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Active microcontroller Bias Supply Modul for vacuum tube amplifier PP push-pull

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For Sale:

Microcontroller output Tube bias control system, for Push-Pull Amplifiers.

Automatic dynamic bias control module (Bias Processor) for triode and pentode output stages push-pull (PP) amplifiers.



The Bias Processor dynamically controls automatic bias settings to maintain a strict symmetry of currents through both tube branches in the output stage, and to completely avoid flow of DC current through the output transformer, all with minimum requirements on anode current in the tubes. The DC saturates the output transformer which results in increased distortion of low-frequency sounds.

Bias control is realized by maintaining a constant bias on output tube grids, independently on the level of the driving signal.

The module may be supplied by the voltage for tube heating (6.3V AC) in the amplifier. An independent 6-9V AC power supply may also be used.

Bias Processor for PushPull amplifier specifications

No need to constantly re-adjust tube operating points
Significantly extended tube life due to smooth current supply
Current regulation not influenced by music signal
Undistorted sound for a great listening experience
Significant increase in signal clarity – extreme reduction of hum and noise level of the amplifier
No maintenance or additional setup needed
Safe operation due to minimized danger of runaway tube current
Setup cathode current and cathode resistors using a computer application
Connnecting to PC via USB
Visualisation of cathode current changes in real time in application
Full digital control with ARM Cortex M0 48MHz
4 ADC with 12-bit precision for measuring cathode current for each tube
4 DAC with 16-bit precision for each tube
Regulation of cathode current of the tubes from 1mA to 200mA
Setup any nominal cathode resistors from 1.0 Ohm to 10.0 Ohm with the step 0.1 Ohm for each tube
Noise reduction from 9-Pole Low-Pass filter output voltage for each tube , resulting clearer high-frequency tones
Slow ramp up of current over a further 60 s – 200 s
Changeable turn on delay time from 1 to 300 second
Their use is strongly recommended in existing amplifiers with fixed bias of output tube control grids, as aging of the tubes causes the need for a constant re-adjustment of their operating points.

200$ plus shipping for board bias control system + software + USB converter. Paypal please.

I Will shipping Worldwide.

Assistance in connecting and configuring. Via email.
 
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Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.