Just finish my first JLH-2005. The circuit is from this link:
The Class-A Amplifier Site - JLH Class-A Update
schematic and pcb attached.
A few thought about the design
1. The original 1969 design use 2N3055 as Q1 and Q2. Then changed to MJ15003. I'm thinking of some other subsititutes such as 2N3773, MJ21194 or 2SC5200
2. Can I use 2SA1358 as replacement of BD140? it's complementary of 2SC3421.
3. How to set the value of VR1, VR2 and VR3? in other words, what current should those 3 current sources be?
4. Is the large polygon pour on PCB good for audio amplifier?
The Class-A Amplifier Site - JLH Class-A Update
schematic and pcb attached.
A few thought about the design
1. The original 1969 design use 2N3055 as Q1 and Q2. Then changed to MJ15003. I'm thinking of some other subsititutes such as 2N3773, MJ21194 or 2SC5200
2. Can I use 2SA1358 as replacement of BD140? it's complementary of 2SC3421.
3. How to set the value of VR1, VR2 and VR3? in other words, what current should those 3 current sources be?
4. Is the large polygon pour on PCB good for audio amplifier?
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