Pride Amp Series, Руководство по обслуживанию

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Pride DX300 CHAPTER 4
4.6 Tube Replacement:
If a tube failure does occur, a likely reason for this would be a loss of one or more
of the required operating voltages at the tube socket. Thus, before a tube is
replaced, the voltage measurement procedure should be followed to determine if
further repairs are necessary. If all required voltages are present, the tube can then
be replaced safely.
The 4CX250R is a 'ruggedized' 4CX250B with a better cathode and more gain. It is
pin and heater compatible with the 250B. The Eimac catalogue says: "The
4CX250R/7580W will replace the 4CX250B in equipment where the range of bias
adjustment will tolerate this higher perveance tube and where the tuning range can
compensate for the small differences in input and output capacitances. It means
you may need a bit more negative G1 bias to set the required standing current
(100mA per tube).
Brand of tube types that work in the DX300
Eimac
Best
Taylor Very Good
Svetlanta (Russian) Very Good
Edcom Not Good
Tubes that will work
4CX250B, 4CX250R,
Have heard of people using a 4CX350B but I haven’t tested that.
4CX250B/7203 4CX250R/7580W
Characteristics
Plate Dissipation (Max.) 250 Watts
Screen Dissipation (Max.) 12 Watts
Grid Dissipation (Max.) 2 Watts
Frequency for Max. rating (CW) 500 MHz
Amplification Factor 5
Filament/Cathode Oxide Coated
Voltage 6.0 Volts
Current 2.6 Amps
Capacitance Grounded Cathode
Input 4.5 pf
Output .04 pf
Feedthrough 15.7 pf
Capacitance Grounded Grid
Input 4.5 pf
Output .01 pf
Feedthrough 13.0 pf
Cooling Forced Air
Base 9 Pin Special
Air Socket SK-600A
Air Chimney SK-606
Boiler ---
Length 2.46 in; 62.50 mm
Diameter 1.64 in; 41.70 mm
Weight 4 oz; 113 gm
Characteristics
Plate Dissipation (Max.) 250 Watts
Screen Dissipation (Max.) 12 Watts
Grid Dissipation (Max.) 2 Watts
Frequency for Max. rating (CW) 500 MHz
Amplification Factor 5
Filament/Cathode Oxide Coated
Voltage 6.0 Volts
Current 2.6 Amps
Capacitance Grounded Cathode
Input 4.8 pf
Output .04 pf
Feedthrough 17.5 pf
Capacitance Grounded Grid
Input --- pf
Output --- pf
Feedthrough --- pf
Cooling Forced Air
Base 9 Pin Special
Air Socket SK-600A
Air Chimney SK-606
Boiler ---
Length 2.46 in; 62.50 mm
Diameter 1.64 in; 41.70 mm
Weight 4 oz; 113 gm