As I've moved up to using ~10Mhz I've found that my OWON PDS022S 25MHz scope is not enough. As such, I've just placed an order for a new Rigol DS1102E 100MHz scope . I would have gone for higher, but I just cannot afford it. As it is that smell of burning plastic is my credit card .
http://www.rigol-uk.co.uk/Rigol-DS1102E ... PwLXeFedTt
Can't wait until next week when I can have a play!

54 pounds of VAT? Ouch!

The specs look good. A 10 MHz square wave should look pretty rectangular on this unit. What about probes?

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

I've got my Owon ones for now, but will have to save up for 100MHz rated ones if they don't come with the scope (which it doesn't look like they do, sad to say). Once I've done that, I think it'll be time to get a decent bench power supply. That'll be sometime during in 2030! And there was me thinking that this hobby is cheap to run .

These should do as they're rated up to 150MHz and you get a pair for the price:
http://www.rigol-uk.co.uk/Rigol-RP2200- ... Pz7_uERQYo

For a lot of things, you could get away with an $8 unregulated linear wall-wart power supply and put a $0.39 7805 linear regulator IC on your board.

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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

And that's $8 if you buy new, surely? Try to find an electronics / ham-radio flea-market / car-boot-sale that you can get to. A lot of interesting equipment passes through those, some of it in better shape or for better price than others. I think that my 200 MHz analog scope (four channels, one of which seems to have been disabled for some reason) ran me less than the VAT on that Rigol scope. And I probably overpaid.

On the other hand, you can also end up with some junk purchases from such events. I have a couple things that I haven't been able to find manuals for or get a useful behavior out of. YMMV.

As Garth noted, you can manage fine with a homebrew power supply using inexpensive parts. Or, you could do what I do and that is use an old PC power supply. You just have to be careful with one of those, as even a small one can produce copious amperage. An inadvertent design error or short in your unit could result in some serious smoke if the current draw doesn't exceed the power supply's limits.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

Would using fuses or circuit breakers at a far lower limit than the supply uses internally help at all here?

A circuit breaker is much too slow to be of any help, but a fast-acting fuse might mitigate the damage. However, "fast-acting" is relative to the time it takes for many amps to turn a circuit into a smoke machine. Even a few milliseconds might be all it takes if the fault is significant. With a 7805 regulated circuit, the current limit is a hair over one amp and the regulator will basically take itself off-line if connected into a direct short or a substantial overload.

What I do on a new unit to reduce the likelihood of smoking up the place is to first meter Vcc to ground to detect any egregious faults. Then I apply Vcc through resistance to act as a current limiter. If things seem to be copacetic then I apply Vcc directly. So far I haven't lost one to a major fault.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

Speaking of things going up in smoke: One thing I've found (to my cost) is that you can connect an LM7805 reversed. I.e. Connect the input voltage to the output and outpout to input. If you do this then I think it just transmits the entire voltage through (rather than stopping or regulating it).
I accidentally did this after creating a small 7805 module for a 9V battery and foolishly didn't mark the inputs and outputs. Fried a W65C02S. Meh . The 7805 was ok though. lol.

Sometimes smoke is your teacher. For example, one time long ago I assumed the pinout on a 7905 (negative voltage regulator) is the same as the pinout on a 7805 positive voltage regulator.

It isn't.

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In 1988 my 65C02 got six new registers and 44 new full-speed instructions!
https://laughtonelectronics.com/Arcana/ ... mmary.html

Is that where you use your olfactory senses to troubleshoot the circuit?

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

That's the way it always works. The cheap part survives and the expensive one blows up.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

Bad news. It seems the model that was after (at a low price) isn't coming into stock until the end of April. So I've cancelled it. Rats.
I'll have another look around to see what's available. I just don't want to buy one from eBay as I'm not sure what I'll get (knock off pretend version, etc.).

Hmmm this might do the trick:
http://www.amazon.co.uk/SDS7102V-100MHz ... won+100mhz
What do you guys think?