I would recomend at least a 20mhz or better I have been using a 40mhz Hitachi V-425 for 25 years and have rarley wished I had anything better!
But IMHO go with a good analog one!
I think it would be easier to use and you will get a much better picture of realtime waveforms.
Especialy when running into parasitic oscillation problems and doesn't require a pc.
They can be had fairley cheap these days as I paid over $900 for mine back in the mid 80's.
Keep in mind that on screen measurement is a godsend when you are shopping around.
I am sure that some others may beg to differ but it is my best opinion.
jer 🙂
But IMHO go with a good analog one!
I think it would be easier to use and you will get a much better picture of realtime waveforms.
Especialy when running into parasitic oscillation problems and doesn't require a pc.
They can be had fairley cheap these days as I paid over $900 for mine back in the mid 80's.
Keep in mind that on screen measurement is a godsend when you are shopping around.
I am sure that some others may beg to differ but it is my best opinion.
jer 🙂
Uh, for that price I'd look at ebay for a good used tek or HP. In the new category I couldn't think of a single acceptable one in that price range. Look at Tek 2200/2400 series or an HP1700 series.
Doc
Doc
I have to recommend my old trusted Sencore SC-61 this is a hidden gem with LOTS of useful features! you can buy them often for about $100, they are a 60mhz scope usable to 100mhz. and they are very reliable! If you can find one with the original Secore probe, go for it. while you can use any standard probe, the original sencore probes are worth a fortune!
I have had MANY used Teks and HP scopes, even a few Hitachi's. and frankly the older Tek and HP scopes always ended up giving my trouble right when i needed them most! My sencore has run for 15 years now with the only issue being one dirty switch! I do miss my old Tek 5103N scope with the massive 6" screen, but it had such limited bandwidth!
Not many people know about the sencore scopes. I just love them! and for someone buying their first scope! these are great!
Zc
I have had MANY used Teks and HP scopes, even a few Hitachi's. and frankly the older Tek and HP scopes always ended up giving my trouble right when i needed them most! My sencore has run for 15 years now with the only issue being one dirty switch! I do miss my old Tek 5103N scope with the massive 6" screen, but it had such limited bandwidth!
Not many people know about the sencore scopes. I just love them! and for someone buying their first scope! these are great!
Zc
In the $100 to $200 range you will be limited to older/off brand analog scopes, and toy digital scopes.
At one time one of the early Tek 400 series scopes would my first recommendation, the 100MHz 465 being one of the best being great deals in that price range, however they are now all 30+ years old and not really viable unless you want to wade through the problems with front end attenuators, scratchy pots, and the failure of every electrolytic cap there is along with a few HV zeners to boot.
However the good news is that there are a whole bunch of similar, newer (5 to 10 years old or newer), 20MHz scopes that can be had in that range and less, and that are basically the same under the skin--being based on a LG/Instek design that has been around for 20+ years. Check eBay for "20MHz oscilloscope" and you will find a bunch of them, some for $75.
Pick a clean newer looking instrument from Protek, Instek, Kenwood, EZ-Digital, etc.; avoid older looking B&K, Leader, Hitachi, Iwatsu, and the like that are reaching the end of their service lives...
At one time one of the early Tek 400 series scopes would my first recommendation, the 100MHz 465 being one of the best being great deals in that price range, however they are now all 30+ years old and not really viable unless you want to wade through the problems with front end attenuators, scratchy pots, and the failure of every electrolytic cap there is along with a few HV zeners to boot.
However the good news is that there are a whole bunch of similar, newer (5 to 10 years old or newer), 20MHz scopes that can be had in that range and less, and that are basically the same under the skin--being based on a LG/Instek design that has been around for 20+ years. Check eBay for "20MHz oscilloscope" and you will find a bunch of them, some for $75.
Pick a clean newer looking instrument from Protek, Instek, Kenwood, EZ-Digital, etc.; avoid older looking B&K, Leader, Hitachi, Iwatsu, and the like that are reaching the end of their service lives...
How about a picoscope? It's a PC based oscilloscope that does a lot more.
"If you buy a traditional oscilloscope, you get an oscilloscope. Buy a traditional spectrum analyzer, you get a spectrum analyzer. Buy a traditional waveform generator, you get a waveform generator. Buy a PicoScope USB Oscilloscope and – thanks to power of PicoScope – you can get an oscilloscope, spectrum analyzer and signal/waveform generator all in one. (With PicoScope’s ability to continuously stream data you can even use your oscilloscope for data acquisition.)" - taken from the picscope website
"If you buy a traditional oscilloscope, you get an oscilloscope. Buy a traditional spectrum analyzer, you get a spectrum analyzer. Buy a traditional waveform generator, you get a waveform generator. Buy a PicoScope USB Oscilloscope and – thanks to power of PicoScope – you can get an oscilloscope, spectrum analyzer and signal/waveform generator all in one. (With PicoScope’s ability to continuously stream data you can even use your oscilloscope for data acquisition.)" - taken from the picscope website
If your buying second hand the ebay is a better bet.
