OT: scope recommendations?

[Jim Yanik]

bok118@zonnet.nl (Gerard Bok) wrote in
news:4d2acc1c.1098526@News.Individual.NET:

On Mon, 10 Jan 2011 00:58:42 -0500, "Michael A. Terrell"
mike.terrell@earthlink.net> wrote:


Gerard Bok wrote:

On Sun, 9 Jan 2011 12:48:40 -0000, "N_Cook" <diverse@tcp.co.uk
wrote:

Gerard Bok <bok118@zonnet.nl> wrote in message
news:4d286e4d.3071872@News.Individual.NET...
On Fri, 07 Jan 2011 06:24:12 -0800, Smitty Two
prestwhich@earthlink.net> wrote:

A friend is being coerced by circumstance into learning a bit of
electronics, and has need for a basic scope.

For basics, I would advice him to run a soundcard-as-scope
program on his PC. Freeware widely available and suitable for
basic stuff.
Let him note the limitations he observes and that will give him
his 'shopping list' when buying a real scope.

I've never used a pc scope - is it easy for a novice (or absent
minded old-hand) putting the probe where he shouldn't and blowing
up the whole pc , not just the input FETs

What's cheaper, blowing a scope's input FETs or blowing a PC's
soundcard ? And what's easier to repair / replace ?
Imho scopes are both less foolproof and less forgiving than PCs.

You may not agree, but I stand by my advice.
I can only add, that --indeed-- some folks shouldn't be allowed
to be to close to anything that has wires attached.
For those folks: learn electronics by books only, don't try hands
on ;-)


How many scopes have you blown up? I've used them for 45 years and
never blown up the input on one.

I've never blown a scope
But N_Cook was worried someone would

I've replaced a lot of blown input FET pairs on TEK scopes.
also several melted input BNCs.

and replaced countless power cords that had their ground pin cut off.

--
Jim Yanik
jyanik
at
localnet
dot com

 

[Michael A. Terrell]

Gerard Bok wrote:

On Mon, 10 Jan 2011 00:58:42 -0500, "Michael A. Terrell"
mike.terrell@earthlink.net> wrote:


Gerard Bok wrote:

On Sun, 9 Jan 2011 12:48:40 -0000, "N_Cook" <diverse@tcp.co.uk
wrote:

Gerard Bok <bok118@zonnet.nl> wrote in message
news:4d286e4d.3071872@News.Individual.NET...
On Fri, 07 Jan 2011 06:24:12 -0800, Smitty Two
prestwhich@earthlink.net> wrote:

A friend is being coerced by circumstance into learning a bit of
electronics, and has need for a basic scope.

For basics, I would advice him to run a soundcard-as-scope
program on his PC. Freeware widely available and suitable for
basic stuff.
Let him note the limitations he observes and that will give him
his 'shopping list' when buying a real scope.

I've never used a pc scope - is it easy for a novice (or absent minded
old-hand) putting the probe where he shouldn't and blowing up the whole pc ,
not just the input FETs

What's cheaper, blowing a scope's input FETs or blowing a PC's
soundcard ? And what's easier to repair / replace ?
Imho scopes are both less foolproof and less forgiving than PCs.

You may not agree, but I stand by my advice.
I can only add, that --indeed-- some folks shouldn't be allowed
to be to close to anything that has wires attached.
For those folks: learn electronics by books only, don't try hands
on ;-)


How many scopes have you blown up? I've used them for 45 years and
never blown up the input on one.

I've never blown a scope
But N_Cook was worried someone would

Him, I can understand.

I've repaired a lot of scopes, put they were mostly bad transformers
or power supplies. I saw a lot of bad resistors in the Focus/Intensity
circuit on cheap scopes too.


--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

 

[Smitty Two]

In article <4d2acac2.751936@News.Individual.NET>,
bok118@zonnet.nl (Gerard Bok) wrote:

On Sun, 09 Jan 2011 13:55:13 -0800, Smitty Two
prestwhich@earthlink.net> wrote:

In article <igcvde$muj$1@news.eternal-september.org>,
mike <spamme9@gmail.com> wrote:

Not clear how the strobe improves on the flash of light you get from the
shutter in the projector???

One problem with using off-the-shelf projectors, as he has been doing
for many years, is duty cycle.

From what I read here, I would suggest your friend to put the
frame scan setup aside for a while and investigate the use of a
linescanner.

What's a linescanner?

