'scope terminology

[Adam Stouffer]

Hello all, I'm in the process of trying to decide what type of scope to
buy for audio work. What is the correct term to descibe analog scopes
that display the numeric readings right on the screen? Say for example
it will show you have a 3vPP signal and the freq is 12Khz? I know the
digitizing scopes all do this but only a few analog models seem to.

Is an old digitizing scope like a HP 54501A or 54200A overkill for doing
audio work, or should I stick to analog? Any input appreciated.


Adam

 

[Walter Harley]

"Adam Stouffer" <adam_stouffer@hotmail.com> wrote in message
news:yEiGc.21283$6e7.11228@nwrddc03.gnilink.net...

Hello all, I'm in the process of trying to decide what type of scope to
buy for audio work. What is the correct term to descibe analog scopes
that display the numeric readings right on the screen? Say for example
it will show you have a 3vPP signal and the freq is 12Khz? I know the
digitizing scopes all do this but only a few analog models seem to.

Is an old digitizing scope like a HP 54501A or 54200A overkill for doing
audio work, or should I stick to analog? Any input appreciated.

You might need to be more specific about what you mean by "audio work."

For repairing hifi amps, any old 20MHz dual-trace scope will do fine - you
can probably find something on eBay for less than $100. Couple that with a
cheap multimeter and a frequency counter (or a calculator) and you'll be in
great shape. The cursor features you describe are nice (I use 'em on my
2465A) but not by any means necessary.

For designing very-low-distortion circuitry, in conjunction with a
distortion analyzer, a digitizing scope can allow you to average a wave over
many repetitions and thus see (repetitive) distortion buried in (random)
noise. Some will also do FFT's, so you don't need a spectrum analyzer. (Or
a sound card and computer.)

 

[TekMan]

Adam Stouffer <adam_stouffer@hotmail.com> wrote in message news:<yEiGc.21283$6e7.11228@nwrddc03.gnilink.net>...

Hello all, I'm in the process of trying to decide what type of scope to
buy for audio work. What is the correct term to descibe analog scopes
that display the numeric readings right on the screen? Say for example
it will show you have a 3vPP signal and the freq is 12Khz? I know the
digitizing scopes all do this but only a few analog models seem to.

Is an old digitizing scope like a HP 54501A or 54200A overkill for doing
audio work, or should I stick to analog? Any input appreciated.


Adam

hi adam,

if you stay in audio work, a low-end bandwith (BW) scope ist still
perfect (e.g the 1 MHz models old tek 5403 with plugins).
But if you like to stay in electronics, your interest in higher BW
will steadily increase.
So I'd recommend to look for a BW with 50 or 100 MHz right from the
start. If you stay with tek, a 455 (50 MHz) or 465 (100MHz) is a nice
sturdy portable. In europe appr. 80 to 200 euros. US you have to chk
the prices yourslef, or look for what other contributors say.

for hp scopes: a 1740A is old but still a good workhorse. just my 2
cts.

all above are analogue scopes. I ve not needed digital ones for my
audio work. But if you want: with a 54501A or similar, you can do the
job too.
digital storge is seldom needed. If you think you really need it,
take a look at the european brand Hameg too: The older HM205-3 is a 20
MHz BHz "analog-digatl" scope. That means you can swithc between both
modes with a click of a switch. The A/D has 40 MSamples/sec, so that's
more than enough fpor audio.

These hamegs are quite cheap, and do the job well for hobbists work.

hth,
Andreas