Oscilloscopes

Discussions about Sinclair ZX80 and ZX81 Hardware
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SabreWulf
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Joined: Mon Jul 26, 2021 6:31 pm

Oscilloscopes

Post by SabreWulf »

I'd like to acquire an oscilloscope for ZX81 and Spectrum repairs, also for generally understanding what's going on in them, and for other projects. I used oscilloscopes regularly in a former life, but that was so long ago that I might as well have imagined it. The budget isn't limitless as this wasn't even supposed to be a hobby, but what do I need, what should I expect to spend and where should I look for it? Are there used models that are solidly good buys? Are there new models that make more sense nowadays in respect of price, technology, reliability and features? I have little idea and there's a lot out there. Any help would be much appreciated.
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1024MAK
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Re: Oscilloscopes

Post by 1024MAK »

The Rigol DS1054Z 50MHz Digital Oscilloscope (one supplier here, this was just the first that came up in a search) is a popular four channel type.

Stewart of Reading is another good place to look.

Traditional CRT ‘scopes can also be used. Although digital storage types are far more flexible, as digital signals in computers are not nice repetitive waveforms.

The analogue bandwidth needs to be at least 25MHz, but if you can, go for 40MHz or higher.

Also have a look at these topics over on StarDot forums link and link.

Mark
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SabreWulf
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Re: Oscilloscopes

Post by SabreWulf »

Thanks for the swift reply Mark. The Rigol sounds like it would be ideal.
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mrtinb
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Re: Oscilloscopes

Post by mrtinb »

I bought a Hantek 2C72 for $130. It has 70 MHz. My first oscilloscope.
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Neurogate
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Joined: Tue Aug 31, 2021 6:46 pm

Re: Oscilloscopes

Post by Neurogate »

For repairing old computers, as a hobby, I use really simple oscilloscope Fnirsi - 2031H with price less than $50. Yes, it's look as baby's toy, but for old hardware with low frequencies it's can be useful.
Sinclair ZX81, Sinclair QL, Sinclair ZX Spectrum +2, Atari 130XE, Commodore 64C, Commodore C128, Yamaha YIS503IIIR MSX2 & etc
AdrianPilko
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Re: Oscilloscopes

Post by AdrianPilko »

I recently got a Hantek DSO5102P from amazon and already used it to help repair a Speccy which wouldn't load from tape and debug a zx81 composite mod. I'm fairly new to using a scope but is easy to setup and works really well. I wouldn't be without it now and can't wait to get another "for spares" or "untested" bargain from ebay.
DrVenkman
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Joined: Mon Jul 05, 2021 3:44 am

Re: Oscilloscopes

Post by DrVenkman »

I have a Siglent SDS 1202X-E two-channel 200Mhz scope and it has been ideal for diagnosing and repairing my Atari, Commodore and now Sinclair machines. After using it regularly for over 2-1/2 years, I have zero complaints.
bola_dor
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Re: Oscilloscopes

Post by bola_dor »

I bought a Hantek 2C42 hanheld oscilloscope/multimeter. It's on the cheap side, had to buy a 2nd probe separately.
Has two channels, rated 20Mhz but served well to see 14mhz at spectrum crystal and 6.5Mhz at zeddy oscillator.
Has only two channels and some times I wish it Has mor to see some logics working.
The screen it tiny and you can't manage much the scales so for example if using 1v scale it tops about 7 or 9v and will miss a 12v rail. Can be connected to a computer but I don't use to..
Ernesto
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