Audioromy M-828A FU29

This is my tube amp. Powerful, clean-sounding with stereo imaging to die for. Uses soviet military tubes, 110 mm high and 60 mm fat, like small Coke cans. 

Tech data:

  • Input Power 110V-240V  AVAILABLE
  • Output Power 30 W x 2  Class A
  • Output Tube FU29 x 2 (double tetrodes)
  • Driver Tube 6N2 x 2 , 6N1 x 2
  • Signal/Noise Ratio 90dB
  • Ohms 4 ohms 8 ohms
  • Input Consumption 160w
  • Frequency 20Hz-30KHz +/-1 dB
  • Distorsion Less than 0.5% at full power

Schematic form Audiokarma forum

FU29 tube

  • Cathode: indirectly heated, oxide-coated.
  • Envelope: glass, no-base.
  • Cooling: forced air.
  • Height: at most 110 mm.
  • Diameter: at most 61 mm.
  • Mass: at most 125 g.

FU29 Electrical Parameters

  • Heater voltage, 12.6 V
  • Heater current, 1-1.3 A
  • Anode current (at anode voltage 250 V, grid 1 voltage 11 V of first tetrode, grid 1 voltage 100 V of second tetrode, grid 2 voltage 175 V), mA 38-85
  • Interelectrode capacitance, input, at most 13-17 pF, output, at most 5-9 pF
  • transfer, at most 0.1
  • Output power, W, min:
  • 42W at anode voltage 400 V, grid 2 voltage at most 225 V, operating frequency 100-200 MHz 
  • 34W when over 500 h of service
  1. techandgadgets posted this