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Does this 1.2 KW amp from china look right?
- Thread starter USXDriver
- Start date
Likely this, but does not come with output transistors or heatsink.
Pardon Our Interruption...
www.ebay.ca
It looks like its designed around this mosfet.
1.2 KWT RF POWER AMPLIFIER ON 4 x SD4933 HAM RADIO HF/VHF/UHF RF power | eBay
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This is the mosfet that board is designed around.
It's a 50v device with a minimum of 40v. That's where they got the 1200 watt rating from in the add.
At 40v it's rated at 300 watts per device, and at 50v it's rated at 400 watts per device.
It's a 50v device with a minimum of 40v. That's where they got the 1200 watt rating from in the add.
At 40v it's rated at 300 watts per device, and at 50v it's rated at 400 watts per device.
The caulk or Hot Glue mess really shows the cra(ph)manship of the enslaved workers...
You know the mounting flanges on that thing for the "pills" still need to be mounted right?
If it's rated at 1.2kW - you'll need a fire extinguisher - there are not many ferrites, nor boards that can flow out that heat efficiently in that type of package.
You're not serious are you?
Pulse mode of 50% or less on time maybe - but --- WOOF
You know the mounting flanges on that thing for the "pills" still need to be mounted right?
You're not serious are you?
Pulse mode of 50% or less on time maybe - but --- WOOF
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Actually it needs a copper heat spreader. Aluminum has too much thermal resistance per square inch for a 300-Watt transistor that size. Copper, however, will absorb more heat per square inch. The much-larger surface of the spreader plate against the aluminum heat sink surface will carry the heat to the aluminum heat sink.
Most any RF power transistor rated over 150 Watts requires a heat spreader.
73
Most any RF power transistor rated over 150 Watts requires a heat spreader.
73
Seems to me the technical description for a "bare bones" amplifier with no relay or switching circuits is a "palett".
Still requires the antenna relay, bias switching, input attenuator (probably) and RF sensing circuit if you don't plan to key it with a patch cord like a ham linear.
Not so much a linear as a project element.
73
Still requires the antenna relay, bias switching, input attenuator (probably) and RF sensing circuit if you don't plan to key it with a patch cord like a ham linear.
Not so much a linear as a project element.
73
You will want the input attenuator, you really don't want to overdrive those devices.
Someone will want to drive it to get mo power not understanding that they need very little drive to get the rated output.
73
Jeff
And for those who are thinking about building one the copper board runs about
$80.00 to do it right......But they do work well.