This a good beginner 'scope?

[sansbury]

http://boston.craigslist.org/sob/ele/307672005.html

Leader LBO-511: one channel, no probes, $25, said to be in working condition. Looks like a 100Khz bandwidth? As you can see my knowledge is limited. It'd involve a nice 2-3 hour drive from Boston to Cape Cod and back so I don't want to bother unless it's usable for more than a $25 doorstop.

I am mostly interested in amp/preamp work at this point and not so much the digital stuff. I realize that I could get more for $100, $200, $400 etc. but if I can get an OK scope for the price of two martinis and save the rest for parts to build more stuff to test I'd rather do that.

 

[RetroAudio]

it's not $25 with the gas money and time involved. don't be cheap when it comes to a scope but there's nothing wrong with a good deal either. and maybe consider a 2 channel scope at least, although 1 will still be good for a lot.

 

[SY]

Don't cheap on important tools. Two channel, triggered and delayed sweep, at least 40MHz (100 is better), top tier maker. Yes, that will be closer to $150-250 than to $25, but you wouldn't work on your car with Bob The Builder plastic wrenches, would you?

 

[sansbury]

OK then, guy just told me he has someone driving down from even farther away than me (Cow Hampshire! 3 hours easy) to pick it up. But he also has this rig to sell for $200:

http://boston.craigslist.org/sob/ele/307634085.html

My concern is this thing would be serious overkill for a newb like me, and perhaps that if one part of it breaks, the whole thing is shot and I'm out $200.

-- Agilent / Hewlett Packard / 16500A Logic analyzer mainframe:
Consisting of 2 built-in 3.5 inch floppy disk drive, built-in RS-232 and GP-IB interfaces, Color touch screen.

-- (One) 16530A Timebase plug-in card:
This card is designed for use with the 16531A oscilloscope card and provides an Oscilloscope-on-a-Card capability.

-- (Two) 16531A 400MSa/S Oscilloscope cards:
This card is designed for use with the 16530A timebase card and provide an Oscilloscope-on-a-Card capability. Bandwidth of 100 MHz and sample rate of 400 MSa/s. Has 2 channels per card (for a total of 4 channels with 2 cards).

-- (Three) 10433A Probes

-- System Driver Disks

-- HP Thinkjet 2225A with GP-IB cable

 

[SY]

For $200, stick to a good quality analog scope with a name like "Tektronix" on it. It will be the best money you've ever spent on this hobby.

 

[kscharf]

This is NOT a good scope for digital work. It would be fine for audio work. In it's day it was considered a tv scope, but would not be useful for today's digital HDTV etc.

You know, you can pick up an older used Tek on ebay for $100 or so.
I have an old Tek 453 scope that is STILL useful for digital work that I got for about $200-$300 years ago.

 

[nuvistor]

Tek 2215 show up on eBay regularly for < $100, 60MHz with delayed trigger, a budget analog scope from the early 80s, works fine for me.

HP 1220/1222 may be available for less, 15MHz, calibrated sweep but no delayed trigger. OK for audio frequency but may miss HF parasitic oscillation problems.

The Leader is certainly better than no scope at all.

 

[sansbury]

Well, the cheapo Leader was gone before I got to it so that choice is moot.

I live in Boston and see the next MIT flea market is this coming Sunday so I think I am going to hit that first, have to imagine there will be at least a few things to see there in or near my price range. Besides, part of the reason I love living in Boston is being able to say, "I'm going to the MIT flea market this weekend to look for an oscilloscope."

In case anyone is looking for it: http://www.mitflea.com/

I hate the idea of paying $40 for a scope on eBay and then paying $50 to ship it.

 

[EC8010]

I hate the idea of paying $40 for a scope on eBay and then paying $50 to ship it.

Well, there you have it, why waste money shipping a cheapo. Go for an analogue 'scope with "Tektronix" written on it. At least 60MHz, and preferably 100MHz. Definitely two channels, and it's nice to have delayed timebase (but not essential). As SY says, saving money on an oscilloscope is wasted money. Think about it; you're going to make measurements, and on the basis of those measurements you'll spend some money or rebuild something you already spent money on. Now, how much would it cost if your test equipment made you make the wrong choices?

