"So I need not drive to Conrad tomorrow, Krachkiste, and can use my 16V caps?
Best regards - Rudi "
If thats the conclusion you draw for you from my measurement results, then you won't have to drive.
Do the measurement on your caps to see where they break through in reverse polarisation.
If this breakthough voltage (absolute value, no minus!) + the voltage rating of the cap (e.g. 16V) is sufficiently greater than the supply rail voltage you should be safe.
Best regards - Rudi "
If thats the conclusion you draw for you from my measurement results, then you won't have to drive.
Do the measurement on your caps to see where they break through in reverse polarisation.
If this breakthough voltage (absolute value, no minus!) + the voltage rating of the cap (e.g. 16V) is sufficiently greater than the supply rail voltage you should be safe.
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Netlist,
is this the nonsense you want stopped?
before that K posted this
and followed up with
and Rudi says
What do we do with nonsense like this being advised to beginners who cannot yet know better?
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We all know (it has been pointed out a myriad times) that caps should not be used at higher voltages then rated. Nor should transistors or resistors or coils.
I see both sides, people who build and offer countless free hours and designs to the forum and others pointing at possible errors and flaws.
Its delightful to read a thread when both are symbiotic.
/Hugo
I see both sides, people who build and offer countless free hours and designs to the forum and others pointing at possible errors and flaws.
Its delightful to read a thread when both are symbiotic.
/Hugo
There's no technical error in my potentiometer...this was used in several
amplifiers...and they are working and no audio source was damaged...so....this is real world result..not "i think so" or "the book says"...a reality my dear friends .. this much more important than beliefs and some rigid rules....or status quo (stablishment)
If we go keeping ancient ideas without try options....criticising new ideas and approaches..them we would still believing the world is square...and beyong the horizon there are monsters that eat entire ships.
We usually do not keep the potentiometer cursor at ground...because this does not make sense...amplifier is to produce audio, so, at least you have some resistance to ground...and more than 100 ohms, usually does not let transistors burn... even if they have not DC blocking condensers..... you have always some resistance to ground.... this is real world practice...day by day real sittuation.
Muting circuits shorts output and stages to ground too without damage.... do not worry about that....people twist things and confuses because they want..if you think about you gonna see this is not that problem.
Also...you can install in a different way if you want....not with my blessing but you can of course... you're free to decide...up to you folks!
If you feel afraid..them install a series resistance into the potentiometer wipe, the cursor... them no short to ground will be possible...just that.
All that noise has other reasons than technicall perfectionism.... and all of you are watching this clearly.
regards,
Carlos
amplifiers...and they are working and no audio source was damaged...so....this is real world result..not "i think so" or "the book says"...a reality my dear friends .. this much more important than beliefs and some rigid rules....or status quo (stablishment)
If we go keeping ancient ideas without try options....criticising new ideas and approaches..them we would still believing the world is square...and beyong the horizon there are monsters that eat entire ships.
We usually do not keep the potentiometer cursor at ground...because this does not make sense...amplifier is to produce audio, so, at least you have some resistance to ground...and more than 100 ohms, usually does not let transistors burn... even if they have not DC blocking condensers..... you have always some resistance to ground.... this is real world practice...day by day real sittuation.
Muting circuits shorts output and stages to ground too without damage.... do not worry about that....people twist things and confuses because they want..if you think about you gonna see this is not that problem.
Also...you can install in a different way if you want....not with my blessing but you can of course... you're free to decide...up to you folks!
If you feel afraid..them install a series resistance into the potentiometer wipe, the cursor... them no short to ground will be possible...just that.
All that noise has other reasons than technicall perfectionism.... and all of you are watching this clearly.
regards,
Carlos
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Yes... i think so.... they had a good idea.... optional feature
So, the one want that or other way can make it .... both options.... "L" adaptor and no adaptor...Universal feature to all kind of taste.... transistor above, transistor below... power transistor connect using wires....so....very good that.
Congratulation Omar and Rudi
regards,
Carlos
So, the one want that or other way can make it .... both options.... "L" adaptor and no adaptor...Universal feature to all kind of taste.... transistor above, transistor below... power transistor connect using wires....so....very good that.
Congratulation Omar and Rudi
regards,
Carlos
Regarding C1 and C1* rated voltage, I would advise everyone to use 16V capacitors maximum, if you use electrolytic types.
I don't know if you are aware of this, but electrolytic capacitors only start working properly when they are under a voltage of at least 10% of it's rated voltage.
So, this capacitors are in series with the input signal. Considering a 1V RMS input, then it's much better to use a capacitor that's rated for 10V. Otherwise, proper functioning is not guaranteed.
Film capacitors don't show this behaviour, and are much better for audio portions of the circuit. Using film capacitors here is much better than electrolytic.
Again, don't use hihger voltage electrolytic capacitors for the input capacitors. Stay at 16V tops!
AndrewT can confirm what I just said.
I don't know if you are aware of this, but electrolytic capacitors only start working properly when they are under a voltage of at least 10% of it's rated voltage.
So, this capacitors are in series with the input signal. Considering a 1V RMS input, then it's much better to use a capacitor that's rated for 10V. Otherwise, proper functioning is not guaranteed.
Film capacitors don't show this behaviour, and are much better for audio portions of the circuit. Using film capacitors here is much better than electrolytic.
