As you know Klaas, Nordic is kidding...and with some bad mood
because frustrated with this delay.
Well dear Nordic...you can hold your old heatsinks and borrow them for a while...than you will be able to listen while waiting.
A good chance you have to check your construction with care...measuring resistance from positive to minus, positive to ground and negative to ground...all resistances may be big....much more than 30K.....and invert your leads to produce one more resistance measurement.
Also you can give a tripple check in your transistor leads....electrolitic condensers polarities.
Also you can ajust the bias trimpot to zero ohms.....the off set one can be adjusted to 7900 ohms as a good starting point.
Check resistance from output to ground and input to ground...inverting the multimeter probe points polarity while doing.
Also you can observe, inspect, or watch your copper lines using lenses....also to test your supply under load conditions with resistances.
All those things will turn your amplifier a "plug and play"..alike it really is...easy and fast to adjust.
Bias first
Than off set
Return to adjust bias
Now re adjust off set.
READY!
regards,
Carlos
because frustrated with this delay.
Well dear Nordic...you can hold your old heatsinks and borrow them for a while...than you will be able to listen while waiting.
A good chance you have to check your construction with care...measuring resistance from positive to minus, positive to ground and negative to ground...all resistances may be big....much more than 30K.....and invert your leads to produce one more resistance measurement.
Also you can give a tripple check in your transistor leads....electrolitic condensers polarities.
Also you can ajust the bias trimpot to zero ohms.....the off set one can be adjusted to 7900 ohms as a good starting point.
Check resistance from output to ground and input to ground...inverting the multimeter probe points polarity while doing.
Also you can observe, inspect, or watch your copper lines using lenses....also to test your supply under load conditions with resistances.
All those things will turn your amplifier a "plug and play"..alike it really is...easy and fast to adjust.
Bias first
Than off set
Return to adjust bias
Now re adjust off set.
READY!
regards,
Carlos
Thanks for all the advice, actualy I'm feeling pretty confident in the manual part of the work, which was done painfully slowly over a number of days, with constant crosschecking etc... and I've build a few amps in the 40 to 60WPC range, so I feel pretty good proceduraly too. 
All copper traces were solder plated with flux and cleaned afterwards...
Do I need to make any adjustment for the BC640, apart from layout... confirmed legs with DMM and datasheet...
All copper traces were solder plated with flux and cleaned afterwards...
Do I need to make any adjustment for the BC640, apart from layout... confirmed legs with DMM and datasheet...
I remember i have found two different position of leads in that transistor
I have published something in Symassym thread...showing two brands with different base leads.
But, of course, you have checked....those BC639 (NPN) and (BC640) PNP... they can be used only in the differential....using it as VAS would explode as you know...hehe..i made that once!
Yes....i know you are experienced...but having spare time...good to use it checking things.
Well....i feel myself hardly experienced related practical work...hands on work...but now a days i still make some mistakes.
Last year i have made an interesting supply....it was something inside a case, inside an enclosure....but when soldering wires inside i made a mistake....my traditional positive wire, always colloured as red was inverted related the negative one...this made me burn precious parts...and this happened because experienced i was.
So strong was my belief that red is always positive that i did not have checked with the voltimeter...i just install the wires and i sent the amplifier that was earlier working fine..i have send it to hell...one way ticked...i have lost many parts because i am experienced......it is hard to believe in ourselves, this will be the trigger that will start foolishes.....my own experience.
Many thousand times before, red was always positive...i could never imagine that this time, "that wire coloured red", was not!
So, you see in this example, that non experienced beginners can make a better work than i can... as i have too much big belief in my experience.
regards,
Carlos
I have published something in Symassym thread...showing two brands with different base leads.
But, of course, you have checked....those BC639 (NPN) and (BC640) PNP... they can be used only in the differential....using it as VAS would explode as you know...hehe..i made that once!
Yes....i know you are experienced...but having spare time...good to use it checking things.
Well....i feel myself hardly experienced related practical work...hands on work...but now a days i still make some mistakes.
Last year i have made an interesting supply....it was something inside a case, inside an enclosure....but when soldering wires inside i made a mistake....my traditional positive wire, always colloured as red was inverted related the negative one...this made me burn precious parts...and this happened because experienced i was.
So strong was my belief that red is always positive that i did not have checked with the voltimeter...i just install the wires and i sent the amplifier that was earlier working fine..i have send it to hell...one way ticked...i have lost many parts because i am experienced......it is hard to believe in ourselves, this will be the trigger that will start foolishes.....my own experience.
Many thousand times before, red was always positive...i could never imagine that this time, "that wire coloured red", was not!
