PC Scopes are getting popular online any experiences? would you recomend
one? any additions for example to increase voltage input?
Depends on what you mean by PC scopes. Do you
mean a hardware gadget that interfaces to the PC?
Or something that uses your existing sound card?
As the author of Daqarta for DOS (and the upcoming
Daqarta for Windows), I can say that sound card
systems (like Daqarta) can never be a complete
replacement for a benchtop scope, because they
have limited sample rates that confine them to
audio-range work. However, if you are doing
work in this range they can be very useful for
things like spectral analysis and synchronous
signal averaging for noise reduction. These are
things that are available on pricier benchtop scopes,
but not on the entry-level models you are likely
to find. So one approach is to get a cheap benchtop
scope for high-frequency and digital work, and
use a sound card system for audio work.
With a sound card scope you can measure audio
distortion better than many expensive benchtop
units, simply because souond cards have 16-bit
ADCs and many high-frequency benchtops and
PC hardware add-ons are only 8-bit. It is *so*
nice to be able to make tweaks to an amp or oscillator
and watch what happens to the distortion as you
adjust a pot in real-time.
Another advantage of sound cards is that they
make outstanding audio signal generators, both
for things like the above distortion measurements,
or just general testing. (You may want to check out
my free DaqGen for Windows; it's only a signal
generator, but it does all sorts of waveforms and
modulation tricks.)
One downside of sound cards is that they don't
go down to DC. If you don't mind a little wiring
job, you can make your own 8-bit "sound card"
for Daqarta for DOS that uses the LPTX driver.
This circuit is typically a handful of resistors that
you plug into the printer port. It goes down to
DC and samples at up to 50 kHz.
As far as increasing the input voltage range,
you can do that on any scope, either benchtop,
PC add-on, or sound card, using voltage dividers.
Best regards.
Bob Masta
dqatechATdaqartaDOTcom
D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Home of DaqGen, the FREEWARE signal generator
