Hello again! (I'm still not electrocuted!) Meanwhile I'm reading and watching and learning a lot of stuff and I feel I'm getting into it more and more.
I have two more questions about workbench:
1. I have some spare cash, opportunity and will to buy used oscilloscope (it's my dream since physics experiments at school when I was 13 anyway) I don't think I need anything fancy, but I'd like it to be suitable for my tube amp project. They have a lot of parameters I have no idea how to interpret, but since tubes run at ~400V I thought input voltage is one of parameters to look at. OR am I wrong and ~400V input is not necessary? Anyway here are 3 models I'm currently considering (and are within my reach):
VOLTCRAFT VC 630-2 This one is almost like new ~160$
2 channels
300V input
more parameters:
http://www.conrad.com/ce/en/product/122 ... -to-30-MHzSCHLUMBERGER 5228 ~250$ - looks cool, has 3 channels but I'm confused about input voltages
3 channels
1 Mohm input 250V DC or 500V AC
50 ohm input 5V DC
more parameters in manual:
http://bee.mif.pg.gda.pl/ciasteczkowypo ... UAL%20(eng).pdf
HP 54600B - ~160$ Digital control and highest voltage input but I've read they are not good, difficult to use and not that accurate.
2 channels
500V input
Is any of them good? What would be Your advice? Any other suggestions up to ~300$? What parameters should I look at?
2. About safety devices. We are talking about two: isolation transformer for my safety and bulb dimmer for equipment safety. Diagram I posted above is some sort of hybrid of them and I agree about simplicity. BUT If I build these two devices separately - Can they be used together or do they mutually exclude?
If only one can be used, I'm obviously choosing isolation option, but If I can use both, is there any particular order they should be connected? Like: "wall socket - isolation - dimmer - amplifier" or the other way around?
Lastly, please look at these sites. Some local stores selling tube amp parts. What do You think of their offer? Can I stick to them as suppliers?
http://www.ogonowski.eu/transformers/power/ - amplifier dedicated transformers
http://sklep.lampyelektronowe.pl/?lampy-mocy,33 - no English version but symbols and company names should by obvious for You. Selling tubes, capacitors, transformers, knobs, sockets and a bunch of other stuff also amp dedicated.
Thanks in advance for any replies!