I use a Tek 2213 60MHz analogue 'scope and a Tek TDS3032 300MHz digital 'scope. Stay away from digital 'scopes until you know far more.

 

[rcavictim]

but you wouldn't work on your car with Bob The Builder plastic wrenches, would you?

Sy,

I think that is what many allegedly professional auto repair shops here in Ontario must use based on the cost and quality of the repairs we see. Aren`t Snap Off wrenches, a competing brand, also all made of plastic?



I agree that it is a worthwile investment to get a high quality, all analog two channel o-scope with delayed TB and 100 MHz BW. They are not expensive bought surplus. The idea of a radio parts fleamarket held at MIT sounds like a lot of fun! We Canadians get nothing like that up here. Our military electronics surplus doesn`t get written off by the government until it is at least 100 years old and then it comes with ALL the capacitors removed making it worthless junk because they put totally untrained doofuses in charge of making the stuff PCB free. Guys that wouldn`t know it if a real PC Bee bit them in the a$$.

 

[Conrad Hoffman]

Get a late model Tek scope, two channels, 100 Mhz, guaranteed working. Watch out for the earlier solid state models like the 465B. They're nice to work with when they work, but are old enough to be unreliable, and are difficult to service. Though I have one of those, I actually still use a "boat anchor" Tek 545B that uses tubes and is only 40 Mhz. You don't want one of those unless you know how to service it, have spare tubes, and need extra heat in the winter. On the upside, they practically give them away at hamfests- around here they often get left behind for the dumpster. On the further upside, with a 1A7A plug-in, I can make measurements down to microvolts per centimeter, albeit only to 1 Mhz. Very useful for sorting out ground and noise issues. The long tubes can also be focused much more sharply than the later better protected scopes. I recommend against the low end HP scopes (dim fuzzy traces), and Phillips scopes (unless you can get docs), and any of the non-name brands. Leader actually made some decent scopes, but parts are often needed, and impossible to get. I've used several Leaders and didn't dislike them, but stick with Tek. Digital scopes do some things very well, but aren't well suited to audio. I'd only pick up a digital scope if I already had an analog scope to fall back on. OTOH, for mostly digital and high level analog work at work, I wouldn't use anything else- they can help your productivity and documentation tremendously.

 

[I_Forgot]

-- Agilent / Hewlett Packard / 16500A Logic analyzer mainframe:
Consisting of 2 built-in 3.5 inch floppy disk drive, built-in RS-232 and GP-IB interfaces, Color touch screen.

I would avoid this like a case of multi-drug resistant TB. I had some logic analyzers back when I used to deal in surplus electronic stuff and found that even a working logic analyzer is junk if you don't have a complete set of probes for it, and that is how they normally end up on the surplus market- missing probes. A set of probes will cost you a couple thousand dollars if you can find them.

Logic analyzer development and obsolescense are similar to that of PCs. They should be cheap, but since the probes and the analyzers are normally stored in two different cases, they are normally not found together on the surplus market. If you want to make some money, start hunting and reselling logic analyzer probes. There are a million surplus boxes out there that need probes to become functional.

I_F

 

[OzMikeH]

Once CROS get over about 15 years old you not only need to know how to use them, but how to repair them. switches get grotty, capacitors dry out. all sorts of issues. stay well away from anything made by Velleman too.

Getting one with a CRT is cheaper but bulkier so it will cost you a LOT more in freight, some digitals are only 2 inches thick.

dual channel is very useful for fault finding, I use two probes, one connected to the test signal source and fiddle the cal so I can exactly overlay the two traces to look for distortion. (this is where a nice sharp focus is important.

20MHz at least, 40Mhz better (go for a quality 20Mhz before a cheap 40MHz)
Good brand: Philips, tektronix, HP, have a look inside if you get a chance, the circuit board materials, screen printing etc will give you a good idea of quality.

my next project is restoring this old beast.
a 30kHz single channel Philips CRO. That's right, kilohertz... next to useless but how quaint!

 

[OzMikeH]

If you see anything like this avoid it, a great bit of gear if it's working correctly but it has 2 handles for a reason - they are extremely heavy. There are about 30 tubes in these, they only last for so long too.
that screen is about 5 or 6 inches across.

