[Jupiter]

I'm currently looking for an oscilloscope, but I don't know much about these things. Maybe someone here could give me some advice. I found this oscilloscope on EBay. Is it a good deal?

Which brands/models should I look for? And which accessories do I need? (Except manual/probe)

 

[tangent]

Oscilloscopes from eBay are overpriced. It's a seller's market. It's not quite as bad as buying them from one of the big refurbishers, but on the other hand you don't get the guarantees that you get from a big used equipment dealer.

Instead, try to find one locally. Ham fests are said to be excellent sources. If you know other electronics people, ask them; they may have a line on an old scope that's being given away or sold because it's too slow for current projects at their company. For audio, almost anything will work.

Tektronix and HP/Agilent are your best bets. Not only do they make really good equipment, it's well understood so if it ever breaks you can find the information out there to fix it. The best bet for fixing old scopes are the very old ones, because they used mostly common parts. From the late 70's onward, they started using a lot of custom ICs which are no longer in production, so to fix one of those you have to cannibalize a second scope. Try not to go so far back in time that you get into tubes.

Late 60's to mid 70's is your best bet. The Tek 465 line is a wonderful bet.

 

[BradJudy]

I picked up a Tek 2430A (I noticed that same peron is selling one for $1000 on eBay) cheap at a surplus auction. Unfortunately it died right away

. I don't know enough to repair it, but I'm hoping to get a friend to take a look sometime.

Tangent: You ever head over to Los Alamos and stop by The Blackhole? You should if you haven't - I think you'd dig the place (tons of surplus stuff from the labs).

 

[tangent]

LANL is 4 hours from my house. Too far to go for a scope.

 

[Jupiter]

Thanks for the advice.

I don't know any EE industry people, but I'll check out any ham fests if I hear of any.

I forgot to mention that I'll be building digital equipment at some point.

I looked around and found these:
- (several) Tek 465, no probe/manual: ~200 on EBay
- Tek 475 (200 MHz), incl. probes/manual: $200+shipping
- Tek 2445 (150 MHz), incl. probes, 30 day warranty: $425
- Tek 2465 (300 MHz), incl. probes, 30 day warranty: $525

I assume I'll have a problem getting the 2445/2465 fixed cheap. But any good deals here? The 475 maybe?

 

[kevin gilmore]

The 465's and 475's (and 485's) are all getting so old they
need electrolytics in the power supply (about 10 of them, various
hard to find sizes) and the rotary switches are dirty, and
probably intermittent. Some of the front end ic's are no longer
available either, so if a channel is blown, its over.

The 24xx series is a much better idea. Some of these are
more computerized than others, there are much less rotary
switches, most are electronic. The 2467 is highly desired.
These have switchers as the power supply, and are a real
pain to fix when the switcher smokes. A 2465B is a great
all round scope.

Stay away from 7000 series mainframe scopes, these have
problems with the high voltage trippler, and if this goes you
will not be able to get it fixed.

 

[jeffreyj]

Quote:

Originally posted by Jupiter I'm currently looking for an oscilloscope, but I don't know much about these things. Maybe someone here could give me some advice. I found this oscilloscope on EBay. Is it a good deal? Which brands/models should I look for? And which accessories do I need? (Except manual/probe)

Buy this scope immediately.

No, really. It's a fantastic deal. My Tektronix THS720A - a portable 100MHz dual channel DSO - cost me approx. $4,000 brand new several years ago. To get any working 100MHz+ BW Tek scope used for less than $500 is a steal.

You got your measurement cursors on this one, 4 channels, 150MHz of true bw, and no, I'm not the seller (I wouldn't part for it for so low a price, even if I had a bad crack habit to support.)

 

[jamont]

Or how about this one:

http://cgi.ebay.com/ws/eBayISAPI.dll...gory=4677&rd=1

kevin's caveat notwithstanding, this looks like a good deal to me.

 

[Jupiter]

Quote:

Originally posted by Jupiter I'm currently looking for an oscilloscope, but I don't know much about these things. Maybe someone here could give me some advice. I found this oscilloscope on EBay. Is it a good deal?

I emailed the seller and he said there are no probes included. Anyone know how much I have to pay for those?

The Tek 475 is no longer an option (sold). I've emailed the seller of the Tek 2445/2465, but I haven't heard back from him yet.

And thanks for the help, everyone.

 

[Jupiter]

Quote:

Originally posted by jamont Or how about this one: http://cgi.ebay.com/ws/eBayISAPI.dll...gory=4677&rd=1 kevin's caveat notwithstanding, this looks like a good deal to me.

Definitely cheap, but it doesn't look like there are any probes included. The seller also has a low rating, so it sounds like a risky deal.

 

[jamont]

Probes tend to evaporate apparently. Most of the scopes offered on ebay don't have probes. It's certainly a plus if it does, as they are expensive - $50 or so for a passive Tek probe is very common on ebay.

 

[kevin gilmore]

I have a 7603 i use with the spectrum analyzer plug in.
As pictured the unit has the timebase in the left slot.
I just tried it. The scope cannot work with the timebase
in the left slot. The timebase has to be in the right slot...
I worry about something when the picture and text
are obviously wrong.

Still the price is very cheap. The 7603 frame is only
good to about 100mhz regardless of the plugin's.

 

[jamont]

Yeah, now that you mention it I never recall seeing the time base in the left slot

thanks kevin

 

[braillediver]

How much bandwidth do you need in a scope to work on audio gear?


Mitch

 

[jamont]

Quote:

Originally posted by braillediver How much bandwidth do you need in a scope to work on audio gear?

Not that much. Tektronix used to say 5x the highest frequency of interest, so for audio say 5x 0.1 MHz = 0.5 MHz. It's hard to find a scope thats less than 10 MHz, but the faster ones have all the cool features...