Please, a question: Someone has tested the famous Zener in
oscilloscope? My question is for the very poor frequency
response of the amplifier at this diagram. No helping so much at
high frequencies. The 470 pF miller capacitors could be reduced
its value to improve the frequency but the problem could be
serious if it starts to oscillate. Who can say something about
it?
oscilloscope? My question is for the very poor frequency
response of the amplifier at this diagram. No helping so much at
high frequencies. The 470 pF miller capacitors could be reduced
its value to improve the frequency but the problem could be
serious if it starts to oscillate. Who can say something about
it?
An externally hosted image should be here but it was not working when we last tested it.
The best way is to build it and try it.
If the frequency response is poor you can change caps as you suggest.
The 10pf caps could be changed too.
The front end is very similar to an old Hitachi lateral mosfet datasheet circuit.
I have used it a few times and had good results.
I added decoupling to the power supply front end to reduce no signal hum from the power supply.
If the frequency response is poor you can change caps as you suggest.
The 10pf caps could be changed too.
The front end is very similar to an old Hitachi lateral mosfet datasheet circuit.
I have used it a few times and had good results.
I added decoupling to the power supply front end to reduce no signal hum from the power supply.
Its like I said and is based on a lateral mosfet circuit hence no Vbe multiplier.
A Vbe multiplier would vastly improve thermal stability.
Is it famous?
- As Sajti just mentioned - TIP41/42 drivers will not survive the full swing with +/-70V rails. In addition - they are slow (may add stability issues).
- No bias spreader - also mentioned already. Any simple single-transistor (TO-126) will do.
- LTP's long tail arrangement - voltage regulator plus resistor - does not make too much sense. CCS will work much more efficiently here (requires pnp transistor, e.g. 2n5401).
In general - you may want to take something less "problematic" as a basis for your amplifier
Thanks vzaichenko for replying, however, I clarify something:
This amplifier as I published works and it is marketed in my country. The reason of my question here in this forum is whether someone has tested it with oscilloscope, because I noticed the naked ear deficiency in the frequency response, specially at high frequencies. The design theme is an apart thing.
This amplifier as I published works and it is marketed in my country. The reason of my question here in this forum is whether someone has tested it with oscilloscope, because I noticed the naked ear deficiency in the frequency response, specially at high frequencies. The design theme is an apart thing.
How come this amplifier is famous and who was the one who said that ?
To my understanding this is a schematic that has been canibalized by someone that didnt have available the right parts...
For example TIP41 is far too slow to need 470pf Miller cap actually with such a slow transistor it could be very easy to operate even with no miller caps at all .
anyone thinks that is possible to operate a driver for 4 outputs without base stoppers at this conditions originally made for 100 V at rails 70+70V ??? No way
This is famous joke not a famous amp
To my understanding this is a schematic that has been canibalized by someone that didnt have available the right parts...
For example TIP41 is far too slow to need 470pf Miller cap actually with such a slow transistor it could be very easy to operate even with no miller caps at all .
anyone thinks that is possible to operate a driver for 4 outputs without base stoppers at this conditions originally made for 100 V at rails 70+70V ??? No way
This is famous joke not a famous amp
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