RF Power Grid Tubes · Triodes
GU-78B Russian HF Triode
Russian transmitting triode with 5 kW plate dissipation, designed for HF broadcast and long-distance shortwave communication systems.
- Plate Dissipation
- 5000 W
- Max Frequency
- 50 MHz
- Max Plate Voltage
- 7.0 kV
- Max Plate Current
- 1.5 A
About the GU-78B
The GU-78B is a power triode manufactured by Reflector. Russian transmitting triode with 5 kW plate dissipation, designed for HF broadcast and long-distance shortwave communication systems.
Key ratings of the GU-78B include tube type Triode, plate dissipation 5000 W, max plate voltage 7.0 kV, max plate current 1.5 A, mu 40 and max frequency 50 MHz.
Typical applications are HF shortwave broadcast, long-range military HF communications and medium-wave AM transmitters. Notable features: 5 kW plate dissipation, water-cooled HF triode, russian military-grade and 50 MHz optimized.
Power triodes are three-electrode grid tubes used as RF oscillators and amplifiers in industrial RF heating (plastic welding, induction heating, drying), RF-excited CO₂ lasers, broadcast transmitters and particle accelerators. In oscillator service they work with vacuum capacitors in the tank and matching circuits.
PartnerTubes supplies the GU-78B worldwide from Groningen, the Netherlands — availability, lead time and price are confirmed per enquiry. Our team can help with equivalent and cross-reference types, sockets and accessories, and supply programmes for OEM and maintenance customers. Interchangeability must always be confirmed for the specific equipment.
Technical specifications
| Tube Type | Triode |
|---|---|
| Plate Dissipation | 5000 W |
| Max Plate Voltage | 7.0 kV |
| Max Plate Current | 1.5 A |
| Mu | 40 |
| Max Frequency | 50 MHz |
| Filament Voltage | 20 V |
| Filament Current | 17 A |
| Cooling | Water |
Specifications are indicative and based on published manufacturer data. Always verify against the official datasheet and confirm suitability for your application before ordering.
Applications & features
Used in
- HF shortwave broadcast
- Long-range military HF communications
- Medium-wave AM transmitters
Key features
- 5 kW plate dissipation
- Water-cooled HF triode
- Russian military-grade
- 50 MHz optimized
Related parts & equivalents
Recommended alongside or as alternatives to the GU-78B.
Similar RF Power Grid Tubes
Comparable type, ratings, manufacturer or applications.
Vacuum capacitors for tank & matching circuits
Often ordered with the GU-78B for the same system.
Jennings UCSL 15–100 pF Variable Vacuum Capacitor 20 kV
Jennings Technology (CPI)
Jennings UCSL 25–200 pF Variable Vacuum Capacitor 25 kV
Jennings Technology (CPI)
Frequently asked questions
What is the GU-78B?
The GU-78B is a power triode manufactured by Reflector. Russian transmitting triode with 5 kW plate dissipation, designed for HF broadcast and long-distance shortwave communication systems.
What are the specifications of the GU-78B?
Tube Type: Triode; Plate Dissipation: 5000 W; Max Plate Voltage: 7.0 kV; Max Plate Current: 1.5 A; Mu: 40; Max Frequency: 50 MHz; Filament Voltage: 20 V; Filament Current: 17 A; Cooling: Water.
What is the GU-78B used for?
The GU-78B is used in HF shortwave broadcast, long-range military HF communications and medium-wave AM transmitters.
What are alternatives or related parts to the GU-78B?
Related and comparable parts include GU-84B, GU-43B, 3CX5000A7, 3CX15000A7, 3CX30000H7 and 3CX10000H3. Contact PartnerTubes to confirm interchangeability for your equipment.
Where can I buy the GU-78B?
The GU-78B is available from PartnerTubes (Grunius BV, Groningen, Netherlands) with worldwide shipping. Availability and lead time are confirmed on request. Request a quote at https://www.partnertubes.com/contact/?part=GU-78B or email info@partnertubes.com.