I am a schematic hunter, a schematic colector...have 30231 units.
I am an amplifier tester too... like to assemble and test.... and junk and shot it with .12 gauge.
Some of them makes me happy...JLH, and JLH and the other one is a JLH design...all them class A.... some other makes some impressive sound too...but...99 percent!....BOOOOOOM!
I am a Broadcasting Television Professional, skilled to work in every post inside a TV Station.... from the equipments operation to design, construct, modify, install equipments, repair them, adjust.... one man television... i can do it.
But never studie audio.... i am ignorant...only good years....hearing music (hears, years...do not know)
I am seeing some times...DIODES in the positive rail, sometimes both rails...what are they doing there?
To avoid return patch?
To make some 0.6 constant potencial difference....
To isolation from power to input circuit?
Can you explain me please... this seems to be some trick to my ignorance.
regards,
Carlos
I am an amplifier tester too... like to assemble and test.... and junk and shot it with .12 gauge.
Some of them makes me happy...JLH, and JLH and the other one is a JLH design...all them class A.... some other makes some impressive sound too...but...99 percent!....BOOOOOOM!
I am a Broadcasting Television Professional, skilled to work in every post inside a TV Station.... from the equipments operation to design, construct, modify, install equipments, repair them, adjust.... one man television... i can do it.
But never studie audio.... i am ignorant...only good years....hearing music (hears, years...do not know)
I am seeing some times...DIODES in the positive rail, sometimes both rails...what are they doing there?
To avoid return patch?
To make some 0.6 constant potencial difference....
To isolation from power to input circuit?
Can you explain me please... this seems to be some trick to my ignorance.
regards,
Carlos
Thank you Hits, this use i already know..but you was kind to inform some.
HELLO people!...... 30 hits in a matter of seconds....
Please...let me know what you think?
Cannot be a trick, despite it smells a trick sometimes...but may have a good and reasonable reason.
Not to discharge some condenser?
To keep 0.6 drop constant?
To avoid some return (of what?....not a radio frequency transmiter...is an audio amplifier!)
Why sometimes only in one of the rails
Why not only resistor...because voltage drop variates with current...but input current variate a little...very small variations!... a cap can control that!
You that is reading..... a lot of hit!...i am seeing people is visiting the thread...PLEASE HELP!
Save big Charlie from the deep ignorance!
regards,
Carlos
HELLO people!...... 30 hits in a matter of seconds....
Please...let me know what you think?
Cannot be a trick, despite it smells a trick sometimes...but may have a good and reasonable reason.
Not to discharge some condenser?
To keep 0.6 drop constant?
To avoid some return (of what?....not a radio frequency transmiter...is an audio amplifier!)
Why sometimes only in one of the rails
Why not only resistor...because voltage drop variates with current...but input current variate a little...very small variations!... a cap can control that!
You that is reading..... a lot of hit!...i am seeing people is visiting the thread...PLEASE HELP!
Save big Charlie from the deep ignorance!
regards,
Carlos
Depends on where you put them. Sometimes they are used to isolate an input stage or driver stage from the power stage. The power supply is connected to the power stage, then via a series diode the input stage is powered from the same supply. After the diode an additional elcap is used. If, during transients or just big signals, the power supply of the output stage drops, the diode prevents that the elcap of the input stage is being discharged via the power stage. In this way the input stage keeps a more stable supply voltage.
So, yes, as you suggested, to avoid a return path.
The use of series diodes to create additional voltage drop because the original supply voltage is too low is bad design practice. They do not help a lot, they heat up, efficiency decreases, etc. Then it is better to use a simple pass regulator.
Steven
So, yes, as you suggested, to avoid a return path.
The use of series diodes to create additional voltage drop because the original supply voltage is too low is bad design practice. They do not help a lot, they heat up, efficiency decreases, etc. Then it is better to use a simple pass regulator.
Steven
Interesting, how the difficult things turn simple with a good teacher
Twenty years ago, as a HAM i was working with cable and some instalations, helping friends and someday one question appeared to me.
How the radio frequency energy...voltage.... turns into magnetic?...how the electron... the radio frequency electrons.... in a 30 Megahertz frequency can understand were is the cable and were is the aerial, the antenna.
Because if you separate the cable shild to left side.... and the internal wire to the rigth side....if you respect the wave length, there's one aerial (antenna)
And so simple the answer one enginneer told me.
Insulation.... the electric signal creates some magnetic field..but it is insulated by the shield..... and cannot propagate, cannot irradiate.... when you remove the shield...theres electromagnetical waves free to travel...so easy!.... after some good man has the good will to explain.
regards,...thanks again Steve
Carlos
Twenty years ago, as a HAM i was working with cable and some instalations, helping friends and someday one question appeared to me.
How the radio frequency energy...voltage.... turns into magnetic?...how the electron... the radio frequency electrons.... in a 30 Megahertz frequency can understand were is the cable and were is the aerial, the antenna.
