2-4W VHF Linear PA suggestions

[vu2tve]

Hi,

I need to build a driver stage that will sit between a LimeSDR and a MRF101AN based final output stage.

I'm shooting for about 16-18 dB of gain, and a final output power of 33-35dBm.

Any suggestions where I can look for to begin design? I'm not averse to building PCB's if there are good reference designs available. I'm looking specifically at the FM Band of 88-108MHz

P.S. I know that the drive needed by the MRF101AN is just 1W. However, I would like to have some legroom so having a max output power of 2-3W is desirable. I can tweak the signal power from the LimeSDR to get the right output power.

Thanks!

[David Hess]

Other than cost, why not cascade two MRF101AN stages?

[M0HZH]

LimeSDR will require some output filtering before amplifying.

RD06HVF1 is commonly used for HF/VHF and will fit the bill on gain and output power; it runs at a lower voltage (13.5V typically) than the MRF101 stage and there is an official application note for 175MHz that could be adapted:

https://www.mitsubishielectric-mesh.com/products/pdf/rd06hvf1.pdf

There are 88-108MHz designs out there that use it, it's worth looking around.

[vu2tve]

I was just thinking that myself!! Thanks for nudging me further. I have an MRF101AN on hand and am going to build another PCB for it.

Also, I contact NXP and they recommended these two active part numbers - MW6S004N and AFIC901N.

Thanks!

[vu2tve]

Yeah. I can see some ebay sellers selling this part.

Long ago, I had purchased a "15 Watt FM amplifier" from aliexpress that used RD15HVF1, and after much headache, it turned out that the transistor was a dud

So I'm thinking I'll order a couple of RD06HVF to experiment with, but possible go with active part numbers sold through mouser/digikey etc, so that I don't run the risk of getting a dud.

[vu2tve]

Also, I see this part number being mentioned a bit too - rqa0009 (does not seem to be an active part, except being found on ebay)

wonder if there is some experience in the community here with this (https://aliot.com.ua/pdf/rqa0009.pdf)