Bought a used SPECO ocilloscope - worth keeping?

[JoeG]

I was in a thrift store that happened to have a SPECO Model FS-4820 Oscilloscope for sale. The woman running the shop said "I have no idea what it is. But the price is $5." I told my wife about it during dinner out, and she said that I should buy it even though it has only a power cord, and I know zero about how to operate it. So for $5, I made a donation (in my opinion).


   


In searching the internet for information about it, I found out that it's identical to the AWS Model 620C oscilloscope. So I downloaded that manual for that brand and model.


   


Does anyone know if this unit is worth plugging and testing without any accessories such as probes?

Thank you!

Joe

[Garth Wilson]

I have that exact AWS 'scope, and it was a good one until it developed problems with the switches and they proved to be pretty much inaccessible to get contact-cleaner spray into them.  I also have another analog 'scope that's faster, but it has the same problem.  I had another nice, compact one that was great until the power supply went down, and everything was so tightly packed into this compact unit that I couldn't figure it out, and the manufacturer no longer supported it.  Then my employer gave me an Agilent digital 'scope that's far more capable, but I tell ya—that thing is not one bit user-friendly—it's user hostile!  I can't even get some basic displays from it.  It thinks it knows better what settings I want, and it won't just do what I tell it to.  (And yes, I've read the entire manual, twice.)  After I wrote about this on other forums, other people said that yeah, that's the way Agilent oscilloscopes are.  At my last place of work, I had a nice Philips DSO that was very easy to use.  It had an analog mode too, but I never had a need to use the analog mode.  I'm about ready to buy another new but old-fashioned analog 'scope before they're totally gone.  Even for digital work, I can nearly always get things to repeat well enough to see them on an analog 'scope.

Oh, one thing about oscilloscopes:  They're not much good without a good set of probes; and good probes are not cheap.  There's a lot more to them than meets the eye, and even the cable is not regular coax.

[Maximilian Hohmann]

Hello!

(06-25-2024 12:59 AM)Garth Wilson Wrote:  Oh, one thing about oscilloscopes:  They're not much good without a good set of probes; and good probes are not cheap.  There's a lot more to them than meets the eye, and even the cable is not regular coax.

Yes, of course. But just to test that oscilloscope I would suggest to buy the cheapest probe that can be found on eBay (I paid 1 Euro for my cheapest one, probably one percent of what it cost when new).

My analog scope is long gone, since many years a use a cheap(ish) Chinese clone of a digital Tektronix oscilloscope. Other than the mediocre LCD screen it is perfectly up to what I need it for. For me the two big advantages are the lack of a power cord - it is battery operated - and the UBS connection by which the data can be uploaded to a computer for further processing. If I ever buy another one it will be one of those small boxes that you connect via USB and run from your notebook.

Regards
Max

[JoeG]

It's starting to sound like this would be a good piece of older test gear that I can put on the the "FREE" table at the next VCF West in Orange, California (if there is one!).

Thank you for the replies!

Joe

[Ren]

I have 5 o-scopes, but I haven't used any in a while.
I think it would be quickly snapped up at the VCF, and you could probably get your $5 back!

Edit: If you are a "stereo" buff, you might want to keep it and have it display the waveforms of the audio signal you're listening to, just adding a bit of "bling" to your gear. At those frequencies, you can get by without probes, just some coax and BNC.