Author Topic: DSO138, Not Even Once  (Read 367 times)

Offline Mads Barnkob

  • Administrator
  • High Voltage Expert
  • *****
  • Posts: 1264
  • Karma: +18/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
DSO138, Not Even Once
« on: January 20, 2020, 11:13:23 AM »
Before you buy a DSO138 or DSO150 from ebay, amazon, wish or aliexpress, it is important to understand what you are getting. The specifications are very loosely written and what looks good on paper is useless in practical use. Here I test the DSO138 specified at 200 kHz, but in reality it is worthless above 20 kHz.

Buying the right oscilloscope is knowing your work area limits and where it might be in the future. I recommend that you read: 12 things to consider when choosing an oscilloscope: https://www.mouser.com/pdfdocs/Tektronix12_things_to_consider1.pdf

For the Nyquist applet to play with: http://195.134.76.37/applets/AppletNyquist/Appl_Nyquist2.html

« Last Edit: January 20, 2020, 08:17:30 PM by Mads Barnkob »
http://www.kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics

Offline Twospoons

  • High Voltage Enthusiast
  • *
  • Posts: 28
  • Karma: +0/-0
    • View Profile
Re: DSO138, Not Even Once
« Reply #1 on: January 20, 2020, 08:31:54 PM »
At that price , what else would you expect?
And quite frankly I'd consider anything under 20MHz bw to be useless.

Offline klugesmith

  • High Voltage Technician
  • ***
  • Posts: 131
  • Karma: +5/-0
    • View Profile
Re: DSO138, Not Even Once
« Reply #2 on: January 20, 2020, 11:10:05 PM »
Depends on what you're trying to capture.
20 MHz could be plenty fast for watching a detector:

In fact, selectable bandwidth reduction (by digital filtering) is a valuable feature in fast DSO's.
Easy way to reduce noise when the noise is unimportant.
« Last Edit: January 21, 2020, 08:19:44 PM by klugesmith »

Offline Mads Barnkob

  • Administrator
  • High Voltage Expert
  • *****
  • Posts: 1264
  • Karma: +18/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
Re: DSO138, Not Even Once
« Reply #3 on: January 21, 2020, 08:37:14 AM »
At that price , what else would you expect?
And quite frankly I'd consider anything under 20MHz bw to be useless.

It is not so much what I expect, but what many first builders of a Tesla coil expects. I have gotten too many emails and messages about distorted wave forms measured with these toy scopes, that was my inspiration to make this video :)
http://www.kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics

Offline Mysteriousduck

  • High Voltage Enthusiast
  • *
  • Posts: 5
  • Karma: +0/-0
    • View Profile
Re: DSO138, Not Even Once
« Reply #4 on: January 21, 2020, 03:49:24 PM »
Ah, yes I've seen these. They seem like more of a toy, but I'm sure they are great for kids/beginners that want to get practice putting components together and probing simple circuits.

Any thoughts on this lil pup? Good way to spend $100 for a beginning hobbyist, or would the money be better spent on a used bench scope?

Signstek Nano ARM DS212
https://www.amazon.com/gp/product/B00HEZKY28/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

Offline Mads Barnkob

  • Administrator
  • High Voltage Expert
  • *****
  • Posts: 1264
  • Karma: +18/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
Re: DSO138, Not Even Once
« Reply #5 on: January 21, 2020, 08:05:20 PM »
Ah, yes I've seen these. They seem like more of a toy, but I'm sure they are great for kids/beginners that want to get practice putting components together and probing simple circuits.

Any thoughts on this lil pup? Good way to spend $100 for a beginning hobbyist, or would the money be better spent on a used bench scope?

Signstek Nano ARM DS212
https://www.amazon.com/gp/product/B00HEZKY28/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

It is better than the DSO138, but it certainly is not worth 107$ from the specifications, maybe the size of it is worth it, if you can live with the limitations.

Signstek DS212 (107$):

0.0093 MHz/$
0.093 MSas/$
? data points/$

Rigol DS1052e (230$):
0.217 MHz/$
4.347 MSas/$
4347 data points/$

If you are looking to spend 100$ on a DSO, its better to spend 200$+ and get a real DSO.

Old used analog 20 MHz scopes should not be more than 10-20$ at a HAM market
http://www.kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics

Offline Twospoons

  • High Voltage Enthusiast
  • *
  • Posts: 28
  • Karma: +0/-0
    • View Profile
Re: DSO138, Not Even Once
« Reply #6 on: January 21, 2020, 10:54:44 PM »
Old used analog 20 MHz scopes should not be more than 10-20$ at a HAM market

Thats the thing isn't it. If you're on a limited budget the second hand market is where you will get the best value. A lot of that old gear is actually pretty damn good.  And for use around a TC an old analog scope is probably going to be more stable.
When I needed a spectrum analyser for a project I spent $2k on Ebay and got an '80s era TEK492. Original list price was $60k in 1985 dollars! It was a gorgeous piece of RF engineering and still worked great.

