EMRFD Message Archive 1642

Message Date From Subject
1642 2008-05-13 10:19:56 michael taylor RF power transistors from ST
I was wondering if anyone has used some the LDMOS RF FETs from ST
Microelectronics, such as the PD55003-E (3W 500MHz 12Vdd PG=17db)
which is a gull-wing surface mount device, that should be large enough
to easily homebrew with. I was wondering if I was missing anything
obvious that makes them less desirable, or if anyone had any
experience building an QRP RF amp (HF or VHF+) with them.

ST PD55003-E

Michael, VE3TIX
1643 2008-05-13 11:22:43 Graham Re: RF power transistors from ST

It depends on the frequency you intend to use them at.
Probably a good choice at VHF/UHF.

If you were going to use them at HF, I would choose a
transistor designed for HF, with less gain at UHF to get
you into stability problems.

STM has many HF parts.

You might also want to consider the Mitsubishi RD series parts at
HF, that come in TO-220 packages and SOT-89. I have personally
used them in multiple RF-PA designs, and they are easy to use
and very well behaved.