close up picture of the MRFE6VP61K25H 144 MHz prototype.
PCB
size is 12 cm x 7.3 cm
Typical measurement
IMD performances
at 800W PEP
Youtube
video of the amplifer running at 50V 2.5A Idq
Youtube
video of the amplifer running at 44V low Idq (for non linear mode) Board is
black coated for accurate temperature measurement
More
information are available in DUBUS Q4 / 2010.
Article present one of my latest design with the MRFE6VP61K25H from
Freescale semiconductor, this new unmatched LDMOS transistor allow
design from 1.8 MHz to 600 MHz,
This amplifier can be operated in linear (SSB) operation or class C
(CW/ FSK / JT ) for improved efficiency.
Errata from dubus article,
- PCB supplier is not Taconic
but Arlon, TC350 reference is correct.
- Fig 10 is IMD at 400W , Fig
11 is IMD at 200W (could be read on spectrum screen)
Find detail about the copper heatspreader here,
note that is was done for originaly done for US (4/40) screws,
Also mechanical side is very important in this design, you need to
respect recommendation about mounting surface requirement:
flatness need to be 0.4mils/inch or better
also Freescale recommends the criteria of average
roughness (Ra) of 32 micron-inches
Next to come: HF amplifier ! prototype working, be patient for publication ...
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BEKO
use also the new MRFE6VP61K25H in it's brand new HLV1000 &
HLV2000.
Very good design and integration from Bernhard ! very
compact full amplifier including supply and all protections
RFHAM Passive
component kit & transistor for building this amplifier,
Lucien F1TE has designed very great
control & security boards around the amplifier
These boards have been sucessfully tested on MRF6VP11KH (earlier
version of the design with lower power)
Tags: MRFE6VP61K25H, LDMOS,
F1JRD, Solid state amplifier, Freescale, Rugged transistor, Gain, High
efficiency, MRF154, MRF157,HF amplifier, Ham radio,