High Voltage Forum

Re: DSO138, Not Even Once
« Reply #6 on: January 21, 2020, 10:54:44 PM »

 


* Recent Topics and Posts

post Re: HP T620 thin to plus conversion....
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
Mads Barnkob
Today at 09:09:33 AM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ritaismyconscience
Today at 07:08:30 AM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
Today at 04:37:33 AM
post Re: DIY 250W LED Flood Light for High Speed Filming
[Light, Lasers and Optics]
Mads Barnkob
February 23, 2020, 09:04:34 PM
post HP T620 thin to plus conversion....
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
spacecabbie
February 23, 2020, 02:03:15 PM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ritaismyconscience
February 23, 2020, 05:43:17 AM
post Re: 230 volts spark gap
[Spark Gap Tesla Coils (SGTC)]
klugesmith
February 23, 2020, 04:07:51 AM
post Finding accelerometer location inside a phone
[Smart Phones]
haversin
February 22, 2020, 07:23:28 PM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
dj.cosmo.esq
February 22, 2020, 07:41:18 AM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ritaismyconscience
February 22, 2020, 06:49:22 AM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
February 22, 2020, 03:39:10 AM
post Re: 230 volts spark gap
[Spark Gap Tesla Coils (SGTC)]
Quentief
February 22, 2020, 02:32:55 AM
post Re: 230 volts spark gap
[Spark Gap Tesla Coils (SGTC)]
klugesmith
February 22, 2020, 02:10:34 AM
post Re: 230 volts spark gap
[Spark Gap Tesla Coils (SGTC)]
Quentief
February 22, 2020, 01:27:41 AM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Hydron
February 21, 2020, 08:00:10 PM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
February 21, 2020, 02:44:44 PM
post Re: 230 volts spark gap
[Spark Gap Tesla Coils (SGTC)]
klugesmith
February 21, 2020, 07:21:13 AM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ritaismyconscience
February 21, 2020, 06:11:32 AM
post Re: GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
February 21, 2020, 04:42:34 AM
post Re: 230 volts spark gap
[Spark Gap Tesla Coils (SGTC)]
davekni
February 21, 2020, 04:37:53 AM
post Re: UV-cured cyanoacrylate glues?
[Light, Lasers and Optics]
Twospoons
February 21, 2020, 04:28:33 AM
post Re: UV-cured cyanoacrylate glues?
[Light, Lasers and Optics]
klugesmith
February 21, 2020, 04:21:31 AM
post GDT keeps on killing IGBTs
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ritaismyconscience
February 21, 2020, 02:41:03 AM
post Re: 230 volts spark gap
[Spark Gap Tesla Coils (SGTC)]
Quentief
February 21, 2020, 12:28:20 AM
post Re: UV-cured cyanoacrylate glues?
[Light, Lasers and Optics]
Twospoons
February 20, 2020, 09:45:21 PM
post Re: UV-cured cyanoacrylate glues?
[Light, Lasers and Optics]
klugesmith
February 20, 2020, 07:28:01 PM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
Uspring
February 20, 2020, 02:06:26 PM
post Re: UV-cured cyanoacrylate glues?
[Light, Lasers and Optics]
shrad
February 20, 2020, 10:38:01 AM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
davekni
February 20, 2020, 05:14:43 AM
post Re: Is this flyback OK for my Plasma ball ?
[Transformer (Ferrite Core)]
davekni
February 20, 2020, 05:04:50 AM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
klugesmith
February 20, 2020, 04:47:41 AM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
Peregrine
February 19, 2020, 07:29:23 PM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
Peregrine
February 19, 2020, 06:47:55 PM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
Peregrine
February 19, 2020, 06:45:23 PM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
Teravolt
February 19, 2020, 06:41:42 PM
post Re: Is this flyback OK for my Plasma ball ?
[Transformer (Ferrite Core)]
John123
February 19, 2020, 06:10:34 PM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
MRMILSTAR
February 19, 2020, 05:52:20 PM
post Re: Is this flyback OK for my Plasma ball ?
[Transformer (Ferrite Core)]
ElectroXa
February 19, 2020, 05:05:50 PM
post Re: Is this flyback OK for my Plasma ball ?
[Transformer (Ferrite Core)]
John123
February 19, 2020, 04:11:22 PM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
Uspring
February 19, 2020, 02:03:12 PM
post Is this flyback OK for my Plasma ball ?
[Transformer (Ferrite Core)]
warmania
February 19, 2020, 11:24:58 AM
post Re: HP T620 Thin Client - PSU Hack And Windows PC Modification
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
latethannever
February 19, 2020, 11:00:15 AM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
rikkitikkitavi
February 19, 2020, 10:43:13 AM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
Peregrine
February 19, 2020, 06:54:14 AM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
klugesmith
February 19, 2020, 06:51:52 AM
post Re: 230 volts spark gap
[Spark Gap Tesla Coils (SGTC)]
davekni
February 19, 2020, 03:53:13 AM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
ElectroXa
February 18, 2020, 09:44:25 PM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
MRMILSTAR
February 18, 2020, 09:34:06 PM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
Peregrine
February 18, 2020, 08:27:31 PM
post Re: Help!Capacitor that burns out after a while!
[Voltage Multipliers]
Weston
February 18, 2020, 07:55:14 PM

Sitemap 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 
SimplePortal 2.3.6 © 2008-2014, SimplePortal