RFT18-20 | EFHW Matching Transformer | 20W

This is a high efficiency matching transformer, ultraportable, for SOTA or other outdoor activities and not only. Based on a FaiRite larger size ferrite bead instead of a toroidal core ( NOT the FT82-43 or similar!) it has excellent thermal behaviour and efficiency, > 85…90% (@3.6MHz). Enclosure design copyright Luis – CT2FZI. Technical description file available below at “Downloads”.

Enclosure color: grey or black

Manufacturer code: ROW-RFT18-20

Ordering code: RFT18-20

Applications: for 1/2 wire (EFHW antennas, QRP, SOTA, portable etc.)

Fast deployment antenna wire length: ~ 9.35m (30.5ft) for 20m band (EU QRP region, 14.285KHz), min. 5..7m above ground

Antena wire length: ~40m for 80-10m operation, use min. 20m of wire for decent results

Transformation ratio: impedance tarsnformation 1:49 (autotransformer, 3 + 21 turns, turns ratio 1:7)

Compensation capacitor: 100pF Silver Mica, 300Vdc inside

Power handling: 20W and more (120s @ CW – core temp. is 25°C, on dummy load)

Ferrite Bead Material: 43

Frequency range: 3- 30MHz

Transformer Efficiency: > 85…90% @ 3.6MHz

RF max. power depends on application: 20W CW

VSWR: < 2 with 3200Ω load (please see Datasheet below)

Weight: 35g

Dimmensions: 8.8cm x 2.6cm x 2.6 cm