I recommend you build the thing and then consider snubbers once it works and you are happy with everything. It is a complex build.
Like 6L6s states in the PSU build guide, snubbers can easily be added from the bottom of the boards.
And yes, as 6L6 had to teach me too a few months ago, the circled terminal block shows the 120v wiring from IEC wires to dual primary transformer wires. The two black circular things are CL-60 NTCs providing inrush current limiting. The blue one is a line rated cap to filter high freq noise from the power lines/grid.
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I don't see C9 listed on the UPS v3 BOM. A 3300pF ceramic disk capacitor rated for 2kV would be an appropriate choice if I'm feeding two 600VA transformers from the mains, is that right? It looks like perhaps a TDK CK45-B3DD332K in the picture but I may get the Vishay 564R20TSD33 for the additional clearance. Either of these parts would be appropriate for C9 yeah? Thanks!
Those are not safety caps. They have to be X or X/Y rated when across the mains.
https://www.mouser.com/ProductDetai...Y1332M57Y5UC63L0/?qs=l7cgNqFNU1iaumQu9PQ69Q==
https://www.mouser.com/ProductDetai...Y1332M57Y5UC63L0/?qs=l7cgNqFNU1iaumQu9PQ69Q==
Both 6L6 and I answered question 1 before. Wrt question 2, the CL60s serves a few functions. It is all in the name: inrush current limiter. It limits the current suring startup, so that your tranny does not blow/set off a fuse, and also and possibly equally important: saves your caps from the biggest inrush currents from the transformer itself. When a tranny starts up, ot can act almost like a short circuit on the mains fuse.
The NTC works by providing resistance when cold, and less when warm, in effect not strangling the amp whilst playing music.
I would recommend you read all about the supply in Nelsons F5T manual. Also, the BA-2 manual had some nice info on a similar supply. It is all there, though I too found a bit much to grasp in the beginning.
The NTC works by providing resistance when cold, and less when warm, in effect not strangling the amp whilst playing music.
I would recommend you read all about the supply in Nelsons F5T manual. Also, the BA-2 manual had some nice info on a similar supply. It is all there, though I too found a bit much to grasp in the beginning.
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I don't think you have much to apologize for Wessideg! This thread is 67 pages long, the F5T builders thread is now 501 pages long. Forums like these, while an awesome place for smart people to chat, aren't that conducive to searching, and FINDING answers. Anyone have pointers for searching, I'm all ears! I'm much more a fan of wiki's.
This one, Wiki
Is just rarely used.
This one, Wiki
Is just rarely used.
Agree with MrDrewk. Don’t apologize for asking! I ask a lot myself, probably way too much. But then, asking creates answers someone else might be searching for. So it is win-win. the reason I pointed you towards Nelson articles, is I have found that a lot of my questions are almost always answered in the articles. If not, someone smart or even Nelson himself has written about it either in older articles (passdiy.com) or in this very forum, as far back as 2003 and thereabouts.
But it can be a web, finding answers for everything one ponders over in a build. Luckily this forum is full of great people.
Hope everything works out, and never hesitate to ask!
I’m asking for your opinion about balanced to unbalanced conversion for F5T v3 in monoblocks configuration. I run 4m long interconnects and I thing that differential architecture will help me to get rid of potential RF/EMI pickup. To make each monoblock classically balanced (means doubled it like two chanes in each) isn’t practical due to $ and mostly size. On other hand, all my sources are “truth balanced” and why not to utilize that..
So, how about that one? Very simple, relatively cheap and low distortion. I think it is based on Rod’s Elliott concept described in his relevant article.
Mono Balanced to Unbalanced Audio Line Converter Adapter ULTRA LOW NOISE | eBay
So, how about that one? Very simple, relatively cheap and low distortion. I think it is based on Rod’s Elliott concept described in his relevant article.
Mono Balanced to Unbalanced Audio Line Converter Adapter ULTRA LOW NOISE | eBay
PSUs are not concern for me since I already have 12V and 24V single pole PSUs in monoblocks that serve my soft start and speaker protection circuits.
I have similar Jansen for GND isolation. These are nice, but THD is way higher vs. this one that is based on OPAMPs.
Okay-
For Q7 & Q8 I somehow have 2 options in front of me:
Replacing 2sc4793: TIP31AG or MJE15034G?
Replacing 2SA1837: TIP32AG or MJE15035G?
Sorry, it’s been a few months since I put this on pause. In one of the BOMs, there is a ‘230V, 1A’ note that is confusing me, as neither of the options I listed seem to comply. Thanks,
Wes
For Q7 & Q8 I somehow have 2 options in front of me:
Replacing 2sc4793: TIP31AG or MJE15034G?
Replacing 2SA1837: TIP32AG or MJE15035G?
Sorry, it’s been a few months since I put this on pause. In one of the BOMs, there is a ‘230V, 1A’ note that is confusing me, as neither of the options I listed seem to comply. Thanks,
Wes
Will this 500w $50 Amazon special variac do the trick for powering up safely?
YaeCCC Auto Voltage Transformer AC Variable Voltage Converter Transformer 110VAC Input, 0-130VAC (500W) https://www.amazon.com/dp/B076Y2XHRS/ref=cm_sw_r_cp_api_glt_fabc_HZPPC3PKBME9WXFSYCRT
YaeCCC Auto Voltage Transformer AC Variable Voltage Converter Transformer 110VAC Input, 0-130VAC (500W) https://www.amazon.com/dp/B076Y2XHRS/ref=cm_sw_r_cp_api_glt_fabc_HZPPC3PKBME9WXFSYCRT