Looks like a great buy but you need a real smart old-timer tube freak to fix it. - any volunteers??

 

[EC8010]

Quaint indeed.

One other possibility (if you're offered one for free, and no postage) is a 20MHz dual channel Gould. They used to be very popular in university labs and they're almost bomb proof (they need to be, when dealing with students). The great advantage of these Goulds is that they use almost entirely discrete components so they're maintainable almost indefinitely. I'd concur with the advice to stay away from Tek 465 etc; you want the final generation analogue Teks.

 

[EC8010]

Looks like a great buy but you need a real smart old-timer tube freak to fix it. - any volunteers??

Let's see, postage to UK and back...

I once bought a 555 for £10. Two handles for the oscilloscope, plus separate power supply (only one handle). Excellent source of useful bits.

 

[rcavictim]

If you see anything like this avoid it, a great bit of gear if it's working correctly but it has 2 handles for a reason - they are extremely heavy. There are about 30 tubes in these, they only last for so long too.
that screen is about 5 or 6 inches across.

Looks like a great buy but you need a real smart old-timer tube freak to fix it. - any volunteers??

I had three of those fresh from government surplus a couple of decades back and I referred to them as a 500 watt fan forced space heater with an o-scope screen to monitor their performance.


I wish I still had them today as a source for tube amp parts!

 

[rcavictim]

Quaint indeed.

One other possibility (if you're offered one for free, and no postage) is a 20MHz dual channel Gould. They used to be very popular in university labs and they're almost bomb proof (they need to be, when dealing with students). The great advantage of these Goulds is that they use almost entirely discrete components so they're maintainable almost indefinitely. I'd concur with the advice to stay away from Tek 465 etc; you want the final generation analogue Teks.

EC,

I have one of those Gould`s, a dual channel unit with a pretty much permanent position on my audio bench and that is what I primarily use there. Great scope for this purpose. I paid about $60 for mine a decade ago and have had no problems with it. Good suggestion!

For more demanding measurements associated with RF or fast stuff
I have a 120 MHz Delay timebase dual trace Philips (since almost new) that travels to where I need it on the property only. It has developed a flaky delay line which I fixed with a rubber elastic band instead of a $1000 repair. I agree with the other poster not to get a Philips. I also shuffle around here most often with my Tektronix 1740A dual trace delayed timebase (100 MHz?). I bought two of those for $40 each at the Rochester Hamfest and made one good one from both. I have a spare CRT and everything else for it as a result. Nice scope but the triggering is poor. That may be an actual circuit fault and not a characteristic of the model. I do not expect to own a digital scope.

I have a Tek 564 dual channel storage scope that sits on the equipment shelf in the lab. I haven`t used it in many years since it served for a decade as part of a real time Hydrogen line spectral line microwave receiver display. I also have the same scope without storage. What was that one, the 562 or something? There is also this old HP scope that I bought because it had a good 141T storage mainframe to use in my microwave spectrum analyzer. That one gets fired up occasionally.

I found a mint 5 inch, `Precision` brand TV service man`s scope from the 1950`s at a hamfest for $5 and bought it because it looks great in my collection of 1940`s vintage TV receivers in my home. That one works but needs a recap. Beautiful black wrinkle steel cabinet finish and black face highlighted with aluminum raised etched printing and border. Pointy black knobs. I would have given my eye teeth for that scope when I was a kid and it was almost new! Much better than the cheap Eico`s and Heathkit scopes of the same era. It actually has two accelerator sections on the scope tube bell IIRC and the detail to shielding inside is very good for the era. I`ll bet it was expensive.

Then there is this old 1960`s, 3 inch Telequipment rack mount scope .......
Gee I have accumulated a lot of stuff.

 

[SY]

That old Tek is not only a fine parts source, it's a source for the best terminal strips on the planet Earth.

 

[Apex Jr]

The older 500 series scopes are great sources for tubes
and as Sy stated those terminal strips, CERAMIC.
THere also good for movie props for period films from the
60's and are rentable or saleable too.

I agree with the above statments on the Tek 465 scopes
but wouldn't dismiss the update version 465B's
These are great scopes and now priced right just make
sure you get one that has there dual display.

The MIT Flea market sounds like fun, to bad it's so far
for me...

Steve @ Apex Jr.