What is on the top of this scope?

[Andy1845c]

**broken link removed**

Is it somthing like a DMM? I see volts and time, but I can't make out the rest of the buttons. I see a few scopes have features like this, an some newer ones have readouts on the screen. Are these features of any use to a novice like me when looking for one to buy?

 

[agent420]

Looks like a Tek Dm44 dmm option...

Not a bad price for a 465B, just be careful with untested test equipment (actually, that's kind of funny )... 'Powers On' could mean only the power light comes on... Note the seller's return policy does not apply as they advertise it 'as-is'... But it does appear to be running in the photo...

 

[jpanhalt]

It's unclear how experienced the OP is with electronic items on that auction site. Agent420 has it completely right. "Powers on" may likely mean that the power on light comes on. Traces on the screen don't mean the acquisition and attenuation functions work. For myself, I am very cautious of sellers with less than a 99.5% rating, particularly when they have thousands of feedbacks. Look at some of the comments, including the "ok" ones. Good luck. John

 

[Andy1845c]

Thanks for the replys. I'm not really looking to buy this exact scope, but more wondering what that feature is all about. I am very leery of scopes on ebay. Pretty much the reason I don't have one yet.

 

[j.p.bill]

$200 for a working 100 Mhz dual-trace scope with the DMM (you get a temperature readout, too) is just on the verge of too-good-to-be-true. On the other hand, that design is 37 years old.

If it works, it would be a good piece of test equipment. Very good for audio work.

 

[Sceadwian]

Even if it only worked for a year or two, it'd be a good deal. You shouldn't be leery of e-bay, you should just do your research. Examine a buyers feedback in detail.

 

[Andy1845c]

I'm sure I will end up buying one off ebay, unless I find a better source. But I have been looking for one in my price range that the seller seems to know a little about and says will pass basic tests and guarantees not to be DOA. So many Ebay scope seem a little fishy. Powers on means nothing to me. Seems like a deceptive way of saying "don't think it works". Many scopes are flat out described as parts/repair units. I don't know enough to try and fix one. I also worry about shipping it too. I bought my ham radio off ebay, and while it was packed well, a tube fell out and broke inside the thing. Seems like a scope would be fragile as well. Has anyone here got their scop off ebay?

 

[dav es tech]

I have bought a couple of scopes on ebay,
they worked as advertised.
Decent vendors typically supply a picture of the screen showing a trace when the calibrate osc is connected to the input.
Read all the feedback, less scrupulous vendors will play dumb
to avoid doing any tests.
Old HP and Tek were built like tanks and hold up well.

 

[Sceadwian]

I bought a 500khz scope (powers on sold as is) for 15 dollars, shipping 15 dollars. Both channels work fine (down to 100 microvolts) one channel is a little noisier than the other. Timebase is good, triggering is very sketchy but it has an external trigger which works fine. A good internal cleaning of the pots would probably make it as good as new. For 30 dollars it's the best purchase I've made so far.

 

[Sceadwian]

Mines an old HP 1200B. They really are built like a tank. Full sized rack mount, solid metal handles (aluminum). For the 30 bucks I paid even if it didn't work it'd be worth it for the materials in it alone, let alone anything that was still functional.

 

[Andy1845c]

I bought a 500khz scope (powers on sold as is) for 15 dollars, shipping 15 dollars. Both channels work fine (down to sub milivolts) one channel is a little noisier than the other. Timebase is good, triggering is very sketchy but it has an external trigger which works fine. A good internal cleaning of the pots would probably make it as good as new. For 30 dollars it's the best purchase I've made so far.

Thats awesome

Have you ever repaired one? Are there certin components in them that are common to fail?

 

[Sceadwian]

Oh no, definitly not =) If mine died on me, I'd check the fuses, check the power supply, look for black marks somewhere near the power or signal input lines, caps and maybe test a few random components. But if something like the tube goes, you could buy a new scope for the cost of a replacement tube, if you could even find one. If I could find the right buyer I could probably get twice the price I paid for the entire unit for any single component in it =)

 

[j.p.bill]

Most failures I've seen in Tek scopes were in the high voltage section. They like to use quadruplers, and tend to lose the occasional diode. They are high voltage types, and do not check with just a few volts applied. Not too big a deal to replace, though.

We had a 475 that turned into a turkey, though, because the switches in the second vertival channel did not make reliable contact. They were little gold leaves, and hinged down to make contact. They never were reliable, even after sending the scope in for cal/repair.

I've got a Tek 2221A now. It's only 100 MHz, so it's pretty weenie for logic work. I do mostly analog work, so it's great. Dual analog channels and digital storage. Couldn't be better.