Oscilloscope? $110 budget

[tuk]

already have a decent volt meter but I'm thinking of buying a cheap Oscilloscope as part of learning about design/build small circuits, micro-controllers(arduino), RC filters, small amplifiers, relay drivers...that kind of thing. ..I can't see into the future or know enough atm to choose..so that's where you guys come in...

my absolute max budget is $125 ..another option would be to buy something used..it might be 30 yrs old, but will have 2 channels and some nice spec ..been looking at hamegs, tektronics, gould, lg etc ..eg Tektronix 2215 60 Mhz Dual Ch Dual Timebase Oscilloscope...but I doubt I could make repairs if it goes down or is delivered faulty and also wonder if they are toxic somehow?

....so new but crap or old but good? ...here are some examples I found within my budget

Poor Man's Oscilloscope
not sure how much use this will be and would really prefer something separate from the pc but I'l include as it's the cheapest and has 2 channels....and some might think there's no point paying more

$10-$15

my soundcard spec:
Creative Sound Blaster X-Fi Xtreme Gamer
Interface Type: PCI
Signal Processor: Creative X-Fi Xtreme Fidelity
Sound Output Mode: 7.1 channel surround
DAC Data Width: 24-bit
Sample Rate: 8 kHz (min) - 192 kHz (max)
Signal-To-Noise Ratio: 109 dB

DSO Nano v2
spec could be better and uses battery ....but nice screen

$100

Full Color 2.8" TFT LCD 65K 320×240
80Vpp (by ×1 probe)
0 - 1MHz
10Hz~1MHz square wave
1Msps 12Bits
4096 Point
1uS/Div~10S/Div
10mV/Div~10V/Div (with ×1
0.5V/Div~100V/Div (with ×10
500K
Auto, Normal, Single, None, Scan and Fit
Rising/Falling edge/level trigger
Trig level adjustable with indicator
Trig sensitivity adjustable with indicator
Auto measurement: frequency, cycle time, duty cycle,
peak voltage, RMS voltage, Average voltage and DC voltage
Precise vertical measurement with markers
Precise horizontal measurement with markers
Hold/Run
Micro SD card
as SD card reader
USB
500mAh 3.7V Lithium battery / USB

DSO 082
good spec/features for the money but the screen looks small...some video in the link

$110

Vertical
Number of Channel: One
Analog Bandwidth: 0 - 10MHz
Sensitivity: 10mV/Div -- 5V/Div
Resolution: 8-bit
Input Impedance: 1M ohm
Maximum Input voltage: 50Vpp (for 1X probe)
Coupling: DC, AC, GND
Horizontal
Max Real-time Sampling Rate: 50MSps
Timebase: 0.2us/Div - 10s/Div
Record Length: 2000 - 16000 points user selectable
Zoom-in: Up to 10X in HOLD mode
Run/Hold Modes: one button switchable
Trigger
Trigger Modes: Auto, Normal, Single
Trigger Types: Rising/falling edge
Trigger Sources: Internal/external
Trigger Position: Adjustable
Trig Point Indicator: Yes
Other Features
Save/Recall up to 4 captures
Screen image hardcopy
USB connection for data transfer and firmware upgrade
FFT with selectable length of 256, 512, or 1024 points and sampling rate from 1KSps to 50MSps
Rotary encoder for quick parameter setting
Display
2-inch 128 X 64 black-and-white dot-matrix LCD
Backlight ON/OFF control
Contrast adjustable
Power Supply
9V AC/DC power adapter
Supply voltage range: 8 - 12V
Supply Current: 300mA (LCD backlight ON, typical)
Reverse polarity and over-voltage protected

HPS140 Handheld Pocket Oscilloscope
seems easy to use but overpriced for what you get ..uses battery

$125

bandwidth: up to 10 MHz (-3dB or -4dB at selected ranges)
input range: 1mV to 20V/division in 14 steps
input coupling: DC, AC and GND
real-time sample rate up to 40MS/s
AD resolution: 8 bits
time base: 250ns to 1h per division
auto set-up function (or manual)
probe x10 readout option
readouts: DC, AC+DC,True RMS, dBm, Vpp, Min-Max. (±2.5%)
audio power measurement from 2 to 32 ohms
hold & store function
time and Voltage markers readout
Max. 100Vp AC+DC
white LED backlight
operates on NiMH rechargeable battery pack (included)
operates up to 6 hours on one charge*
charging power supply: 9Vdc/200mA
for use on CLASS II pollution degree II installations

 

[davenn]

those last 2 are particularly respectable low price units. and you would get a lot of use out of them before u finally needed to upgrade to something that had a wider bandwidth. 10MHz is all you need for audio and low speed digital stuff.
Just remember tho..... a decent probe will cost you almost as much
top quality probes can go for $500. very respectable ones for ~ $100

look around for a good quality used one maybe. maybe you already have something useable

cheers
Dave

 

[daddles]

Those small oscilloscopes may fit your needs just fine. Personally, I would never want one because I like modern scope sizes and, most importantly, I want the buttons and knobs on the front panel.

One of the most difficult thing for a person thinking about buying a scope is to have the ability to try out different scopes. This isn't too hard for an engineer working in industry, but for a hobbyist learning things on his own, it can be a real challenge. Thus, if you're going to do it, you need to figure out some creative ways to get your hands on a variety of scopes for a while. There's really no substitute for hands-on experience.