Some of the companies selling second hand stuff want a lot of money for them despite many being very old. I got caught out with a £200 scope that turned out to be 20 years old ! It had faults each time i got it back and they gave up in the end and refunded me.
In the end I got a scope off ebay for £60 and it has been no trouble at all for about 5 years.
Some of the companies selling second hand stuff want a lot of money for them despite many being very old. I got caught out with a £200 scope that turned out to be 20 years old ! It had faults each time i got it back and they gave up in the end and refunded me.
In the end I got a scope off ebay for £60 and it has been no trouble at all for about 5 years.
Last edited:
In the PC soundcard realm, heres some free links. The first is a simply awesome audio spectrum analyzer that's the nicest hunk of freeware I've ever seen.
DL4YHF's Audio Spectrum Analyser
Soundcard Scope
Downloads - Oscilloscope for Windows (Zelscope)
Downloads - BIP Electronics Lab Oscilloscope - 3.0
Doc
DL4YHF's Audio Spectrum Analyser
Soundcard Scope
Downloads - Oscilloscope for Windows (Zelscope)
Downloads - BIP Electronics Lab Oscilloscope - 3.0
Doc
There is no way I would connect external audio equipment to my pc, I would be worried a fault on the amp would blow up the pc.
Scopes generally cope with high voltages. Unless your like me and accidentally poke 25,000 volts from a car ignition coil into it !
That's where input attenuators come in. But for simplicity just a back to back zener diode clamp accross the input won't measurably affect things at all and will hard clamp any excessive voltages. Preceed that through a resistor with an NE-2 bulb accross input for those inclined to try reading ignition system outputs.
But for further safety try this:
Virtual 5.1-Surround USB 2.0 External Sound Card - Free Shipping - DealExtreme
Doc
But for further safety try this:
Virtual 5.1-Surround USB 2.0 External Sound Card - Free Shipping - DealExtreme
Doc
Last edited:
Buy a tektronix on ebay. For your budget you can get a working 100Mhz dual trace. Like the Tek 465 in this photo (that Google found)
http://www.bcae1.com/repairbasicsforbcae1/images/PIC00004b.jpg
These Tek scopes where the "standard" of the service industry for years. I think they sold new for about $3,500
yeah I have to agree. for a first time scope,you want a tool that works, is easy to use. no hassles and messing around with soundcards and PC's and that's just a lot of mess. then you probe the wrong spot and poof no more soundcard....stick to a true scope. they are not that expensive! good tools make all the difference sometimes!
He wanted cheap. I first suggested a real used scope... then a free one.
The problem with 465's nowadays is finding one with a good jug. That's why I suggested the 2200/2400 series. Not likely to find a 2400 series for $200... but hey, one can hope.
Doc
The problem with 465's nowadays is finding one with a good jug. That's why I suggested the 2200/2400 series. Not likely to find a 2400 series for $200... but hey, one can hope.
Doc
The trick with buying a 465 on eBay is to know the seller's code words:
"I don't know anything about these" means "it's broken"
"no returns" means "it's broken"
"it powers up" means "it's broken"
Get the idea. Find a scope where the seller says "it works fine" and just as importantly shows a photo of some kind of trace on the screen.
THere are 100+ of these scopes that come up on eBay. Wait for the right one and don't over bid. It will take a while. If you can't wait then you need a larger budget.
Check for amateur radio swap meets in your area. Often a great source of parts and test equipment. Just beware of guys who are so desperate to downsize that if you touch something, it's yours. At the end of the day, a lot of unsold treasures are heaved in the nearest dumpster. If the local ham club has a newsletter or classifieds online, you may find test gear advertised there.
