What if implement grid choke with central tap I have on hand. Does it provide any benefit for given LTP with ccs in place of 470k resistors here?
I am not sure that I understand what you want to do.
Do you want to use a choke to substitute for those 470k resistors?
I do not think there is any choke in the world that has 470k impedance from 20Hz to 20kHz.
Or, please explain what it is that you want to do.
I used a 5H choke to function as a CCS to a pair of very high transconductance 6C45pi triodes, that made it a phase splitter.
Worked great. And it did not need a negative supply for the 5H "CCS".
A 12AX7 is not a good choice for a Choke CCS.
The 12AX7 has too little bias voltage, and the 12AX7 has low transconductance, so it needs an extremely high impedance CCS, that a choke can not provide from 20Hz to 20kHz.
I have used a 12AY7 and an LM334 to make a phase splitter.
I also used a 12AU7 and an LM334 to make a phase splitter.
I will be investigating using an E88CC and an LM334 to make a phase splitter.
I do not want to have to build a negative supply for the LM334, so I will try using a 6V battery and just replace it once a month.
Do you want to use a choke to substitute for those 470k resistors?
I do not think there is any choke in the world that has 470k impedance from 20Hz to 20kHz.
Or, please explain what it is that you want to do.
I used a 5H choke to function as a CCS to a pair of very high transconductance 6C45pi triodes, that made it a phase splitter.
Worked great. And it did not need a negative supply for the 5H "CCS".
A 12AX7 is not a good choice for a Choke CCS.
The 12AX7 has too little bias voltage, and the 12AX7 has low transconductance, so it needs an extremely high impedance CCS, that a choke can not provide from 20Hz to 20kHz.
I have used a 12AY7 and an LM334 to make a phase splitter.
I also used a 12AU7 and an LM334 to make a phase splitter.
I will be investigating using an E88CC and an LM334 to make a phase splitter.
I do not want to have to build a negative supply for the LM334, so I will try using a 6V battery and just replace it once a month.
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thank you, the scheme provided for example, it's very much like mine, but i have E180CC tube. Choke I have is from Silk it has 7000H (cant measure, just believe him) so has plenty of impedance on 20HZ and upwards. It is not to substitute pentode in this case, it is to ground the grids of double triode, center tap is going to the ground.
If one end of the choke goes to one triode grid, and the center tap of the choke goes to ground,
then where does the other end of the choke connect to?
The choke is 7000H.
But ask the manufacturer of the choke, what is the distributed capacitance from one end of the choke to the other end of the choke.
Too much capacitance will tend short out the signal at high frequencies.
then where does the other end of the choke connect to?
The choke is 7000H.
But ask the manufacturer of the choke, what is the distributed capacitance from one end of the choke to the other end of the choke.
Too much capacitance will tend short out the signal at high frequencies.
I guess I was correct about the connections of the choke. The third connection goes to the other grid.
When you get the choke, and install it, it will be very interesting to see what a 10kHz square wave applied to the input looks like.
Note: it is not fair to use a 50 Ohm or 600 Ohm square wave generator and connect it directly to your input connector.
Instead, connect a series resistor from the 50 or 600 Ohm output to the input connector.
The resistance of that resistor? Set it equal to the Output Impedance of the various signal source that will drive that center tapped choke.
Tube preamp; Solid state preamp, CD player, Phono preamp, Tube FM tuner, Solid State FM tuner, etc.
Each of those will have different output impedances, so to test the choke input, you need to use a variety of resistances in series with the 50 or 600 Ohm square wave generator.
I used to use interstage transformers of various manufacturers, and even used a center tapped choke too.
I no longer have signal paths that use interstage and/or center tapped chokes.
Just my preferences.
Have fun!
I am sure everybody reading this thread would like to see the rest of your amplifier schematic.
When you get the choke, and install it, it will be very interesting to see what a 10kHz square wave applied to the input looks like.
Note: it is not fair to use a 50 Ohm or 600 Ohm square wave generator and connect it directly to your input connector.
Instead, connect a series resistor from the 50 or 600 Ohm output to the input connector.
The resistance of that resistor? Set it equal to the Output Impedance of the various signal source that will drive that center tapped choke.
Tube preamp; Solid state preamp, CD player, Phono preamp, Tube FM tuner, Solid State FM tuner, etc.
Each of those will have different output impedances, so to test the choke input, you need to use a variety of resistances in series with the 50 or 600 Ohm square wave generator.
I used to use interstage transformers of various manufacturers, and even used a center tapped choke too.
I no longer have signal paths that use interstage and/or center tapped chokes.
Just my preferences.
Have fun!
I am sure everybody reading this thread would like to see the rest of your amplifier schematic.