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Products => Test Equipment => Topic started by: Noidzoid on December 04, 2019, 03:03:39 pm

Title: Insanity or cheap dso?
Post by: Noidzoid on December 04, 2019, 03:03:39 pm
Not having much luck with my Hameg HM-605 repair project so far and I'm spending far too much time on it.  I would like to think it will be fixed sometime, but for now I could do with an oscilloscope that works.......as in now.

The time I have already spent on trying to fix this scope I was hoping to have used learning how to fix CD players.  Although I have enjoyed my time with the Hameg having learned a few things along the way I feel it's time to put it on the to do shelf.

Funds are low and rather than buying another used scope (that may/may not need fixing) I am considering a new Owon SDS1102 (yes funds are low). Three reasons being the cost <£170, Peter Scargills review on YouTube and the fact it is new and should just work out of the box.

My question to the learned folk here is, is this scope suitable for working on CD players and maybe other audio equipment and maybe a few early playstations.

One thing I know I do need from the new one is X/Y mode. When I was looking at old analogue scopes it was easy to see on the faceplate if this was available, (the scope I acquired before didn't have this, so didn't really get used hence the Hameg purchase).

Also thanks to everyone who helped with the 605.
Title: Re: Insanity or cheap dso?
Post by: james_s on December 04, 2019, 04:45:47 pm
If you need XY mode then you need an analog scope. I've yet to use a DSO that has a decent XY mode, even quite high end stuff. For testing vector game boards it is completely unusable, one of the main reasons I keep my old Tek 465B around.
Title: Re: Insanity or cheap dso?
Post by: maginnovision on December 04, 2019, 04:56:02 pm
Fun images, lissajous patterns, and lower framerate vector games work fine on the R&S RTB in my experience. I doubt something like doom would work well, but I haven't seen that look good on an analog scope either. Out of his price range but it works fine. The key with DSO's doing XY is one it has to be implemented properly, and two you need to properly adjust settings but primarily the time/div and memory depth settings.
Title: Re: Insanity or cheap dso?
Post by: Noidzoid on December 04, 2019, 07:19:13 pm
I may have made a mistake regarding the need for X-Y mode.  I was sure I read in the CD players service manual that this function was to be used when testing. After having another breeze through it I can't see reference to it.  I even bought the HM-605 because of it!
Have I been really stupid? (Though I assume the component tester that I repaired on the Hameg with the kind help of forum members uses X-Y mode?)
Is it normal to need X-Y mode in CD player repair or have I lead myself astray?
Title: Re: Insanity or cheap dso?
Post by: shakalnokturn on December 04, 2019, 07:29:04 pm
Usually one of the early checks in sequence on CD players is the "eye pattern" or RF, it does look a bit of a mess on an analog scope. Are you confusing that with X-Y?
I've never used X-Y on a CD player, can also confirm X-Y is quite useless on a DSO.
Title: Re: Insanity or cheap dso?
Post by: Noidzoid on December 04, 2019, 08:02:14 pm
Usually one of the early checks in sequence on CD players is the "eye pattern" or RF, it does look a bit of a mess on an analog scope. Are you confusing that with X-Y?
I've never used X-Y on a CD player, can also confirm X-Y is quite useless on a DSO.

That sounds like what I have done, though I can't think why.

I must have been reading about something else, though I can't remember what.  I can't believe I've been chasing something I don't need for so long!!!!!

Either way, could I ask for opinions regarding my opening post in this thread (obviously disregarding the X-Y statement).

Thanks for your patience.
Title: Re: Insanity or cheap dso?
Post by: Noidzoid on December 04, 2019, 09:16:36 pm
I suppose I should be happy as (please correct me if my assumption is incorrect) I don't need a DSO, X-Y mode or even (for looking at the eye pattern) more than one working channel for typical cd player diagnostics........ I can still use my analogue,1 channel, 605 for something.