I found a giant vacuum tube at a electronic store. Can I use it for a VTTC

[Fluffyboii]

Its a old radio amplifier tube. I wonder if I can use it for anything at all but It was so neat I couldnt stop myself from buying it. Hopefully I can use it for a tesla coil. Any ideas. Its Thomson-CSF TH 4T4100.

 

[KeepItSimpleStupid]

2kW transmit tube for < 30 MHz. Datasheet: https://frank.pocnet.net/sheets/132/t/TH4T4100.pdf

 

[unclejed613]

that's a pretty hefty filament supply you will be needing.... 12.6V@35A. 440W center tapped filament transformers are not a trivial piece of hardware...

 

[Fluffyboii]

that's a pretty hefty filament supply you will be needing.... 12.6V@35A. 440W center tapped filament transformers are not a trivial piece of hardware...

Can't I use my modified microwave transformer to feed the filament voltage. I got a full bridge rectifier rated for 1000w connetcted to it and It should have a 12 volt output.

 

[atferrari]

You should test it upfront.

/Edit
How much you paid?
Edit/

 

[atferrari]

that's a pretty hefty filament supply you will be needing.... 12.6V@35A. 440W center tapped filament transformers are not a trivial piece of hardware...

35A?

 

[Fluffyboii]

You should test it upfront.

/Edit
How much you paid?
Edit/

I paid around 36 dolars and got a simpson 260 multimeter (not tested) with it. And yeah 35A for filament is some serious stuff.

 

[ronsimpson]

The voltage on the filament is critical to a long life. Measure at the tube not at the power supply.

 

[ChrisP58]

Can't I use my modified microwave transformer to feed the filament voltage. I got a full bridge rectifier rated for 1000w connetcted to it and It should have a 12 volt output.

Is the bridge rectifier itself rated for 1000 Watts of power dissipation? Or is it that the product of the Amp Voltage rating is 1000 Watts? I'll assume the latter.

But the real question is what is it's rated current? It won't work for the filament supply if it's rated for 1 Amp @ 1000 Volts.

That said, do you really need a rectifier at all? The datasheet doesn't say that the filament needs DC. I've not worked with tubes much, but the few that I've looked at all used AC for the filament.

 

[Nigel Goodwin]

Is the bridge rectifier itself rated for 1000 Watts of power dissipation? Or is it that the product of the Amp Voltage rating is 1000 Watts? I'll assume the latter.

But the real question is what is it's rated current? It won't work for the filament supply if it's rated for 1 Amp @ 1000 Volts.

That said, do you really need a rectifier at all? The datasheet doesn't say that the filament needs DC. I've not worked with tubes much, but the few that I've looked at all used AC for the filament.

Makes no real difference, but AC was generally used as it's obviously simpler and cheaper - 'occasionally' DC would be used, so as to reduce any hum from the heater wiring.

One obvious use for DC heaters was the antique AC/DC radios etc. where if the mains was DC the heaters obviously ran off DC, but if the mains was AC then they got AC power instead. Funnily enough I've got an old HMV radio to look at currently - which uses U series valves, with 100mA series heaters.

 

[Fluffyboii]

Makes no real difference, but AC was generally used as it's obviously simpler and cheaper - 'occasionally' DC would be used, so as to reduce any hum from the heater wiring.

One obvious use for DC heaters was the antique AC/DC radios etc. where if the mains was DC the heaters obviously ran off DC, but if the mains was AC then they got AC power instead. Funnily enough I've got an old HMV radio to look at currently - which uses U series valves, with 100mA series heaters.

You are right, probably I dont need a rectifier. The problem with my microwave transformer is even I got 12 volts output It will drop alot when underload so Its impossible to get exact 12.6 volts. Can I use a pc power supply rated 35amps at 12 volt line, since I am not going to use this at full 2Kv power I assume the flament can run at little bit lower 12volt range or even 11.5volts or it must have that exact 12.6.

 

[Nigel Goodwin]

If you run at lower heater voltages valves run poorly, or not at all - as you're winding the transformer yourself, tweak the number of windings accordingly, so as to give the correct voltage when under load (which is how transformers are specified anyway).

 

[Fluffyboii]

If you run at lower heater voltages valves run poorly, or not at all - as you're winding the transformer yourself, tweak the number of windings accordingly, so as to give the correct voltage when under load (which is how transformers are specified anyway).

So it needs 12.6 volts under load, then the unloaded voltage may be a little bit higher ? I saw people using a resistor to slow start the flament do I need something like this and most importantly can I use this to power a tesla coil.

 

[Nigel Goodwin]

I've no idea about tesla coils, or what they require - but as far as I'm aware they don't usually use transmitter valves?. Bear in mind you would be wasting about 400W just on the heater.

 

[Fluffyboii]

I've no idea about tesla coils, or what they require - but as far as I'm aware they don't usually use transmitter valves?. Bear in mind you would be wasting about 400W just on the heater.

I dont know much about vacuum tubes. But I have seen some vacuum tube tesla coil designes. Is there any thing I can do with this except making a decoration item anyway.

 

[Nigel Goodwin]

I would have thought a nice decoration is probably the best use for it?.

Even for it's intended use it's too high a power for amateur radio use - and to honest, 400W wasted just on the heater is far too much in these energy efficient days.

 

[MaxHeadRoom78]

35A?

The H.F. heating equipment I used to work on used a huge transmitter valve/tube for the oscillator.
The cathode heater was 3kw. !!
Max.

 

[Fluffyboii]

I would have thought a nice decoration is probably the best use for it?.

Even for it's intended use it's too high a power for amateur radio use - and to honest, 400W wasted just on the heater is far too much in these energy efficient days.

They were selling little versions of this too. Maybe I should got one before messing with this bad boy.

 

[Nigel Goodwin]

The H.F. heating equipment I used to work on used a huge transmitter valve/tube for the oscillator.
The cathode heater was 3kw. !!
Max.

WOW

When I was at college the main teacher (Mr Oxley) used to go on about his time in radar during the war, and capacitors bigger than the classroom we were in.

 

[schmitt trigger]

Many years ago, I worked at a company which employed several induction heaters.

It used similar tubes like these, but from EIMAC. Don't recall the part number.

The heater on its own would glow as bright and white as large incandescent light bulb.

The anode's high voltage and high current made these tubes very dangerous. As a fact, the worst industrial accident I've personally witnessed involved one of these.