So, you see in this example, that non experienced beginners can make a better work than i can... as i have too much big belief in my experience.
regards,
Carlos
Which ones Klaas? sadly anything over .25W is carbon film *hides*
Destroyer you are correct, the version in Eagle is diffirent from the ones I bought...
Yep we are all human.... and I make no less mistakes than the next guy... its just that I think I fixed them all... Will post picture of transistor positions when done for you to check..., got to solder about 5 more components in.
Destroyer you are correct, the version in Eagle is diffirent from the ones I bought...
Yep we are all human.... and I make no less mistakes than the next guy... its just that I think I fixed them all... Will post picture of transistor positions when done for you to check..., got to solder about 5 more components in.
Nordic, please remember my comment 'to finish first, you first have to finish'.
You don't need fancy parts to finish
You can allways add those fancy parts later.
Get it working first.
Post pictures please .(or mail them, whatever)
Whenever i'm toying around in eagle, i always look on the net to find the pin-out. I use whatever device i can find inside the eagle-library that has the same housing and the same pinout.
With kind regards,
Klaas
You don't need fancy parts to finish
You can allways add those fancy parts later.
Get it working first.
Post pictures please .(or mail them, whatever)
Whenever i'm toying around in eagle, i always look on the net to find the pin-out. I use whatever device i can find inside the eagle-library that has the same housing and the same pinout.
With kind regards,
Klaas
Nope, have to wait to have physical sinks and transformers infront of me... in woodwork you quickly learn to measure reather than trust sales information... You can make stuff smaller, but not larger..
I took woodwork as a highschool subject, and built up quite a few tools over the years, as I have always been fond of working with wood, the smell and feel is wonderfull, you can tell many woods just by their smell... Orange tree wood smells EXACTLY like popcorn when it gets hot on a lathe or on a tablesaw, for instance...
When you sand the paper you use you eyes to look for imperfections and take care of them with love, like you would use your ear to listen for small things that are not quite right in your amp and polish it...
I just have very little space, so I always just make small things...
Always busy recycling tiny bits of scrap wood I pick up.
I made a new design last night which does not look so blocky, android like... was very impressed myself... kinda early eigties Blaupunkt look, and then stupid google sketchup crashed...
You must try that program, very small too for download, so easy you little girl will be able to figgure it out in minutes... those heatsinks in the old drawing, was the very first thing I drew.... thats how easy it is.
I took woodwork as a highschool subject, and built up quite a few tools over the years, as I have always been fond of working with wood, the smell and feel is wonderfull, you can tell many woods just by their smell... Orange tree wood smells EXACTLY like popcorn when it gets hot on a lathe or on a tablesaw, for instance...
When you sand the paper you use you eyes to look for imperfections and take care of them with love, like you would use your ear to listen for small things that are not quite right in your amp and polish it...
I just have very little space, so I always just make small things...
Always busy recycling tiny bits of scrap wood I pick up.
I made a new design last night which does not look so blocky, android like... was very impressed myself... kinda early eigties Blaupunkt look, and then stupid google sketchup crashed...
You must try that program, very small too for download, so easy you little girl will be able to figgure it out in minutes... those heatsinks in the old drawing, was the very first thing I drew.... thats how easy it is.
Go ahead, please, tell me the program name...that one you told something about
I have some problems to understand English.... i use to misunderstand a lot of things.
When listening people talking i have problems to understand USA guys...no way to understand them completelly...but from England i have no problems to listen and understand.
But i can understand Mr. Bush words...hehe..i think he use simple words all time long...they match my small vocabulary.
Please, inform if you were talking about some "drawing program"
regards,
Carlos
I have some problems to understand English.... i use to misunderstand a lot of things.
When listening people talking i have problems to understand USA guys...no way to understand them completelly...but from England i have no problems to listen and understand.
But i can understand Mr. Bush words...hehe..i think he use simple words all time long...they match my small vocabulary.
Please, inform if you were talking about some "drawing program"
regards,
Carlos
They will work great in that position Tweak.
Thank you to construct this amplifier.
Post images if you really decided to make it...after start to do some of course.
Also true opinions will be welcome..comparisons too.
Using better speed transistors in the driver position and VAS position, will turn interesting to use 20 picofarads or 22, 27, 33 picofarads in the Voltage amplifier position, from base to colector...and also to include the same value (from 20 to 33 picofarads) in parallel with your feedback resistor (the position you have 12 picofarads)... the same range of values...not needed to be the same value of capacitance used in the vas position.
High speed transistors are able to oscilate...or to help some oscilation that may start, beeing very cooperative and ressonating altogether...this way...to be carefull using Miller capacitor will be a needed behavior.
