7kW tube

[Se7en]

what this all about:

7kW Linear SSB up to 70 MHz.
Filament voltage: 6,3V

Filament current: 57-67A

Anode voltage: 3.0-6.0kV

Grid2 voltage: 0.9kV

Mutual conductance: 36-44mA/V

Height: 260 mm
Diameter: at most 124 mm
Mass: at most 3,5 kg
Tetrode GU-47B (7kW Linear SSB up to 70 MHz !) New | eBay​

 

[AudioShockwav]

It is a tube....and if you have all the rest of the parts needed you could build a nice amp with it.

73
Jeff

 

[Se7en]

It is a tube....and if you have all the rest of the parts needed you could build a nice amp with it.

73
Jeff

any reason why some say to stay away from "Russian made tubes" ?

 

[Needle Bender]

there build quality is inconsistant

 

[BJ radionut]

Make a nice driver!
If you could afford to run the final...
All the best
BJ

 

[Needle Bender]

Make a nice driver!
If you could afford to run the final...
All the best
BJ

no sh*t. only 8-12db gain for 4kw. you need between 250w and 650w drive. thats crappy for a tetrode. id go with a 4-1000. in grounded grid 175w in will drive it to 3500wpep or screen driving it 30w will get 3500 out

 

[Se7en]

no sh*t. only 8-12db gain for 4kw. you need between 250w and 650w drive. thats crappy for a tetrode. id go with a 4-1000. in grounded grid 175w in will drive it to 3500wpep or screen driving it 30w will get 3500 out

i totally agree on the single 4-1k -> http://rover.ebay.com/rover/1/711-5...0001&campid=5336136228&icep_item=130566549732 @ that price btter off just buying a collins 30s

 

[wavrider]

no sh*t. only 8-12db gain for 4kw. you need between 250w and 650w drive. thats crappy for a tetrode. id go with a 4-1000. in grounded grid 175w in will drive it to 3500wpep or screen driving it 30w will get 3500 out

Got a home brew sitting in the shack 5700 vdc on top of that big bottle, sure warms the shack up and makes that watt meter know it is getting a work out. 75 watts of drive will make a 2kw watt meter cry.

 

[Needle Bender]

Got a home brew sitting in the shack 5700 vdc on top of that big bottle, sure warms the shack up and makes that watt meter know it is getting a work out. 75 watts of drive will make a 2kw watt meter cry.

is that 5700v under load or at idle? what amount of plate current under full load?

 

[522]

I like the
$89.50
Standard Shipping​

 

[wavrider]

is that 5700v under load or at idle? what amount of plate current under full load?

At idle. drops to around 5400 under load, 75 watts drive .6ma PI, over 2KW carrier output. Tube is just loafing at that drive level, PS rated at 1.5 amp CCS.

I built it just to build one using a 4x1, tested it, worked it on 75 meters and 20 meters for a few weeks. Then rolled it into a corner and there it sits.

 

[Crusher]

I don't know about tetrode tubes, but the russian triodes need biasing. Most like using the zero bias triodes so that no biasing is required. If they are not biased, the will draw heavy anode current and fail shortly after.

 

[wavrider]

Some 4X1 amp schematics I have seen use Zero bias I prefer a zener in the circuit, keep the idle current lower. Think I put a 7.5V 50 watt in that circuit.

 

[nomade]

Two GU-47B by UY7MM.
Power output: 10 kW
Power supply: 380 V
Driver Power: 200 W

 

[wavrider]

Welcome to the Forum, thanks for the pictures.