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THE AM BULLETIN BOARD => Technical Forum => Topic started by: John K5PRO on July 18, 2010, 02:44:57 AM



Title: 2 kW transistors
Post by: John K5PRO on July 18, 2010, 02:44:57 AM
Silicon Carbide FETs from Microsemi can produce about 2 kW pulsed at 15% duty factor at 200 Mhz now. Vdd is > 100 VDC. Finally something that can replace a tube with respectable Pout.


Title: Re: 2 kW transistors
Post by: KF1Z on July 18, 2010, 07:28:27 AM
What's the price tag?


Title: Re: 2 kW transistors
Post by: KM1H on July 18, 2010, 10:10:11 AM
If you have to ask you cant afford them :o


Title: Re: 2 kW transistors
Post by: KF1Z on July 18, 2010, 10:14:19 AM
That's the point exactly....

Fets that handle 1 to 2kw are nothing too new, they've been around a few years.

But most of them cost over $1k each

Not exactly "experimenter's devices"

 ;)


Title: Re: 2 kW transistors
Post by: W1ATR on July 18, 2010, 10:23:06 AM
That's the point exactly....

Fets that handle 1 to 2kw are nothing too new, they've been around a few years.

But most of them cost over $1k each

Not exactly "experimenter's devices"

 ;)


Right, and a slight mistake in the circuit buildup and those nice little kilobuck doodads let off a flash like a Romulun disrupter haha.

Buck a watt for a delicate fet or 40 cents a watt for a durable toob. hmmmm (20 cents a watt on the bigger toobs)


Title: Re: 2 kW transistors
Post by: Pete, WA2CWA on July 18, 2010, 04:33:46 PM
VHF and UHF devices ~ price around $1400 each in single lot quantities.


Title: Re: 2 kW transistors
Post by: John K5PRO on July 19, 2010, 02:07:46 AM
Correct, price is less than 2 kilobucks per device. All the new kW level devices so far are 50 V LDMOS parts, these are 120 Volt wide bandgap devices, so they run high temperatures and matching is quite simple. Since we are building a 5 kW brick at work, then going to make a 25 kW unit, this is quite cheap, compared to trying to combine many lower power devices.

I doubt us hams could afford it, but these are the bellweather of things to come. I reckon that thermionic devices under a kW will eventually be rare except for the seemingly plentiful supply of NOS glass tubes like 813s and 6146.
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