That will allow him to ditch the jumpy filmtransport altogether
and scan the film right upto the maximum (continuous) speed his
electronics can handle and convert.
(That's the very same way some old microfilmscanners operated

 

[Smitty Two]

In article <igef0a$4fc$1@news.eternal-september.org>,
"N_Cook" <diverse@tcp.co.uk> wrote:

Am I missing something here - why real time speed of 24 fps or whatever for
8mm.
Slow it right down and software to convert to real time colour correction
/scratch "removal" etc , audio synced in off realtime or speeded up
separately .

I'm not understanding this. He definitely doesn't want to slow the film
down; he usually runs it at 2x. Your second sentence doesn't grok.

 

[Smitty Two]

In article <djeei65go3b9sa9p3rb0mku609jfef5usi@4ax.com>,
Rich Webb <bbew.ar@mapson.nozirev.ten> wrote:

PC-based USB-interfaced 'scopes tend not to have stellar sample rates.
There's usually a note in the fine print that the advertised sample rate
is "equivalent time sampling" which is okay for repetitive waveforms but
not so much for single event captures -- and single events are one of
the nice things you get with digital scopes.

Noted, thanks.

GW Instek and Rigol each have reasonably-priced 100 MHz, 1 Gsps dual
channel models that could be a starting point for comparison
http://www.tequipment.net/InstekGDS-2102.html
http://www.tequipment.net/RigolDS1102E.html

A tad spendy for his needs and budgets, but I appreciate the suggestions.

 

[Smitty Two]

In article <Xns9E68B2E5858BAjyaniklocalnetcom@216.168.3.44>,
Jim Yanik <jyanik@abuse.gov> wrote:

I'd go for a TEK low end LCD scope,for a new model. TDS2200?

for a beginner on a tight budget,maybe a T922/T932/T935,those can be had
very inexpensively,are simple to operate.

Thanks, I'll look into those. Seems like a good fit for him.

 

[Jeffrey Angus]

On 1/9/2011 4:33 PM, Jim Yanik wrote:

for a beginner on a tight budget,maybe a T922/T932/T935,
those can be had very inexpensively,are simple to operate.

Weren't those the ones made as a joint effort with Sony?
Sort of Tek's experiment with bottom feeding?

Not good enough for the lab and too expensive for the shop.

Jeff

 

[George Herold]

On Jan 11, 8:38 am, Smitty Two <prestwh...@earthlink.net> wrote:

In article <djeei65go3b9sa9p3rb0mku609jfef5...@4ax.com>,
 Rich Webb <bbew...@mapson.nozirev.ten> wrote:



PC-based USB-interfaced 'scopes tend not to have stellar sample rates.
There's usually a note in the fine print that the advertised sample rate
is "equivalent time sampling" which is okay for repetitive waveforms but
not so much for single event captures -- and single events are one of
the nice things you get with digital scopes.

Noted, thanks.



GW Instek and Rigol each have reasonably-priced 100 MHz, 1 Gsps dual
channel models that could be a starting point for comparison
http://www.tequipment.net/InstekGDS-2102.html
http://www.tequipment.net/RigolDS1102E.html

A tad spendy for his needs and budgets, but I appreciate the suggestions.

I've got a 50MHz Rigol that I like. DS1052. $400.00

We bought OWON for a bit less, But I would stay away from that one.

George H.

 

[josephkk]

On Tue, 11 Jan 2011 05:35:41 -0800, Smitty Two <prestwhich@earthlink.net>
wrote:

In article <4d2acac2.751936@News.Individual.NET>,
bok118@zonnet.nl (Gerard Bok) wrote:

On Sun, 09 Jan 2011 13:55:13 -0800, Smitty Two
prestwhich@earthlink.net> wrote:

In article <igcvde$muj$1@news.eternal-september.org>,
mike <spamme9@gmail.com> wrote:

Not clear how the strobe improves on the flash of light you get from the
shutter in the projector???

One problem with using off-the-shelf projectors, as he has been doing
for many years, is duty cycle.

From what I read here, I would suggest your friend to put the
frame scan setup aside for a while and investigate the use of a
linescanner.

What's a linescanner?

That will allow him to ditch the jumpy filmtransport altogether
and scan the film right upto the maximum (continuous) speed his
electronics can handle and convert.
(That's the very same way some old microfilmscanners operated

Basically it captures one line at a time. Step and repeat for umpty
hundred (or few thousand) lines to get a frame. The same counters that
align the framing are used here as well. Continuous lamp focused as a
line (or special and expensive "line lamp").