^^ which reminds me ....... this one still empty, present idea being to put my own XA252 in
200C, as perfect to show 200dA
https://www.zenmod.in.rs/babelfish-most-probably-j2-b17-edition-case-for-future-amp/
Did you go to school during the Tito Regime?
That looks like one very industrial design for a simple enough consumer product.
Looks like something the Soviets would have done...
(1) Now we just need meters, MORE METERS. Like one power meter for each channel, with front panel switch for load impedance (4, 6, 8, 16 )... and two more meters for power supply voltage. And red lights when the protection circuit kicks in.
We must not let the ghosts of the Yugoslavian Central Design Bureau outdo us! @Gianluca.. Time to step up! Make some industrial front panels.
(2) I think we just coined a new term.... Umlaut Metal. The Heaviest of all. Think Hoff's masterpiece.. "Surfer Chicks From East Dusseldorf"... it has the best, heaviest, bombastic bass line...
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yup
though, human stupidity is just changing faces........
anyhow - supposedly case for some industrial choke/inductor
bought through on-line adds ........ proper junkyards are becoming rare .... and I stopped searching
have enough junk for one smaller proper junkyard
Tito.. meet Franco...
Although I left early enough, them priests taught the fear of God.... write that history paper, do that trig homework, do the French translations or you will go to Hell.
Tito... meet Nixon. ;-)
I am not a crook!
Back to the amps...
Although I left early enough, them priests taught the fear of God.... write that history paper, do that trig homework, do the French translations or you will go to Hell.
Tito... meet Nixon. ;-)
I am not a crook!
Back to the amps...
I powered up one channel, +-42 volts is present at +-U. My dc offset can be adjusted to 0, but no matter how many turns of P2 I can only get to 50 mv. I cant get less than 50 or more than 50. I tested at RT and it reads 1.5k ohms and doesnt change on each board. I have Bourns 3296W-1-501LF pots so they should only be 25 turns. Any ideas what I am missing here, at least there wasnt any smoke. Pucks dont seem to be getting warm either.
Attachments
Let me go over part of this board, going over every resistor and just noticed I put in a 120ohm resister instead of a 120kohm one at R**.
My dog is gonna go nuts when he smells that cat.
I better keep the amp high enough so he won't be tempted to "mark it" as his own.
Are you gonna ship the Tannoys too?
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Quick question. What fuse values/types are recommended for the IEC and the two donuts in these builds?
Cheers,
Soren
Cheers,
Soren
Soren,
For each donut: Fuse Size = Transformer VA / Mains voltage. Then pick the closest standard size.
Examples:
300VA / 120V = 2.5A slow blow fuse
400VA / 120V = 3.3333 So try a 3A or 3.5A fuse
For dual donut, have a fuse for each donut as above, plus a main fuse on the IEC that feeds both fuses/donuts.
Example: 2x300VA donuts = 2x2.5 = 5A fuse
For each donut: Fuse Size = Transformer VA / Mains voltage. Then pick the closest standard size.
Examples:
300VA / 120V = 2.5A slow blow fuse
400VA / 120V = 3.3333 So try a 3A or 3.5A fuse
For dual donut, have a fuse for each donut as above, plus a main fuse on the IEC that feeds both fuses/donuts.
Example: 2x300VA donuts = 2x2.5 = 5A fuse
separate fuse for each Donut
calc is simple - Donut VA/mains voltage, then first standard value
fuse Slow or T (Trage, "a" umlaut)
example - 400VA Donut, 120Vac mains
400/120=3.3A
take 3A15
that, if you have any sort of soft start ....... which is highly cunning to have
edit- now I see Boyz already replied, while I had page idling
calc is simple - Donut VA/mains voltage, then first standard value
fuse Slow or T (Trage, "a" umlaut)
example - 400VA Donut, 120Vac mains
400/120=3.3A
take 3A15
that, if you have any sort of soft start ....... which is highly cunning to have
edit- now I see Boyz already replied, while I had page idling
I also have some store soft start boards. I followed 6l6's build and used one on my BA3 Amp. Works great. Reading the info on those soft start, sounds like one would serve for two channels if only one power cord. Can I still use one for each channel using 2? Or, is there a good reason to use the CL60 setup?
Russellc
Russellc
Not only has it been cat marked... but do you know the audio exorcism required to undo the damage to electrolytic caps by playing Umlaut Heavy Metal? (*)
It will take a significant chunk of the extant discography of Iberian and Frankish Gregorian Chants to undo the damage.. That and two weeks of the Rat Pack live concerts,,,
(*) OTOH, if you're gonna test the behavior of an amp at clipping... nothing better than loud stuff with a dynamic range of 1 db. I guess.
It will take a significant chunk of the extant discography of Iberian and Frankish Gregorian Chants to undo the damage.. That and two weeks of the Rat Pack live concerts,,,
(*) OTOH, if you're gonna test the behavior of an amp at clipping... nothing better than loud stuff with a dynamic range of 1 db. I guess.
And here's the latest version. 😆
Belt drive.... of course... the best. Whiskey, bag pipe music and Belt Drives...
I think Jim's mad at me... we better back off the belt drives...
But it's OK, I'm happy Señor Mucho Macho SIT is playing tunes.
Belt drive.... of course... the best. Whiskey, bag pipe music and Belt Drives...
I think Jim's mad at me... we better back off the belt drives...
But it's OK, I'm happy Señor Mucho Macho SIT is playing tunes.
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@Russellc I had a similar question about soft start in another thread.
https://www.diyaudio.com/community/...ncludes-soft-start-h9kpxg.354971/post-7556477
I plan to use Mark's soft start board, but will likely use two ICLs as he suggested.
https://www.diyaudio.com/community/...ncludes-soft-start-h9kpxg.354971/post-7556477
I plan to use Mark's soft start board, but will likely use two ICLs as he suggested.