PA for DATV 2400 MHz OSCAR100
July / August 2019
After building high power RF amplifiers to be used for OSCAR-100 DATV for friends, i got the question:
“”can you make a complete PA for me as well””
First, I am a radio amateur, who likes to make equipment, I am not a factory, but I am willing to help other HAM’s because of the experience I gained over the years.
The PA’s I made are using the AMPLEON FET described in the http://www.f4vsg.com/?page_id=110 part of this site.
A nice description about these lineair amplifier could be found on that link.
The amplifier is build on a large copper block. The both sides are made from aluminium strip material. All solid mechanical parts are machined on a milling machine.
The BLC2425M10LS250Z fet is capable of over 250 Watt RF, but not a good idea for DATV-use to go to the limit !!
I am happy with a clean 100 Watt ++ output from the amplifier.
I also noticed that the PA when used on 2320 MHz SSB delivers over 100 Watt RF output !!
It gives a strong signal and in combination of a proper antenna signals in the higher Symbol-rate (SR) could be transmitted.
june 2020 info.
It is essential to mount the copper bottom-plate on a large heatsink using some thermal compound. A ventilator is a good idea to keep temperatures low.
At the input site there is a SMA connector for RF input.
Some 2 or 3 Watt input power is often OK to make the needed RF power-output. Please take care of a proper SWR on your antenna system.
There is a bias circuit inside the amplifier.
A diode protected voltage regulator is used to make the desired bias voltage in combination of some resistors, capacitors and a potentiometer to set the bias current. The PA is totally shielded after the top brass plate is mounted.
Important to have powerfull PA’s shielded against unwanted EMI / RFI .
After the first stock of ROGERS PCB’s are all used i ordered Goldplated ROGERS PCB’s
After mid of 2020 the new DATV Poweramplifiers are made using these Goldplated ROGERS PCB’s
Here an overview of measured specifications of a recent DATV Power amplifier.
March 13 2021 info:
The last years i assisted a lot of OM’s by helping them to have DATV power on 2400 MHz, tips and equipment.
I am always stimulating others to have activities on the SHF frequencies.
When OM’s see about the possibilities of using these frequencies there will be more OM’s active on these “”high””-frequencies !!
BUT for me it takes a lot of time to build/align and arrange all of this. I always asked a little more than all the buying costs. (and the risk for me destroying a component during mounting and testing and buying the new essential parts to fix it)
The last time i felt less happy not be able anymore to do my own projects.
So at the moment i have to say NO the new interested OM’s willing to have a HIGH POWER DATV AMPLIFIER.
10-2021 update:
Sorry to inform you that i am not capable anymore to build these HIGH-POWER DATV amplifiers for other OM’s.
I promised some OM’s to make them a high-power DATV amplifier. For these units i have the components and PCB. With some delay i will make and ship them. I am not starting up an order for new Duroid PCB’s
More technical info and user tips for this powerfull amplifier see here:
http://www.f4vsg.com/?page_id=110
fb 73
Robert
