ding
Well-known member
There are so many threads on this but I wanted to start a new one because the other ones are very old and not too detailed when it comes to p2p. My hopes is to document my build as I go along and hopefully it will be useful to someone.
I want to do my first p2p/tube project and I decided on this one. I've been reading alot about tube circuitry lately and a bit of it is taking me some time to digest. I am certainly not very informed on vari-mu compressors so I decided to start by learning Kicad and drawing up my first ever schematic to at least try to understand where I need to go and learn something useful. As things always go I did way too much reading and research and the original simple 436c started growing with mods and other things until it became not so simple any more. So I guess a schematic was a good idea after all.
Below is the schematic I did. I'm not sure If I went overboard or if I was able to implement all the mods correctly so hopefully someone will spot some of the many errors in there before I start on this.
Things I'm not sure of...
1a. Is the threshold implemented correctly?
1b. Do I even need a threshold (is it useful for this design)?
2a. Is the balance circuitry implemented properly (neon bulb/balance pot, etc.)?
2b. Do I even need the neon bulb balancing circuit? (is it problematic without it)?
3. What input transformer to use besides the very expensive Sowter 3575 (anything from Cinemag, US builder here)?
4. Are my output transformers outputs wired correctly with the CT? Do I even need to wire up the CT?
5. Do I need a 600r termination resistor accross the output transformer? (My guess is no. I guess I should really try this one and find out for myself when I build it)
Things I think are correct...
1. The 600 ohm T-bridged attenuator.
2. The attack switch and resistor values.
3. The recovery switch wiring.
Things I need to find out...
1a. What kind of meter to get? My guess is 1mA
1b. Should I put a pot to calibrate the meter?
2. What kind of fuse to use? No guesses on that one.
3. What are the voltage values of the resistors and capacitors. My guess is 1/4w resistors in the main circuit, 1w at the psu except for that 7k 5w resistor. Caps 350v all around.
EDIT: Removed schematic
I want to do my first p2p/tube project and I decided on this one. I've been reading alot about tube circuitry lately and a bit of it is taking me some time to digest. I am certainly not very informed on vari-mu compressors so I decided to start by learning Kicad and drawing up my first ever schematic to at least try to understand where I need to go and learn something useful. As things always go I did way too much reading and research and the original simple 436c started growing with mods and other things until it became not so simple any more. So I guess a schematic was a good idea after all.
Below is the schematic I did. I'm not sure If I went overboard or if I was able to implement all the mods correctly so hopefully someone will spot some of the many errors in there before I start on this.
Things I'm not sure of...
1a. Is the threshold implemented correctly?
1b. Do I even need a threshold (is it useful for this design)?
2a. Is the balance circuitry implemented properly (neon bulb/balance pot, etc.)?
2b. Do I even need the neon bulb balancing circuit? (is it problematic without it)?
3. What input transformer to use besides the very expensive Sowter 3575 (anything from Cinemag, US builder here)?
4. Are my output transformers outputs wired correctly with the CT? Do I even need to wire up the CT?
5. Do I need a 600r termination resistor accross the output transformer? (My guess is no. I guess I should really try this one and find out for myself when I build it)
Things I think are correct...
1. The 600 ohm T-bridged attenuator.
2. The attack switch and resistor values.
3. The recovery switch wiring.
Things I need to find out...
1a. What kind of meter to get? My guess is 1mA
1b. Should I put a pot to calibrate the meter?
2. What kind of fuse to use? No guesses on that one.
3. What are the voltage values of the resistors and capacitors. My guess is 1/4w resistors in the main circuit, 1w at the psu except for that 7k 5w resistor. Caps 350v all around.
EDIT: Removed schematic