hello, my name is fred i just discovered this forum i think it is going to be one of my favorites right now
well, i need your help please
here you can see one ECL86 mu-follower stage preamp schematic
i ve been told it was a very good one
so i ve been badly challenging me trying to make a basic 6 channel preamp with it, putting three of them in serial.
I ve already been able to design the circuit, but some questions remain unsolvable for my pour skills:
for the stereo preamp, the alim transfo characteristic is:
primary 220V
secondary: 2*220V 40mA
1*6.3V 1A
so i need a transfo with 2*220V 120mA and 3*6.3V 1A secondary,
right?
i know i could use a single 6.3V 3A but like this it is easyer to build the circuit
what i would like to know is, if someone can explain to me:
what component values are going to change?
i think R25, and C7-R27-C8 pi filter, but what will be their values?
please help!
thank you
frederic awaoki
you will find the schematic and the list of components here for an easier overall view
http://haute.fidelite.com.online.fr/DIY/LED-mu-follower/DIY-mu-follower.html
of course i give you the original values of all components:
- Résistances ±5 % 1 W
R1 - 2,7 KOhm
R2 - 150 Ohm
R3 - 220 kOhm
R4 - 1 kOhm
R5 - 180 Ohm
R6 - 15 kOhm (2 W)
R7 - 470 kOhm
R8 - 150 Ohm
R9 - 150 Ohm
R10 - 22 kOhm
R11 - 10 kOhm
R12 - 2,7 kOhm
R13 - 150 Ohm
R14 - 220 kOhm
R15 - 1 kOhm
R16 - 180 Ohm
R17 - 15 kOhm (2 W)
R18 - 470 kOhm
R19 - 150 Ohm
R20 - 150 Ohm
R21 - 22 kOhm
R22 - 10 kOhm
R23 - 47 Ohm
R24 - 47 Ohm
R25 - 150 kOhm
R26 - 47 kOhm
R27 - 2,2 kOhm (2 W)
- Condensateurs non polarisés
C1 - 0,22 µF / 250 V
C2 - 10 µF / 250 V
C3 - 2,2 µF / 400 V
(ou électrolytique 2,2 µF / 450 V)
C4 - 0,22 µF / 250 V
C5 - 10 µF / 250 V
C6 - 2,2 µF / 400 V
- Electrochimiques
C7 - 100 µF / 400 V (ou 385 V)
C8 - 220 µF / 400 V (ou 385 V)
C9 - 100 µF / 100 V
C10 - 1000 µF / 16 V
C11 - 1000 µF / 16 V
- Divers
T1-T2 : ECL86
P1-P2 : pot 22 kOhm or 47 kOhm Log
D1-D2 : 1N4007
TR1 : primaire : 220 V
secondaires :
- 2 x 220 V / 40 mA
- 1 x 6,3 V / 1 A
bye.
fred
well, i need your help please
here you can see one ECL86 mu-follower stage preamp schematic
i ve been told it was a very good one
so i ve been badly challenging me trying to make a basic 6 channel preamp with it, putting three of them in serial.
I ve already been able to design the circuit, but some questions remain unsolvable for my pour skills:
for the stereo preamp, the alim transfo characteristic is:
primary 220V
secondary: 2*220V 40mA
1*6.3V 1A
so i need a transfo with 2*220V 120mA and 3*6.3V 1A secondary,
right?
i know i could use a single 6.3V 3A but like this it is easyer to build the circuit
what i would like to know is, if someone can explain to me:
what component values are going to change?
i think R25, and C7-R27-C8 pi filter, but what will be their values?
please help!
thank you
frederic awaoki
you will find the schematic and the list of components here for an easier overall view
http://haute.fidelite.com.online.fr/DIY/LED-mu-follower/DIY-mu-follower.html
of course i give you the original values of all components:
- Résistances ±5 % 1 W
R1 - 2,7 KOhm
R2 - 150 Ohm
R3 - 220 kOhm
R4 - 1 kOhm
R5 - 180 Ohm
R6 - 15 kOhm (2 W)
R7 - 470 kOhm
R8 - 150 Ohm
R9 - 150 Ohm
R10 - 22 kOhm
R11 - 10 kOhm
R12 - 2,7 kOhm
R13 - 150 Ohm
R14 - 220 kOhm
R15 - 1 kOhm
R16 - 180 Ohm
R17 - 15 kOhm (2 W)
R18 - 470 kOhm
R19 - 150 Ohm
R20 - 150 Ohm
R21 - 22 kOhm
R22 - 10 kOhm
R23 - 47 Ohm
R24 - 47 Ohm
R25 - 150 kOhm
R26 - 47 kOhm
R27 - 2,2 kOhm (2 W)
- Condensateurs non polarisés
C1 - 0,22 µF / 250 V
C2 - 10 µF / 250 V
C3 - 2,2 µF / 400 V
(ou électrolytique 2,2 µF / 450 V)
C4 - 0,22 µF / 250 V
C5 - 10 µF / 250 V
C6 - 2,2 µF / 400 V
- Electrochimiques
C7 - 100 µF / 400 V (ou 385 V)
C8 - 220 µF / 400 V (ou 385 V)
C9 - 100 µF / 100 V
C10 - 1000 µF / 16 V
C11 - 1000 µF / 16 V
- Divers
T1-T2 : ECL86
P1-P2 : pot 22 kOhm or 47 kOhm Log
D1-D2 : 1N4007
TR1 : primaire : 220 V
secondaires :
- 2 x 220 V / 40 mA
- 1 x 6,3 V / 1 A
bye.
fred