All my silly-scopes back to the gas-fired EICO 427 would read 50kHz.
(* Whoops. The 1937 Allen B DuMont I found at the curb gutted and re-built with Tandy bits barely made 19kHz.)
Accuracy may be an issue. No longer a 100kHz SWL calibrator on every block. Scaling-up from power line subjects you to capacitor ratios which could be as bad as +/-20% (tho I think even the 427 used 10% parts here).
Thanks! Yeah, locally I can see a couple of 1102e for $400, Hantek appears to be another brand that has some presence locally. Sounds a bit more expensive, not sure if it is better, comparable or worse than Rigol.
Would the Rigol 1xxx serve as distortion analyzers for such scenarios where you need to place the harmonics "correctly", or does that require a completely different product? (sorry, completely clueless as to the extend of functionalities of the oscilloscopes... the manual for the Rigol does list FFT charts, but not sure if that is enough or you need a dedicated distortion analyzer that can filter by harmonic).
Still, it looks like $400 is a bit north of what I would consider a "budget" purchase for the rare occasion a non-pro needs an oscilloscope. Thanks anyhow.
Rafa.
There's no trimmer to be adjusted and no scope needed, for the Nelson Pass front end card with Toshiba JFETs. Same goes for Scourge and Bulwark. If someone figures out a way to port "M2x Cedarburg" over to this amp, that also has no trimmer and needs no scope. The scopeless are not entirely hopeless.
Sounds like fun! I bought a $19 oscilloscope link, played with it for a day, and threw it away. Hope you have better success.
Remember that some people will accidentally overshoot the target and will need to display 100 kHz square waves while they furiously dial the knob in each direction, looking for a way to reduce the frequency.
Remember that some people will accidentally overshoot the target and will need to display 100 kHz square waves while they furiously dial the knob in each direction, looking for a way to reduce the frequency.
I meant for "other" amps, like the F6 if I remember correctly?. My question was more: will this be something that can fill multi-purposes or is it a one trick pony, for us that don't delve in electronics all day long!
I feel I am perhaps miss presenting my point: this is an expensive tool. For a professional, a must, no questions asked. For a hobbyist, things are less clear. If I am aiming at a $500 Kit, spending $400 for a tool to measure one of 5 input stages, seems overkill. Would that serve as a distortion analyzer for a future build, then maybe the price can be justified, were it also dubbing as a better multimeter than the $40 I have, better... would it have a 50W soldering iron attached to it, yes, then $400 is now looking like a reasonable expense.
I know they don't do all that, I'm trying to make my point, but I find it more often than not, I am taken to the last ounce of possible error in my wordings, instead of some leniency into what I am trying to ask.
Do I understand there is no need to measure the phase of the second harmonic on this input stages, yes. Do I understand that the VFET KIT will even come party pre-assembled and it is a single pot one needs adjusting, yes. I am asking about the broader use of this expensive tool.
Seems like an interesting topic, as there are some answers, some by heavy, heavy weights here!, and PMs coming my way with info (thanks!). I know it's off topic nonetheless to the thread.
Sigh.
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Thanks for the info! Would that be one of those USB only ones? Would you recommend those for a starting point? Looking forward to your findings!
Thanks!
Yes Mark, I think a $19.00 oscilloscope would be just that - to play with. It will be interesting to see what Wayne reports with regards to his $30.00 purchase.
With oscilloscopes these days - you get what you pay for, back in the good old days, facilities would have purchased a CRO from either Tektronix or HP - both made in the USA with quality in mind - the older vacuum tube designs were built like battle ships and many are still functional. Now, so many are made in China, one needs to be more careful to get hold of a decent digital oscillosope these days - it pays to do a bit of homework and research.
With oscilloscopes these days - you get what you pay for, back in the good old days, facilities would have purchased a CRO from either Tektronix or HP - both made in the USA with quality in mind - the older vacuum tube designs were built like battle ships and many are still functional. Now, so many are made in China, one needs to be more careful to get hold of a decent digital oscillosope these days - it pays to do a bit of homework and research.
Mark,
Very cool and thank you for your hard work!
The bridge rectifier input makes the build very easy for many people. Those of us that cook up our own PSU may not like this, but clearly you and Nelson want these amps actually built!
I’m going to give away some Tokin devices to the right person that can prove that they have already built everything or at least have everything except the devices.
Cheers,
Greg
Very cool and thank you for your hard work!
The bridge rectifier input makes the build very easy for many people. Those of us that cook up our own PSU may not like this, but clearly you and Nelson want these amps actually built!
I’m going to give away some Tokin devices to the right person that can prove that they have already built everything or at least have everything except the devices.
Cheers,
Greg
I'll vouch for LCSC. They are a sub-company of JLCPCB. I've ordered hundreds if not thousands of parts including, IRFP mosfets, LM3886, zener diodes, BC5XX, Toshiba TTC5200, etc. So far so good. No fakes that I can see when inspected visually or installed in a circuit. Their prices plus shipping will still usually beat any other source. Gravy.
Darn, I think Mark just let out a really great secret.
There are a couple of guys in Nelson Pass's VFET thread who are gabbing about how easy it would to make a balanced input for this amp, both the circuits and the chassis mechanical modifications. However I don't think it's anything more than idle chitchat at this point. Go over there and see for yourself. Maybe you can join their team and inspire them to get started on the idea for real.
It might be early to ask this question since no winners have been decided yet, but of the 4 stages is there a "best"? What type of sound is typically associated with the topology of each board; aka, what will these stages roughly sound like?
If conversation about the stages is the burden of the owners of the amp, the topic of component matching and engineering synergy would be useful. Will one stage be better suited for a high impedance tube preamp? Will one definitely get along better with solid state?
If conversation about the stages is the burden of the owners of the amp, the topic of component matching and engineering synergy would be useful. Will one stage be better suited for a high impedance tube preamp? Will one definitely get along better with solid state?