Because if you separate the cable shild to left side.... and the internal wire to the rigth side....if you respect the wave length, there's one aerial (antenna)
And so simple the answer one enginneer told me.
Insulation.... the electric signal creates some magnetic field..but it is insulated by the shield..... and cannot propagate, cannot irradiate.... when you remove the shield...theres electromagnetical waves free to travel...so easy!.... after some good man has the good will to explain.
regards,...thanks again Steve
Carlos
Hi destroyer X,
Just for fun, thinking about radio frequency energy, areals and loops, turning electromagnetic fields into light:
http://www.rebix.nl/eng/ind-leds.html
The same company is also in Class D, BTW.
Steven
Just for fun, thinking about radio frequency energy, areals and loops, turning electromagnetic fields into light:
http://www.rebix.nl/eng/ind-leds.html
The same company is also in Class D, BTW.
Steven
Estoy in Pernambuco State, around the State Capital
5 miles at south related to Recife, Capital of Pernambuco State, in the Brazil Northeast, along the Boa Viagem beach,going south direction.
I born in Rio de Janeiro, and lived there till i complete 42 years old.
Now i have 53 years old, last 11 years here in Northeast, marriage second time, with a spanish damn lady, nervous and boring as a hell....but i like her this way she is....crazy...Yes!
Her family is from Spain, Orenz Barbadannes, we all have Spanish Passport to scape from here if things turns worst.
Hermano di mendoza, hermano del Mercosul, bienvenido!
Brother from Mendoza, Mercosul Brother, Welcome!
bye
Carlos
5 miles at south related to Recife, Capital of Pernambuco State, in the Brazil Northeast, along the Boa Viagem beach,going south direction.
I born in Rio de Janeiro, and lived there till i complete 42 years old.
Now i have 53 years old, last 11 years here in Northeast, marriage second time, with a spanish damn lady, nervous and boring as a hell....but i like her this way she is....crazy...Yes!
Her family is from Spain, Orenz Barbadannes, we all have Spanish Passport to scape from here if things turns worst.
Hermano di mendoza, hermano del Mercosul, bienvenido!
Brother from Mendoza, Mercosul Brother, Welcome!
bye
Carlos
Ha, ha, ha.
Pernambuco means "leg in hole" (perna em buco)? Or is it a deformation of the indian terms "Paraná Mbu"?
I love Brazil, I were there two times for vacation. Florianopolis, Camboriú, Porto Alegre (quite south)
I wish I could visit Sao Pablo or Rio. Perhaps some day.
Saúdos, amigo!
Pernambuco means "leg in hole" (perna em buco)? Or is it a deformation of the indian terms "Paraná Mbu"?
I love Brazil, I were there two times for vacation. Florianopolis, Camboriú, Porto Alegre (quite south)
I wish I could visit Sao Pablo or Rio. Perhaps some day.
Saúdos, amigo!
Very good my friend, you already know the meaning.
The first name was Paranambuco.... the origin was an native india name..... and was changing with time.... also English words for all (party) to forró (party rithm).... a la derrière from french...go backwards tuns into a la riêr.... and many words, some of them from Spanish too...as Gaúcho... as i like to say...we are the world, alike USA and others countries, we are result of natural genetic experience...the result is this one you see...many qualities and many defects too.
You were welcome brother, despite we have some competition, some healthy competition between our countries, we like you and our feelings is alike some brotherhood...and brothers can figth and disagree sometimes...no problem... bienvenido hermano.
regards,
Carlos
The first name was Paranambuco.... the origin was an native india name..... and was changing with time.... also English words for all (party) to forró (party rithm).... a la derrière from french...go backwards tuns into a la riêr.... and many words, some of them from Spanish too...as Gaúcho... as i like to say...we are the world, alike USA and others countries, we are result of natural genetic experience...the result is this one you see...many qualities and many defects too.
You were welcome brother, despite we have some competition, some healthy competition between our countries, we like you and our feelings is alike some brotherhood...and brothers can figth and disagree sometimes...no problem... bienvenido hermano.
regards,
Carlos
Re: Interesting, how the difficult things turn simple with a good teacher
Carlos,
sometimes the shield can cary the power refelected back from the antenna and become part of the antenna also.... ...something to think about.
Steven,
I design and build the hardware to do that same thing at work on a daily basis... ...all it is, is an air core transformer. The power supply is a little trickier
-Dan
destroyer X said:
Steven said:
Carlos,
sometimes the shield can cary the power refelected back from the antenna and become part of the antenna also.... ...something to think about.
Steven,
I design and build the hardware to do that same thing at work on a daily basis... ...all it is, is an air core transformer. The power supply is a little trickier
-Dan
Yes, and sometimes people try to "repair" that problem cutting cable's length
Sometimes a mismatch between the load (aerial) and the coaxial cable happened as a result of the wrong tunned aerial...this way, the cable start to work as a impedance transformer, and people start to cut it's length to try to "match"....no match is possible this way...the cable and antenna turns to some "system"..ressonating together... antenna (aerial) and cable ressonating together.... receiving and transmitting together as one.
