which digital oscilloscope

[echo44]

I was looking at the techtronix web site and there are so many options?
For guitar amp work I figure 100MHZ is more than adequate
than there is th equestion of 2 inputs vs 4 inputs?
Would I ever need "active probes"?
sample rates I was looking at 1GHZ vs 2.5GHZ
The textronix rep said her amp building friend prefers the model
with a 1MP record length?
Howvever The 1MP record lenghth is more money and the sample rate is slower 1GHZ vs 2.5 GHZ if I went with 2.5GHZ and a 1MP record lenghth the scope would be over
$3000. Any advice would be appreciated
I currently am comparing the DPO20129( $1870) vs the TDS2012c($1300)

[steve_p]

If you are looking in that price range, I would suggest that you check out the Agilent offerings as well.
We just picked up an Agilent DSOX2004A which is an awesome scope.
This is the 4 channel, but they make a 2 channel around 1200 as well.
Most options are software upgradable, including adding built in function generator, bandwidth upgrades..etc.
Very nice scope for the money.

Steve

[Phil_S]

I have been told for guitar amp work 20MHz is more than adequate, thought I doubt many modern scopes are designed to such a "low" upper end. Are you sure you want to spend that much? There is nothing wrong with buying high quality stuff, if that's what you want. Maybe you can save several hundred dollars and get two great tools instead of one?

[selloutrr]

IMHO the rep was trying to make a conmission and say sucker all over. Or not knowing pointing to the flagship model with more features is often the easiest way of making a customer happy.

In daily life you wont being using 90% of what that unit can do.

You don't need more the 20Mhz for traditional guitar amp repair/building.
Dual ch is fine.
You should be able to purchase a quality scope for a few hundred dollars.

You may need a higher Mhz if you start working on the computer inside modeling amplifiers but you would also need a rework station,a static free work area, and wave solder setup. which becomes prohibitive quick. Even the manufactures pull the boards and replace them it's not cost effect to repair them. As a service center they would supply you with the parts, if you could even just narrow the problem to being on that board. Again making the scope no longer needed.

In my experience anything that does more then one thing doesn't do multiple things as well as a dedicated device. meaning an all in one tester most likely wont give you what stand alone pieces will. The first example that comes to mind is the ability to run more then a couple or one feature at a time.

[Kazooman]

I posted a question about a week ago asking for opinions on a used scope on ebay. The responses I received here (and on another forum) led me to abandon that opportunity. I did quite a bit of research and ordered a scope yesterday. I chose a Rigol DS1052E. You can see a video of the internals here:

http://www.tequipment.net/RigolIndepend ... 399content

Specs and a good price here:

http://www.tequipment.net/RigolDS1052E.html

In fact, they dropped the price $20 overnight! It is now $329.

I think this will meet my needs and then some.

[surfsup]

I ordered an Atten ADS1062CAL for $350. Very nice scope...

To use it I have a PC with a DAW setup to play a free downloaded 1kHz sample tone file. I also have 100Hz, 440Hz, 2kHz, and 5kHz to see the different frequency responses. But to use a scope you need to be able to send a consistent signal into the amp.

Also, to not piss off everyone within 1000 yards, you need a dummy load because 1kHz tone signals are LOUD!

[echo44]

So I am guessing this would be overkill
http://www.tek.com/tekstore/configure/MSO72004C
you could buy a house for that much

[markr14850]

Nice piece of equipment... It can accurately measure mojo to five decimal places.

[Kazooman]

An update on my scope. I sent them a message noting the reduced price and they immediately responded that they would refund the difference. Seems like a good place to shop.

I found a freeware PC signal generator here:

www.dr-jordan-design.de/signalgen.htm

They have a "pro" version that has more options enabled as well as several other software packages.

The output is continuously variable from 20 - 20,000 Hz. It also has a built in attenuator so you can easily control the output level. The freeware version gives you sine, square, and triangular wave choices as well as white noise. I don't have my scope yet to give you an opinion on the quality of the signals, but the screen shots in the pdf instruction manual make them look pretty good.

With the Pro version you can load a large number of frequency presets so you can change with a mouse click. It also offers sine wave sweeps (variable between two frequencies you set at an adjustable rate. Lots of other bells and whistles.

If I am happy with the performance once I can check it with the scope I will probably purchase the upgrade to support the guy (and for the utility).

[NickC]

I got a used, and fully calibrated (stamped by authorized lab), Tektronix 485 (with set of probes included) from eBay for a very good value. Very happy with it.

[markr14850]

The analog oscilloscope varying voltages ...

Moderator please.

This is just a spambot trying to raise his google page ranking by including a link to his website in his signature.

[rdjones]

The analog oscilloscope varying voltages ...

Moderator please.

This is just a spambot trying to raise his google page ranking by including a link to his website in his signature.

I sent "Kyle" a pm on Dec 27, it has never read it.

rd