I think it's well worth building some kind of isolated or protected input buffer for a sound card. It's not like you have to use a computer that's worth anything - a P2 ought to be fine. If 48k samples/sec is good enough, plenty of free sound cards should work. For higher sample rates, I believe the Audigiy 2 family allows recording at 96 and 192k; I recently got one of those used off eBay for about $25. For compete isolation, add a Toslink receiver (if the card doesn't have one), and plug in an outboard ADC. On eBay there's a "RCA Stereo To Digital Optical Coax S/PDIF Converter" which samples at 16/48k, and runs off 5V so you could run it from 4 NiMH and have complete optical isolation. This looks ideal; 24 bits, up to 192k, and only 40 Euros. 24-Bit-Audio-A/D-Wandler AAD24 | ELV-Elektronik
I think it's well worth building some kind of isolated or protected input buffer for a sound card. It's not like you have to use a computer that's worth anything - a P2 ought to be fine. If 48k samples/sec is good enough, plenty of free sound cards should work. For higher sample rates, I believe the Audigiy 2 family allows recording at 96 and 192k; I recently got one of those used off eBay for about $25. For compete isolation, add a Toslink receiver (if the card doesn't have one), and plug in an outboard ADC. On eBay there's a "RCA Stereo To Digital Optical Coax S/PDIF Converter" which samples at 16/48k, and runs off 5V so you could run it from 4 NiMH and have complete optical isolation. This looks ideal; 24 bits, up to 192k, and only 40 Euros. 24-Bit-Audio-A/D-Wandler AAD24 | ELV-Elektronik
The above ideas worth doing but does not compare with owning a "real" scope. For one thing how does one measure a 24 volt sine wive with a sound card? Don't even think about vacuum tube circuits that run on 450 volts DC. Also the input impedance of a sound card is on the order of about 20K. Some have "instrument" inputs (for a guitar) that are 1M but that is still not at all like a 10X scope probe. the sound card will "load" the circuit.
And what about "ultra sonics" sometimes the bug you are hunting is oscillation at radio frequency or transients
I have both setups. The computer is good for doing things lie an FFT of an amp's output but I have to set up the levels just right. My Tek scope is far better for debugging. The computer is better for analysis like computing harmonic distortion.
And what about "ultra sonics" sometimes the bug you are hunting is oscillation at radio frequency or transients
I have both setups. The computer is good for doing things lie an FFT of an amp's output but I have to set up the levels just right. My Tek scope is far better for debugging. The computer is better for analysis like computing harmonic distortion.
Last edited:
Anymore Tek models to be looking for in this price range for the rest of us looking to buy a scope?
Assuming bench vs cart models:
2200 series, TM scopes SC504, SC502, The telequipment line. I'd avoid the 5000 series as they're problematic with brittlized plastic problems. The small Sony-tek and 200 series are so rare and usefull people just hang onto them. If you don't mind a BIG beast the 7700-7900 series are great. If you can find one with a good jug the 465's were basically an industry standard. I even fire up my old 454 now and then, but they have nuvistor amps and finding one with a good jug is doubtful.
Try to get a screenshot of any old scope. Trace should be easily visible with speed at full crank with 10x multiplier. Even at slower speeds trace should be sharp. A fuzzy trace is the symptom of a gassy CRT. A faint trace symptom of cathode material loss. A defocussed bloom will help you spot any crt burn spots (show up as a steady dark spot) Request images of each channel functioning. Not hard to do as most all have built in calibrators.
Doc
2200 series, TM scopes SC504, SC502, The telequipment line. I'd avoid the 5000 series as they're problematic with brittlized plastic problems. The small Sony-tek and 200 series are so rare and usefull people just hang onto them. If you don't mind a BIG beast the 7700-7900 series are great. If you can find one with a good jug the 465's were basically an industry standard. I even fire up my old 454 now and then, but they have nuvistor amps and finding one with a good jug is doubtful.
Try to get a screenshot of any old scope. Trace should be easily visible with speed at full crank with 10x multiplier. Even at slower speeds trace should be sharp. A fuzzy trace is the symptom of a gassy CRT. A faint trace symptom of cathode material loss. A defocussed bloom will help you spot any crt burn spots (show up as a steady dark spot) Request images of each channel functioning. Not hard to do as most all have built in calibrators.
Doc
Last edited:
junk
total utter junk
if you can try find a philips 80s transistorized unit . 10MHZ will be fine for audio . i picked mine up a PM3233 for €10
edit . philips go go go . ever taken apart a blue front philips scope ? its cast aluminium whit silver solder stuff ABS CASE gold contacts . top notch stuff . can take a heluva lotta beating . i once shorted it whitout issues accidently measuring at a +230 ac point
edit i schould have noted the scope is grounded and it set off my earth leak . philips whit red contours are not grounded ones
total utter junk
if you can try find a philips 80s transistorized unit . 10MHZ will be fine for audio . i picked mine up a PM3233 for €10
edit . philips go go go . ever taken apart a blue front philips scope ? its cast aluminium whit silver solder stuff ABS CASE gold contacts . top notch stuff . can take a heluva lotta beating . i once shorted it whitout issues accidently measuring at a +230 ac point
edit i schould have noted the scope is grounded and it set off my earth leak . philips whit red contours are not grounded ones
Last edited:
- Status
- Not open for further replies.