I have a question about these micro tube mic ?
- Thread starter mic test
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Help Support GroupDIY Audio Forum:
The input stage is equipped with a carefully selected subminiature tube.
All voltages and currents necessary for operation are transferred via a transverter circuit
provided.
The low output impedance on the 3-pin XLR connector is via an OPV and the output
transformer realized.
can we try to make a circuit like this? do you have an ID? How do we get it onto a circuit board?
All voltages and currents necessary for operation are transferred via a transverter circuit
provided.
The low output impedance on the 3-pin XLR connector is via an OPV and the output
transformer realized.
can we try to make a circuit like this? do you have an ID? How do we get it onto a circuit board?
Last edited:
where can I find this 10 v zener? In the circuit diagram I have a circuit board like this here and I can also test the matching tubes
Hello, I know it's an old post, but what do you think of this board??? It might help polarize LDC, it's based on the shematic upper in the thread...would it be "easy" to implement it in the Frankebtube design??? Hex Inverter Voltage Multiplier for Condenser Microphones - Share Project - PCBWay. Today I build it to make OPA Alice microphone
If you take the VCC for the DC-DC board from the 10V point (Zener cathode) on the FrankenTube circuit, it can work. At 10V, the DC-DC board should provide about 60+ volts for capsule polarization.
Hello, I know it's an old post, but what do you think of this board??? It might help polarize LDC, it's based on the shematic upper in the thread...would it be "easy" to implement it in the Frankebtube design??? Hex Inverter Voltage Multiplier for Condenser Microphones - Share Project - PCBWay. Today I build it to make OPA Alice microphone
If you take the VCC for the DC-DC board from the 10V point (Zener cathode) on the FrankenTube circuit, it can work. At 10V, the DC-DC board should provide about 60+ volts for capsule polarization.
That particular one is a rectifier tube, but that's alright, as it's not connected either..
pasarski
Well-known member
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Not sure what you're trying to accomplish, but the capsule polarization voltage is probably not your biggest problem. Sure you need some kind of a voltage booster for that, but the biggest hurdle is to find a tube with low enough heater current draw, so you have something left for the rest of the circuit. This is the least current hungry tube I know. Probably almost impossible to find a good enough speciment for microphone use.
https://www.google.com/url?sa=t&sou...4QFnoECBUQAQ&usg=AOvVaw3W55O_EByPCXYWIi4nscr-
Where's the tube in the video??
Before you start building Frankentube make sure you have skills and everything necessary to solder those LM2665. Both POL and VCC points you marked are at ground. I also think you need to understand the Frankentube schematic, it is not a straightforward build. Many, if not most have failed.I also think it's a fake
pasarski
Well-known member
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- Jan 29, 2010
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Many tubes can work with that (I assume you still want to build a phantom powered tube mic?). Voltage is not the problem, current is. Phantom power is speced to provide 10mA IIUC. The tube I linked draws 10mA for the heater alone. You don't have anything left for the rest of the circuit unless you under heat it.Soldering is not the problem. First of all, finding a circuit that can work with 60-80 VDC
I'll keep trying, I find it really exciting
I found this in the links but the schematic link is offline
I finally finished the Phantom miniature tube DI. I got a MAX5033 DC-DC converter for heating supply after a bit of experimentation. Here is the final schematic: http://users.adelphia.net/~thomasholley/Guitar/Mini Tube DI.gif
As I do, I got carried away with "features" and additional switches for triode/pentode operation, a switch for transformer ratio adjustment to best suit these modes, and a floor lift. They work pretty well. I also added an unbalanced monitor.
The MAX5033 DC-DC converter is set to deliver 1.4 VDC at 20 mA output and draws approximately one milliamp on the input side. This is the lowest giveaway among several devices I've looked at. The output has a small residual switching noise using the component values derived from datasheet calculations. I added another small choke and a larger capacitor to the output, which successfully got rid of this residual noise.
I finally finished the Phantom miniature tube DI. I got a MAX5033 DC-DC converter for heating supply after a bit of experimentation. Here is the final schematic: http://users.adelphia.net/~thomasholley/Guitar/Mini Tube DI.gif
As I do, I got carried away with "features" and additional switches for triode/pentode operation, a switch for transformer ratio adjustment to best suit these modes, and a floor lift. They work pretty well. I also added an unbalanced monitor.
The MAX5033 DC-DC converter is set to deliver 1.4 VDC at 20 mA output and draws approximately one milliamp on the input side. This is the lowest giveaway among several devices I've looked at. The output has a small residual switching noise using the component values derived from datasheet calculations. I added another small choke and a larger capacitor to the output, which successfully got rid of this residual noise.
You can use Wayback Machine for
dead links:
https://web.archive.org/web/2006010...hia.net/~thomasholley/Guitar/Mini Tube DI.gif
dead links:
https://web.archive.org/web/2006010...hia.net/~thomasholley/Guitar/Mini Tube DI.gif
I think that circuit is more an idea than a real working thing - it wont work as advertized: If you e. g. activate ground lift, there is no power to the circuit.