Some thoughts: advertise locally for like-minded hobbyists. Tell them that you want to get some time on their scopes; offer something that will interest them in trade (you may not need to trade anything, but you catch more fish with bait than an empty hook). Check out local ham get-togethers; they apparently are good places to find things (I've never been to one, so my data are second-hand). Go to a local college and ask the engineering or physics departments if you could do some volunteer work for them in exchange for some time on their scopes. Similarly, contact some local businesses that would be likely to have scopes and try to figure out some creative way for mutual back scratching. Also contact a local business and tell them that you're looking for an older used scope and do they have one they might be interested in selling so they could upgrade.

davenn is quite correct about the probes -- don't neglect them. You also may want a differential amplifier for your scope and they can go for $300-$1000 US or more. Oh, then you'll want a current probe -- and that can be even more money... Oh, wait, now you'll need a function generator for stimulus. Oops, now you need some fancy RF coax cables and adapters (looked at any Pomona stuff lately?)... It never ends...

 

[(*steve*)]

The soundcard option is rubbish. You can demonstrate some concepts and you can do some *very* basic measurements, but erk.

The DSO Nano is interesting, but I wouldn't recommend it as a first scope. I have one and its portability is great, but you have to compare signals on this and a real scope to see what you're missing. In any case a cheap second hand scope will have wider bandwidth, better controls, and a larger screen.

The same arguments go against the others too. Perhaps they have better bandwidth.

I've recently compared my steam powered analog 60MHz dual trace scope against a 100MHz digital scope (a Rigol). I was less than impressed with the Rigol. And that's a real shame because I was prepared to buy one before I saw one in action. Honestly, I would compare it to mt DSO Nano rather than my steam powered Philips CRO.

My advice... Try to get an analog scope.

edit: Oh yeah, the probes. I paid more for my probes than for the scope. Then again, they are very nice HP probes. You can get cheap probes from China and one day I might get some just to compare them to mine.

 

[tuk]

thanks for the replies all; very helpful, I think I will monitor ebay for a week or 2 to see what I can pickup for less than $125 ...do you guys have any recommendations for particular brands of old scopes ..I have been looking at the HAMEG HM203, Gould OS300 and Tektronix 2215

if nothing catches my eye on the bay, I might leave buying an analogue until further down the line when I know more about what I'm doing, have played with a few other scopes and have more money to spend....and in the meantime buy a cheap digital to get me started...

...on that note I would probably go with the DSO 082, as I think the spec slightly edges it over the others(unless I hear different), and has some other interesting features according to the manual ..plus it comes with a 20 mhz 1x,10x BNC probe photo ..I know it will be a cheapo but still

DSO 082 - $110
Analog Bandwidth: 0 - 10 MHz but its actual -3db bandwidth is closer to 15MHz .
Max Real-time Sampling Rate: 50MSps
Maximum Input voltage: 50Vpp (for 1X probe)
Sensitivity: 10mV/Div -- 5V/Div
Timebase: 0.2us/Div - 10s/Div
FFT with selectable length of 256, 512, or 1024 points and sampling rate from 1KSps to 50MSps

 

[tuk]

bit of an update & hopefully get some quick advice on probes ...plz

I'm now the proud owner of a Tektronix 2215A for $112 ...see pic below

60 MHz Bandwidth
2 mV Sensitivity
5 ns/div Sweep Rate
Advanced Trigger System
Delayed Sweep Measurements

FULL SPEC & MANUAL

had to dip into next months rent to cover shipping..but I think/hope it's worthwhile in the long run, I need 2 probes fit to test the scope is working when it arrives and also some tinkering with simple MC projects(see OP)...but have no idea what kind of probes I require?

do both probes need to have the same values?...I'm already broke so has to be cheap and cheerful until such times I can buy something better ..BUT making sure the scope is functioning properly when it arrives is my main concern

what about something like this?

"Oscilloscope Scope Clip Probe 100MHz For Tektronix HP"

 

[tuk]

....or

 

[daddles]

had to dip into next months rent to cover shipping..but I think/hope it's worthwhile in the long run, I need 2 probes fit to test the scope is working when it arrives and also some tinkering with simple MC projects(see OP)...but have no idea what kind of probes I require?

do both probes need to have the same values?...I'm already broke so has to be cheap and cheerful until such times I can buy something better ..BUT making sure the scope is functioning properly when it arrives is my main concern

If you live in the CONUS, I have some older HP probes. I'd be willing to sell you a couple of them cheap, as they're missing the thingy that slides over the barrel so that you can clip them on to things (some are missing the ground clip too). I'd check them out on my HP scope to make sure they're working OK first. If you're interested, PM me and tell me the bandwidth of your scope. The model numbers I have are: 10081A, 10017A, 10041A, 10018A, and 10006D (they're all 10X probes).

 

[(*steve*)]

The ones I use are HP10042A which look very similar to these and cost more than my scope

 

[poor mystic]

I think that this thread could be marked as special for the benefit of posterity.

 

[tuk]

cant pm you for some reason daddles..it says you may have pm disabled..I live in the UK

I made a table of some affordable contenders, I have been reading up on scopes/probes with my limited knowledge ..keep me right here....if my scopes capacitance is 20pF then I should be looking for a probe with a compensation range which includes 20 right? ..so out of the probes in the table...10-50pF*is best as it covers 20 and has the widest compensation range ...also lowest input capacitance/resistance and rise time... this probe is better in all areas when compared to the others?