Good Oscilloscope?

It looks alright for analog audio. The thing I make sure of when buying off ebay is that the seller states that it is working, and guarantees against DOA, which your seller does.

But you could do better - for the same price, you could get a used tektronix scope, like the 475. It is manufacture/model that has stood the test of time, which is worth a lot. Look around here for recommended scope models, they are almost always tek scopes.
 
Unless you can get a guarantee that it's in good working order (will trigger on a signal...), it's too much for that scope. 'Not DOA' and 'in good working order' are not the same.

I agree. Tek scopes are my first choice but have been going quite high on eBay. Stay away from the 2400 series and the early LCD Tek scopes. The older 400 series (465, 465b, 453, 475... - no prefix) and the 2200 series are good scopes.

B&K also makes good scopes.
 

spooney

Member
2006-12-01 4:41 am
This one would cost me about 150 dollars shipped:http://cgi.ebay.com/ws/eBayISAPI.dl...em=310029839994&_trksid=p3984.cTODAY.m238.lVI

It says on the page that if the item has been listed as being tested that you can expect it to be in good working order. Its definitely in my price range.I've got my eye on a tektronix 465b and a tenma scope as well.Those two end tomorrow.I'm just not sure which one I want to bid on or if I just want to get this b&k .
 
This one would get my vote. It has a complex waveform locked on the display. Unless it gets damaged in shipping, it's almost certainly going to work well.

The only thing I see that could be a problem is the intensity. It's max'd out (assuming that the knob is on the shaft as it should be). This probably doesn't mean much here because the timbase is in the upper end of its range and the waveform covers much of the display. It's probably fine.

The 465B is a better scope but this one is a sure thing and will do the job.
 
The capacitance range of a probe must match the input capacitance of the scope. Most generic probes have enough range to work with most scopes.

According to the manual, the 2120b has an input capacitance of 25pF. Yours is probably about the same.

http://www.testequipmentdepot.com/bk-precision/pdf/2120b_2125a_man.pdf


You may want to look for a 1x/10x switchable probe. You can easily switch between preamp and speaker level signals without having to change the scope settings. This is one example.
http://www.pomonaelectronics.com/pdf/d6491-6501_ocs_probes_2_02.pdf