Possible oscilations can be measured from the output line to ground, and as you may know, they are AC voltages that will be developed over the load (speaker or resistance)...normally they are high in voltage amplitude.... almost the same as maximum peak to peak output voltage...output transistors overheat and sound turns distorted or mufled....they normally do not stop if you short the input.
Using those capacitors, the possibility, the chance to have oscilation is very small...really very small...only bad luck can make this unit oscilate.
I am here...just call me if you have problems..i will be over your shoulder all time long.
You may be experienced...but i do not know...i have not magic capacities...sorry if you already know all the tips and tricks related audio amplifiers.
regards,
Carlos
Thank you to construct this amplifier.
Post images if you really decided to make it...after start to do some of course.
Also true opinions will be welcome..comparisons too.
Using better speed transistors in the driver position and VAS position, will turn interesting to use 20 picofarads or 22, 27, 33 picofarads in the Voltage amplifier position, from base to colector...and also to include the same value (from 20 to 33 picofarads) in parallel with your feedback resistor (the position you have 12 picofarads)... the same range of values...not needed to be the same value of capacitance used in the vas position.
High speed transistors are able to oscilate...or to help some oscilation that may start, beeing very cooperative and ressonating altogether...this way...to be carefull using Miller capacitor will be a needed behavior.
Possible oscilations can be measured from the output line to ground, and as you may know, they are AC voltages that will be developed over the load (speaker or resistance)...normally they are high in voltage amplitude.... almost the same as maximum peak to peak output voltage...output transistors overheat and sound turns distorted or mufled....they normally do not stop if you short the input.
Using those capacitors, the possibility, the chance to have oscilation is very small...really very small...only bad luck can make this unit oscilate.
I am here...just call me if you have problems..i will be over your shoulder all time long.
You may be experienced...but i do not know...i have not magic capacities...sorry if you already know all the tips and tricks related audio amplifiers.
regards,
Carlos
My spy have discovered that dear Klaas is cooking some nice
ideas....this image seems to me that Klaas will construct and enclosure for stereo Dx amplifier.
My pioneer related construction of Dx amplifier will construct more units.
Hummmmm, this shows to me, also my spy opinion, that he apreciated the amplifier sonics.
Dx amplifier has Klaas aproval!
regards and thank you my dear spy.
regards,
Carlos
ideas....this image seems to me that Klaas will construct and enclosure for stereo Dx amplifier.
My pioneer related construction of Dx amplifier will construct more units.
Hummmmm, this shows to me, also my spy opinion, that he apreciated the amplifier sonics.
Dx amplifier has Klaas aproval!
regards and thank you my dear spy.
regards,
Carlos
Attachments
Nordic..people had discovered, in Africa, a seed that is changing human taste
The seed is twice the coffee grain size...colour is redish brown.
When people smash it, tongue cells change it's sensitive behavior..in such way that you can eat entire lemmons, feeling it sweat..... normal milk with lemmon seems to be Chantilly cream..that wipped cream.
Hummm....go to plant those seeds in your place Nordic.
That magic will have customers.... it changes those tastes we do not like, producing others interesting tastes.
Already sold in China, smashed and mixed with some red colour and milk suggar (Lactosis)....Misterious fruit is the name i think.
ahahaha..you can inflate plastic with air...paint it yellow...and the guy having that seed in advance..will perceive that plastic as a nice cake make with a lot of eggs.
Only exploring people's curiosity, someone can make billions of dollares with some enterprise exploring those magic things.
Dx amplifier will continue to sound good..even to those folks that have eated that seed.... and maybe if someone decide to eat the board, it may taste good.
regards,
Carlos
The seed is twice the coffee grain size...colour is redish brown.
When people smash it, tongue cells change it's sensitive behavior..in such way that you can eat entire lemmons, feeling it sweat..... normal milk with lemmon seems to be Chantilly cream..that wipped cream.
Hummm....go to plant those seeds in your place Nordic.
That magic will have customers.... it changes those tastes we do not like, producing others interesting tastes.
Already sold in China, smashed and mixed with some red colour and milk suggar (Lactosis)....Misterious fruit is the name i think.
ahahaha..you can inflate plastic with air...paint it yellow...and the guy having that seed in advance..will perceive that plastic as a nice cake make with a lot of eggs.
Only exploring people's curiosity, someone can make billions of dollares with some enterprise exploring those magic things.
Dx amplifier will continue to sound good..even to those folks that have eated that seed.... and maybe if someone decide to eat the board, it may taste good.
regards,
Carlos
- Status
- Not open for further replies.