Again, don't use hihger voltage electrolytic capacitors for the input capacitors. Stay at 16V tops!
AndrewT can confirm what I just said.
Define "working properly"
The electrolytic caps I use all work to my satisfaction at every voltage from 0V to the voltage rating of the cap.
This youtube video shows what can happen if you stress a 10V rated cap to 22V.
YouTube - capacitor explosion 10V 220uF
There are lots of such videos.
If you like fireworks and the smell of sulfidic acid in your living room, listen to Mitchel.
The electrolytic caps I use all work to my satisfaction at every voltage from 0V to the voltage rating of the cap.
This youtube video shows what can happen if you stress a 10V rated cap to 22V.
YouTube - capacitor explosion 10V 220uF
There are lots of such videos.
If you like fireworks and the smell of sulfidic acid in your living room, listen to Mitchel.
krachkiste,
I never said to use a capacitor over it's rated voltage. In fact, you should always leave a safety margin of 20%.
What I said is that when you use electrolytic capacitors on signal path, considering that the signal is about 1V RMS, you should use the lowest voltage rated capacitor you can find, preferably 10V.
Don't you put words in my mouth, as I never said what you think I said ...
I never said to use a capacitor over it's rated voltage. In fact, you should always leave a safety margin of 20%.
What I said is that when you use electrolytic capacitors on signal path, considering that the signal is about 1V RMS, you should use the lowest voltage rated capacitor you can find, preferably 10V.
Don't you put words in my mouth, as I never said what you think I said ...
Mitchel:
"krachkiste,
I never said to use a capacitor over it's rated voltage. In fact, you should always leave a safety margin of 20%.
What I said is that when you use electrolytic capacitors on signal path, considering that the signal is about 1V RMS, you should use the lowest voltage rated capacitor you can find, preferably 10V.
Don't you put words in my mouth, as I never said what you think I said ... "
The application we are talking about is Rudis DC protection. This protection must survive the conditions it is exposed to. In this case it is supposed to protect the speaker under all circumstances including the full rail voltage over these 2 caps. You say yourself, capacitors are not to be used over their rated voltage. Yet you propose to do so in this application.
Still, what is the explanation for that I "should use the lowest voltage rated capacitor you can find" in the context of your post.
What happens if I didn't?
"krachkiste,
I never said to use a capacitor over it's rated voltage. In fact, you should always leave a safety margin of 20%.
What I said is that when you use electrolytic capacitors on signal path, considering that the signal is about 1V RMS, you should use the lowest voltage rated capacitor you can find, preferably 10V.
Don't you put words in my mouth, as I never said what you think I said ... "
The application we are talking about is Rudis DC protection. This protection must survive the conditions it is exposed to. In this case it is supposed to protect the speaker under all circumstances including the full rail voltage over these 2 caps. You say yourself, capacitors are not to be used over their rated voltage. Yet you propose to do so in this application.
Still, what is the explanation for that I "should use the lowest voltage rated capacitor you can find" in the context of your post.
What happens if I didn't?
I don't want to be a bad egg , but here goes. When I first joined forum , I saw DX amps ,wanted to build. I have a hard time finding BC xxx parts here , have a lot of KSA/c's, Mpsa's, etc. I suggest maybe modifications to use different parts ,get shot down (told to only build it with BC's).
All the DX amps work , very well ... as they are based on simple 60's RCA design. This is another issue I see while visiting the DX amp site , These amps can not be copyrighted by "DX corp." , they are USA inventions the same as transistors and tubes and most everything else in the world!!!I acknowledge the "DX" part can be copyrighted (maybe ) but that is it . I got reamed out for just posting a ESP audio circuit , so why does Carlos get away with posting other peoples work like this one from Doug self ? Just replace all with BCxxx's and call it your own.
The good thing is that all amps work and will not burn down the house or oscillate (I have all the sims and most DX amps are overcompensated).
ALL THIS over one input level control...
OS
krachkiste,
Sorry, I thought you were talking about the input caps on the amplifier.
What I have learnt is that electrolytic capacitors work better if you use them under a voltage that is at least 10% of it's rated voltage.
So, if your voltage is 3V, you should use 35V capacitors, and not more. Again, if you're using it for audio signals of about 1V, you should use 10 or 16V capacitors, and not more.
What isn't good is using a 63V capacitor on a 1V signal circuit path.
Again, I don't recomend using a capacitor on a voltage that exceeds it's rated voltage. In fact, I always put a 20% margin of safety. Therefore, if the circuito is 40V, I will use a capacitor rated for at least 50V.
I will try to find a paper that confirms that, but I thought it was already common knowledge.
Sorry, I thought you were talking about the input caps on the amplifier.
What I have learnt is that electrolytic capacitors work better if you use them under a voltage that is at least 10% of it's rated voltage.
So, if your voltage is 3V, you should use 35V capacitors, and not more. Again, if you're using it for audio signals of about 1V, you should use 10 or 16V capacitors, and not more.
What isn't good is using a 63V capacitor on a 1V signal circuit path.
Again, I don't recomend using a capacitor on a voltage that exceeds it's rated voltage. In fact, I always put a 20% margin of safety. Therefore, if the circuito is 40V, I will use a capacitor rated for at least 50V.
I will try to find a paper that confirms that, but I thought it was already common knowledge.
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