Superpositioned: New Oscilloscope: Instek GDS-820C

New Oscilloscope: Instek GDS-820C

Matthew — Tue, 04 Apr 2006 15:32:00 -0700

If you know me on a more personal basis, then you know that I have been experiencing some issues with several projects/articles in the works for this site. Up until now, I did not have my own oscilloscope. Usually I am able to make due, but recently it has been making things harder than it is worth.

After some research I happened to find a deal on a new Instek GDS-820C DSO. The offer was impossible to refuse and cheaper than the GDS-805C. Besides the obvious increase in sample rate, the GDS-820C comes standard with USB and parallel ports along with the RS-232 port, but GBIP is still only an option. These digital storage options will allow me to post pretty pictures on the blog!

This oscilloscope samples at 100MSamp/sec and is capable of 150mHz operation. They claim an ‘effective’ sampling rate of 25GSamp/sec when viewing repetitive signals. In comparison, Tektronix base model samples at rates up to 1GSamp/sec.

At 150mHz it will be hard to see much if the signals are not repetitive! If you know anything about Shannon’s Sampling Theorem, the effective sampling rate makes 150mHz operation seem… possible. Without this hack, the scope would be limited to half the sampling frequency or 50mHz. I could have paid more for a Tektronix scope, but the hardware would have been limited to 40mHz, mono anyway. This will suit my needs.

Update: If you view a signal sampled at over 100MSamp/sec, then you can tell it is making due with the effective sampling rate. I am not sure if this really matters because I do not have access to signal over a MHz at the moment.

"New Oscilloscope: Instek GDS-820C" by Tom Ferge

Wed, 23 Aug 2006 06:29:19 -0700

Where did you get this from for $600.00 and it is a quality line product as far as sampling and accuracy and ease .thanks tom

"New Oscilloscope: Instek GDS-820C" by Abestel

Thu, 18 May 2006 08:13:51 -0700

finally something i can afford. amazing price.

"New Oscilloscope: Instek GDS-820C" by Matthew

Mon, 17 Apr 2006 19:07:06 -0700

I must admit that I have not used it much. There are also a severe lack of reviews on the Internet, and I do not have much to compare it to other than old Tektronix scopes.

I had never used a LCD before, and if a standard scope with digital storage was nearly as affordable, then I would have bought that. Being used to analog scopes, I don’t like the repetitive signal sampling. Although, it does its job perfectly. Squeezing in 20 times the bandwidth isn’t something I should complain about.

"New Oscilloscope: Instek GDS-820C" by Russell

Mon, 17 Apr 2006 01:25:35 -0700

I’m considering purchasing the same scope. Are you happy with it so far?

"New Oscilloscope: Instek GDS-820C" by Matthew

Thu, 06 Apr 2006 12:26:49 -0700

Yes! It is sitting in my ‘lab.’ For a grand total of about $600. I can not explain the feeling of owning your own scope.

I would have taken a real picture, but my digital camera did not do it any justice. Maybe I will post one on my personal blog later today.

"New Oscilloscope: Instek GDS-820C" by Greg Lipscomb

Thu, 06 Apr 2006 10:42:49 -0700

Hey, That is an awesome oscilloscope. Are you actually going to get it?