Is the 1N5817 at D6 on the new GreenBean board just a polarity protection diode? If so, can I use a 1N4001? I have no 1N5817s but a billion 1N4001s.
Seems like the answer was yes for another Madbean board when someone asked a similar question, but I want to make sure.
As shottky diodes have lower forward voltages the remaining voltage level after the diode is higher than using normal diodes.
1n5817: 9V - 0.45v. = 8.55v
1n4001: 9v - 1v = 8v
Thanks for replying, Thomas. Can you help me apply that information? Does this mean that the voltage getting into the circuit after the diode will be too low with a 1n4001?
Hmm, not sure about too low but you want as much voltage at your circuit as possible.
I dont want to make this an theoretical approach but it depends on your expectations.
If you want it as close to an original tubescreamer you want close to 9V at your circuit.
If you are fine with Brians approach -the green bean- use the schottky as he tested it with this configuration.
Also the higher the circuit voltage the more headroom you have meaning that there is more clean range in your pedalsound.
So, from theory to practical advise: i would use the schottky diode or a jumper in its place. If you do the jumper you still can solder the 1n4001 diode across your power jack. Thats another way of protection used in other pedals. Just make sure the diode ring goes to plus 9v then or you will harm your power supply.
+1 on everything brought to the table by Thomas.
Most of the DIY layouts and even commercial pedals will use 1N4001 diodes for polarity protection mostly due to their availability and cost.
In the PSU section of the GreenBean there's also a low value resistor value in serie with power wich also decrease the mA going to the circuit itself, a CLR in fact.
Using the 1N51817 is simply to make sure you have sufficient power going to the circuit while offering protection. I build all my TS using 1N4001 and they sound good.
If you want the ultimate in protection and close to no power draw, UF4008 diodes are the way to go, used in many amps for rectifying the AC into DC.