2522B
Norm