[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Velleman HPS10 Hand held digital scope?

Original poster: Chester Lowrey <hilo90mhz@xxxxxxxxx>


I dont have any experience with this particular model, but I have the
Velleman PCS500 computer oscope and it works great.. Two channels,
100mhz sampling rate, if you get the computer function generator that
velleman sells they can work together and do bode plots which are
really usefull sometimes.. They both work great and are very
functional tools.

And for the price of both models you cant beat the performance. One of
the frequency divider chips in the time base generation part of the
function generator was malfunctioning and they helped me find the
problem and sent me a new chip... so the tech support is good.

I use this scope almost every day and dont have any major complaints.
Granted id rather have one of those fancy Tek scopes, and Terry keeps
tempting me with all the screen captures of his DRSSTC ;) but those
are just a little pricey :P

Id recommend you give it a shot as long as the slow sampling rate and
single channel are adequate for your needs..

Chester Lowrey

On Fri, 04 Mar 2005 08:15:00 -0700, Tesla list <tesla@xxxxxxxxxx> wrote:
> Original poster: "Steve Conner" <steve.conner@xxxxxxxxxxx>
> hey Terry, all,
> I looked up the Velleman HPS10, Maplin here in the UK have it for ? 80 which
> is a lot cheaper than any other digital scope but still not what I'd call
> expendable. Having said that, Velleman are a small company so I expect they
> made it with off-the-shelf parts and it will be easy to get replacement
> chips if (when) the front end gets fried.
> http://www.maplin.co.uk/Media/PDFs/RS82_N10AQ%20Manual.pdf
> I looked at the manual and it seems to have only the most basic
> spit'n'sawdust features. There is no data download to a PC which is
> disappointing.
> The HPS10 has a 10MHz sampling rate and a 2MHz analog bandwidth. So the rise
> time will be about 0.4/bw which is 200ns. Therefore I wouldn't expect it to
> give an accurate picture of H-bridge switching waveforms, as Terry has shown
> waveforms with rise times in the 10s of ns and nasty 25MHz ringing. This
> scope would miss all that. But it would probably be plenty good enough for
> most things and of course the storage is a huge bonus.
> It is only single trace (there isn't a separate trigger input either) which
> is a pain for that very important function of checking the voltage and
> current in your DRSSTC primary are in phase. I guess you could still do this
> as the switching transients tend to "splash" onto the current waveform so
> you can see them.
> Velleman also make a cheaper HPS5 and a more expensive HPS40. I saw this one
> on sale for ? 300 which is getting towards the price of a second hand Tek
> TDS220.
> An even more unusual option is the GBDSO cartridge which turns a Game Boy
> into a dual trace storage scope. I don't know if the kit is on sale any
> more.
> http://www.semis.demon.co.uk/Gameboy/DsoDemo/DsoDemo.htm
> Steve C.