Description
The BW1185J2F / YD1212 is a water cooled power triode of coaxial ceramic-metal construction. It is intended primarily for industrial RF heating machines. It has an integral water jacket.
Electrical Characteristics of BW1185J2F / YD1212
Filament: Thoriated Tungsten
Filament voltage (see note 1): 12.6 V
Filament current: 380 A
Surge filament current (peak) (see note 2): 2000 A max
Filament cold resistance: 3.6 mΩ
Peak usable cathode current: 175 A
Amplification factor (Va = 14 kV, Ia = 10 A): 40
Mutual conductance (Va = 14 kV, Ia = 10 A): 190 mA/V
Inter – electrode capacitances:
Grid to anode: 60 pF
Grid to filament: 185 pF
Anode to filament: 3.0 pF
Mechanical Characteristics of BW1185J2F / YD1212
Overall length (Excluding leads): 446.00 mm (17.560 inches) max
Overall diameter: 190.5 mm (7.500 inches) max
Net weight: 15.6 kg (34.4 pounds) approx
Mounting position (see note 3): Vertical, anode up or down
Accessories of BW1185J2F / YD1212
Water coupling (2 supplied with tube): MA709B
Water union, 25 mm hose (optional): MA2654A
Filament connector (with lead): MA475A
Filament connector (without lead): MA291C
Filament/cathode connector (with lead): MA475B
Filament/cathode connector (without lead): MA291D
For frequencies above 2 MHz, cathode connector MA291F should be used in conjunction with a strip connection to provide a low inductance cathode return
Grid connector: MA342
Thermal fuse: MA85G
The tightening torque applied to the clamping screw must be between the limits of 20 lb.in (0.231 kg.m) min, 35 lb.in (0.404 kg.m) max.
Cooling
The BW1185J2F / YD1212 has an integral water jacket. The water cooling requirements are given in the following table.
| Anode + Grid Dissipation (kW) | Inlet Temperature (°C) | Minimum Rate of Water Flow (l/min) | Minimum Rate of Water Flow (imp.gal/min) | Inlet Pressure (atm) | Outlet Temperature (°C) |
|---|---|---|---|---|---|
| 120 | 20 | 60 | 13.2 | 0.7 | 50 |
| 120 | 50 | 90 | 19.8 | 1.3 | 70 |
| 80 | 20 | 34 | 7.5 | 0.3 | 55 |
| 80 | 50 | 54 | 11.9 | 0.55 | 72 |
| 40 | 20 | 15 | 3.3 | 0.07 | 62 |
| 40 | 50 | 24 | 5.3 | 0.13 | 76 |
The inlet water temperature must never exceed 50 ⁰C. The water pressure must never exceed 600 kPa(87 lb/in2).
The temperature of the seals and envelope must not exceed 200 ⁰C. Cooling of the seals by low velocity air flow or water cooled filament connectors is required.
Radio Frequency Oscillator For Industrial Service
(Class C conditions, one tube)
Maximum Ratings (Absolute values) of BW1185J2F / YD1212
Frequency: 30 MHz
Anode voltage: 16.8 kV max
Anode input power: 375 kW max
Anode dissipation: 120 kW max
Grid voltage (negative value): 2.0 kV max
Grid current:
On load: 7.0 A max
Off load: 8.5 A max
Grid dissipation: 3.0 kW max
Grid circuit resistance: 10 kΩ max
Cathode current: 31 A max
Typical Operating Conditions of BW1185J2F / YD1212
| Parameter | 30 MHz | 30 MHz | 30 MHz | Unit | ||
|---|---|---|---|---|---|---|
| Frequency | 30 | 30 | 30 | MHz | ||
| Anode voltage | 10 | 12 | 14 | kV | ||
| Anode current | 23.6 | 24.7 | 23.5 | A | ||
| Anode dissipation | 56.6 | 67.4 | 81.5 | kW | ||
| Grid voltage | -580 | -695 | -810 | V | ||
| Grid resistor | 87 | 108 | 135 | Ω | ||
| Grid current, on load | 6.7 | 6.4 | 6.0 | A | ||
| Grid current, off load | 8.4 | 8.0 | 8.0 | A | ||
| Grid dissipation | 2.6 | 2.6 | 2.6 | kW | ||
| Feedback ratio | 9.1 | 10.5 | 11 | % | ||
| Drive power | 6.4 | 7.1 | 7.5 | kW | ||
| Output power | 179.4 | 229.3 | 247.5 | kW | ||
| Efficiency | 76.0 | 77.3 | 75.2 | % | ||
| Oscillator output power (See note 5) | 173.0 | 222.2 | 240 | kW |
NOTES
1. Temporary fluctuations up to +5% or -10% in filament voltage are permissible.
2. The filament current of BW1185J2F / YD1212 must not exceed 2000 A, even momentarily, at any time.
3. If the tube is mounted with the anode uppermost, the water inlet and outlet connections should be reversed (see outline).
4. The feedback ratio is defined as Vg(pk) × 100 / Va(pk), where Vg(pk) = peak R.F. grid voltage in volts and Va(pk) = peak R.F. anode voltage in volts.
5. Oscillator output power = Pout – Pdrive, where Pout = output power of tube to anode circuit and Pdrive = drive power fed back to grid circuit.
