Do I need an Oscilloscope that costs $$$$$

[PRR]

{grumpy old man mode}
My first, an EICO 427, claimed 500KC (we didn't Hertz yet) but was awful bogus past 20KHz because the sync was a gas tube. Killed a lot of bugs with that.

Skipping ahead a little, I re-built a pre-WWII DuMont with a TL074 and a 555 and got 19KHz response, no pretense of calibration, and it was *great* for audio classroom use.

H-P made some spiffy 'scopes, but they had a very steady cash-cow in a 450kc job (120, 140, and kin), had a lot of uses.

All single-channel of course. A 2-input switcher would be a separate box.

Note that all of Television was developed mostly with 'scopes we would laugh at today. That "500kc EICO" was typical of late 1930s 'scopes (RCA did build a monster 5MC 'scope but I doubt more than a few were made for the vast development RCA was doing to break the Farnsworth patents).

I did have a 10MHz 2-input Leader. I liked to blow-up its probes so I rarely had two working inputs. My experience with chasing MHz oscillations is that putting a probe on a squealer damps the squeal, and probing a non-squealer sometimes caused it to squeal. I've never had lock-in on MHz parasitics, only a fuzzy hint.
{/grumpy old man mode}

_I_ think, if you have to ask, your *first* 'scope should be new and very inexpensive. This isn't rocket science any more. There's an open-source project for a 200KHz LCD 'scope, sold widely for $25-$120 depending on case and frills.

https://www.amazon.com/Longruner-Source-Digital-Oscilloscope-Assembled/dp/B07QN8XNLF
https://www.amazon.com/Quimat-Pocket-Size-Oscilloscope-Protective-Assembled/dp/B07QNJQJJ1
https://www.amazon.com/KKmoon-Portable-Digital-Oscilloscope-Interface/dp/B01DKGBJQY
https://www.amazon.com/Autek-DSO150-Oscilloscope-Pocket-sized-Digital/dp/B00C9U0HP2
https://www.amazon.com/Signstek-Portable-Handheld-Digital-Oscilloscope/dp/B00HEZKY28

This might also answer Merlin's wish for a "pedal 'scope" to poke ungrounded things.

[Prehistoricman]

I have a dual-channel 70MHz analog scope that does most of what I ask of it. It's even some use for digital type stuff. The lack of waveform memory can be a big deal depending on what you're doing and it's a limit on what you can do if you want to go beyond analogue effects.

But hey - I got mine for free so I shouldn't complain. If you go searching you should find cheap analog scopes.

[Invertiguy]

I'm just using a DSO138 kit off of Amazon. It's not exactly laboratory grade, but for my limited purposes (biasing BBDs) it's worked fine so far and hey, it was only $20. Plus it's small, runs on 9V, and fits nicely on my prototyping board. I might upgrade at some point but I'm not exactly in a position to drop hundreds on a piece of equipment I'll likely never use to it's full potential.

[Kevin Mitchell]

Though I've only used it a handful of times so far I really like using the SmartScope by LabNation. It even has a logic analyzer which was of great use for some of the things I get into. Their app is compatible with pretty much every OS - even smart phones. It's relatively inexpensive as far as portable oscilloscopes go. It's helped me calculate diode matrix scan timing for my keyboard (logic), tuning synth oscillators and biasing BBD stuff.

-KM