I received my Bitscope BS310U a couple of weeks ago. The next day I took
it up to Mark Supinski's hangar. Paul & I had fits trying to figure it
out with the BADLY out of date manual that came with it. The problem we
had was expecting it to act like a regular 'scope, where you have to
figure out a bunch of parameters. We were making too hard a job of it.
It isn't like that, pretty much plug and play. Auto range, auto trigger
(mostly), auto centering. All these auto thingies can be adjusted or
over-ridden if they don't suit.
Attached are two traces I captured using the Dso (stands for digital
storage oscilloscope) Bitscope application on my Linux Fedora 7 laptop.
The input was the RX7 crank angle sensor lying on my desk - I spun it by
hand. Channel A (the yellow line on the trace) is connected to the 2X
pulses per revolution sensor. Channel B (the green line on the trace) is
connected to the sensor associated with the 24 tooth gear below the 2X
rotor which should produce 24 pulses per revolution if my understanding
is correct.
The labels under the traces tell you how much time is between vertical
graduations and how much voltage between the horizontal graduations.
There are other parameters also, but these are the important ones. For a
full explanation go to
http://www.bitscope.com.
By default, the screen shows only half of the data capture. You can see
the rest by manipulating the slider under the window.
One of the captures includes both the frequency domain and the time
domain. The top half of the 'scope window is the frequency domain
analysis. The bottom half is the time domain trace.
I don't know why the traces look the way they do - noise and multiple
pulses. I suspect that this CAS is not working properly. And there is
nothing much coming in from the 24X sensor. OOPS, I just noticed that
the B channel probe was set on 10X attenuation. But still, it doesn't
look like there is much there.
What do I think of this gadget? WOW! IMHO it can't be beat for the price
if you have a laptop or other computer that you can use with it. What's
wrong with it? Well, regarding the hardware and software, not much. The
only problem I have found to date is the out of date printed manual, and
the recent one is too general. I could have used some how-to hand
holding. Part of my problem is that I stopped being an electronics
technician in 1963. Just slightly behind the times! :)
If you order this little jewel, the first thing you need to do is throw
away the printed document that comes with it. Judging from the one I
got, it is seriously out of date. The CD that comes with it has an up to
date manual in pdf form. Unfortunately it covers all their scope
products so some of the illustrations don't necessarily reflect your
model. It also comes with the software on a CD.
If you download the Dso application and load it on your computer (both
Windoze and Linux are supported) you can play with the bitscope
connected to the internet! Is that neat or what? The only thing you
can't do is change the signal inputs. They also have some traces stored
that you can download. And a bunch of other stuff on their download
page. All of the downloads are free. :)
NOTE: the bitscope does not include probes unless you order them in
addition to the bitscope itself. If you already have probes, you won't
need to order any because the bitscope takes standard probes. I didn't
notice this when I ordered the bitscope, so there were no probes. But
this turned out really fine. I got my probes from Probe Master
(
http://www.probemaster.com) The 3900 series is adequate for the
bitscope (only 50mHz BW) but I got 3 (2 1x-10x and 1 100x) of the 4900
series because they accept all the neat tip accessories. Take a look at
the 17 piece kit for a good variety of probe tips.
For automotive/aircraft and PICAXE (4MHz clock) use, the 50MHz band
width of the bitscope is plenty good.
Be aware of the capture time. If you select a long time base and lots of
samples, the capture time can get long - maybe on the order of 10
seconds. The window in the capture area will tell you. During this
capture period it might seem like nothing is happening, because the
screen only shows the first part of the capture. It took me a quite a
while to discover this, but the light finally dawned.
Hope this helps someone.
My signature is different because I haven't figured out how to change it
in Fedora7. Later.
Cheers,
Doc Custer
No attachment Doc. What happened? :)
The signature text file is usually in root.
Paul Lamar ...No rotor no motor.
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