I was trying to applied this to audio, and interesting result i found, and hard work i had.
The interesting result is that a real mismatch is founded with those normal values you find in amplifier output...the zobel and the coil forms together one filter, or better than that, one couplind transformer, or if you prefer one "ressonator"..... and the mismatch is there to be measured by a directional meter, alike one standing wave ratio meter..... the meter was difficult to make, and also to adjust..... and to make it zero with a 8 ohms load and a audio generator.... the filter... the zobel and the coil was change to a double greek letter "P".... two zobel and a coil in the middle, air core coil, and the values where so crazy i have not courage to say it here.
The most instesting is that MR. Graham Maynard, could discover that, and i suppose he did not use some directional coupler, some mismatch meter.... those things is hard to see as the theorical result is difference in phase, between the voltage and the current...but Graham used what he called a low impedance load to high frequencies.... he said the amplifier had a load to high frequencies.... either without the speaker, his zobel filter values resulted in some low impedance to hi frequencies, and the result was a non oscilating amplifier...if started to oscilate....different dimensioned zobel "sucks" the ultrasonic directly into the ground patch... and i found the same value he found in the first zobel..... but i have not courage to say the coil inductance and the second zobel values.....sorry, too much different from standard values.
And the result!!!...i coud not hear the result....have to use some spectrum analiser to see the harmonics and have to watch carefully magnified square wave forms...i could no perceived, and sent the material to one scientist, one wonderfull researcher in the other world side related to me, this man is a little shy, will not tell his name.
Of course the amplifier output impedance is lower than the load, this way, the filter and the coil is working alike one transformer too, not only filtering highs...have another use...i could measure that the values "standard" were not adequated..... a lot of mismatch i found in two amplifiers i tested.... returning energy was bigger than 50 percent!...i could reduce them to 15 percent...but this is only some technological dream, as i could not perceive audio differences...i could not!...maybe someone other can perceive some detail.
If i perceive some interest in that matter i will try to find the scratches of the standing wave meter made to audio frequencies....it may be somewhere in my computer...or the
scientist maybe have it with him.
I am seeing strange diodes positions in amplifiers, i will collect them to put as questions here.
regards.
Carlos
Sometimes a mismatch between the load (aerial) and the coaxial cable happened as a result of the wrong tunned aerial...this way, the cable start to work as a impedance transformer, and people start to cut it's length to try to "match"....no match is possible this way...the cable and antenna turns to some "system"..ressonating together... antenna (aerial) and cable ressonating together.... receiving and transmitting together as one.
I was trying to applied this to audio, and interesting result i found, and hard work i had.
The interesting result is that a real mismatch is founded with those normal values you find in amplifier output...the zobel and the coil forms together one filter, or better than that, one couplind transformer, or if you prefer one "ressonator"..... and the mismatch is there to be measured by a directional meter, alike one standing wave ratio meter..... the meter was difficult to make, and also to adjust..... and to make it zero with a 8 ohms load and a audio generator.... the filter... the zobel and the coil was change to a double greek letter "P".... two zobel and a coil in the middle, air core coil, and the values where so crazy i have not courage to say it here.
The most instesting is that MR. Graham Maynard, could discover that, and i suppose he did not use some directional coupler, some mismatch meter.... those things is hard to see as the theorical result is difference in phase, between the voltage and the current...but Graham used what he called a low impedance load to high frequencies.... he said the amplifier had a load to high frequencies.... either without the speaker, his zobel filter values resulted in some low impedance to hi frequencies, and the result was a non oscilating amplifier...if started to oscilate....different dimensioned zobel "sucks" the ultrasonic directly into the ground patch... and i found the same value he found in the first zobel..... but i have not courage to say the coil inductance and the second zobel values.....sorry, too much different from standard values.
And the result!!!...i coud not hear the result....have to use some spectrum analiser to see the harmonics and have to watch carefully magnified square wave forms...i could no perceived, and sent the material to one scientist, one wonderfull researcher in the other world side related to me, this man is a little shy, will not tell his name.
Of course the amplifier output impedance is lower than the load, this way, the filter and the coil is working alike one transformer too, not only filtering highs...have another use...i could measure that the values "standard" were not adequated..... a lot of mismatch i found in two amplifiers i tested.... returning energy was bigger than 50 percent!...i could reduce them to 15 percent...but this is only some technological dream, as i could not perceive audio differences...i could not!...maybe someone other can perceive some detail.
If i perceive some interest in that matter i will try to find the scratches of the standing wave meter made to audio frequencies....it may be somewhere in my computer...or the
scientist maybe have it with him.
I am seeing strange diodes positions in amplifiers, i will collect them to put as questions here.
regards.
Carlos
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