Hi Felipe,
Yes, it is OK with no volume control. But please break the wire from the Input to Ground, add 1M resistor.
This makes sure there is no charge in C3.
Yes, it is OK with no volume control. But please break the wire from the Input to Ground, add 1M resistor.
This makes sure there is no charge in C3.
Rod,
First of all thanks for support really appreciated, I have still several doubts:
-Wich values L1 & L2?
-I have only one 10H inductance & two caps 40uF mkp in oil, it's necessary other inductance same value 10H or wich value & order in the schematic?
-How can know best value for C4?
First of all thanks for support really appreciated, I have still several doubts:
-Wich values L1 & L2?
-I have only one 10H inductance & two caps 40uF mkp in oil, it's necessary other inductance same value 10H or wich value & order in the schematic?
-How can know best value for C4?
hi Felipe,
The L1 should be 5H or more. Your 10H will be perfect. If you use the Salas HV shunt, you can omit L2 and C2.
If you want to model the power supply - to find best C4 value, please try PSUD2:
PSUD2
Start with 1uF, and increase until you get the B+ you need. But 4.7uF max, if you have nice rectifier AZ1 !!
The L1 should be 5H or more. Your 10H will be perfect. If you use the Salas HV shunt, you can omit L2 and C2.
If you want to model the power supply - to find best C4 value, please try PSUD2:
PSUD2
Start with 1uF, and increase until you get the B+ you need. But 4.7uF max, if you have nice rectifier AZ1 !!
Thanks again Rod,
-That's a good new, yes I will use Salas HV reg so can save 2nd inductance (a lot of money)🙂
-About PSUD2 wich load I have to use to simulate the 26 + Salas reg.? PSUD2 don't have AZ1, there is other tube on the library to simulate?
-For your heaters to simulate the needed PSU wich load I have to use?
Cheers, Felipe
-That's a good new, yes I will use Salas HV reg so can save 2nd inductance (a lot of money)🙂
-About PSUD2 wich load I have to use to simulate the 26 + Salas reg.? PSUD2 don't have AZ1, there is other tube on the library to simulate?
-For your heaters to simulate the needed PSU wich load I have to use?
Cheers, Felipe
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Try another directly heated rectifier like 5R4.
For filament model, please use current source, 1.05A for load.
For filament model, please use current source, 1.05A for load.
hi Felipe,
if you remove the .txt from the filename, here is a PSUD2 file for 26 with 6V 50VA, and recommended support components.....
.
Sorry I don't understand you, I want to try battery bias, wich load value for 26+Salas reg & wich load value for heaters?
Can't open your file, how can do?
For the 26 B+ model, please use current load, 10mA (or change the 10mA to the operating point you have chosen).
For Filament, choose Constant Current load, value = 1.05A
to open PSU file, it must end in .PSU. You have to delete the .txt I put at the end, so I could post it.
Thank you Mike🙂
For my 26 I will use your pcb Salas HV reg😉
@Rod
Don't worry I opened Mike file
BTW wich voltage & current are you setting the Salas HV reg?
For my 26 I will use your pcb Salas HV reg😉
@Rod
Don't worry I opened Mike file
BTW wich voltage & current are you setting the Salas HV reg?
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Rod mentioned 5R4GY as rectifier, and this is a very good choice - what I use and better than all the GZ types. It will be sufficient for most SE 300b amps. for a preamp AZ1 mesh and 80 or 5Y3 (same, octal base) may be better still.
5R4GY has more voltage drop than others, but usefully is 2A.
Andy
5R4GY has more voltage drop than others, but usefully is 2A.
Andy
Thanks Andy, Rod suggested 5R4GY to simulate the AZ1 in the PSUD2
Are you using 138V for B+?
Felipe
For 6V trafo you can use 1N5821 or 1N5822. I think the -21 will give very slightly higher dc output.
OMG
Rod,
All I can say is Holy $hit!! The DHT board has made my amp using a 26 to drive my 2A3 DEAD QUIET. And preserved the sound of an AC heated triode. I think its time to tear apart my friends Welborne amps and rip out the poorly designed DC circuit on the 300B. It sounds lifeless so I suspect your board will perform like my #26.
The build was a piece of cake using that heat sink you recommended. I had to drill some holes in the sink since the holes were too large and use self tapping machine screws. be sure to clean and sand smooth the hole since it could short the transistor to sink.
Rod,
All I can say is Holy $hit!! The DHT board has made my amp using a 26 to drive my 2A3 DEAD QUIET. And preserved the sound of an AC heated triode. I think its time to tear apart my friends Welborne amps and rip out the poorly designed DC circuit on the 300B. It sounds lifeless so I suspect your board will perform like my #26.
The build was a piece of cake using that heat sink you recommended. I had to drill some holes in the sink since the holes were too large and use self tapping machine screws. be sure to clean and sand smooth the hole since it could short the transistor to sink.
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