Z–Match & L-Match Tuners

Deluxe Z-Match

Most recent of the z-match tuners I’ve built. This one is in an LMB CR-442 with the blue half painted gray. Operation is 80 thru 10 meters .The front panel includes the tuning controls, tune/operate switch, capacitor add switch and the absorptive bridge visual SWR indicator LED. The bridge resistors are precision 50 Ohm 2W.

Views from top right: Front, Back, and Inside.
	The rear panel has the input and output BNCs, balanced line connectors, hi/low z selector switch and link ground switch for coax fed and long wire antennas. The schematic is shown below and uses z-match transformer designs developed by Charlie Lofgren, W6JJZ.

Compact Z-Match

Intended only for coax fed antennas, this one is built in a gray-painted Bud Mini Box. The tuning controls on the top are the same as the deluxe matcher above. The switch on the end above the antenna BNC selects the hi and low Z coupling links.

Views from top right, Front, Inside before toroid, Inside after toroid.
	Load resistors (under BNC) for the SWR bridge are 5 Watt thick-film units from Ohmite. These parts will handle maximum QRP power while tuning. The two inside views show the assembly before the toroid was installed and after. The toroid circuit is also a W6JJZ design.

NorCal BLT

NorCal’s BLT (Balanced Line Tuner) in the newer predrilled aluminum enclosure and painted gray. The BLT is also a W6JJZ design. The single-tuned toroid in the BLT will readily tune 40, 30 and 20 meters at QRP power levels. Higher frequency range is possible if the SWR is not sever. In combination with the Rock-Mite/20 I built in a BLT-size case, the pair makes a nice operating combo. Combo picture on Rock-Mite Page.

Shown above are the front controls: Coupling and antenna tuning, Tune/Operate switch and LED SWR indicator. Left on the back panel: Coax connectors, balanced line connectors, Z-link select switch and coax/long wire ground switch for the added option. Note: BLT replaced by BLTplus from Hendricks QRP Kits, qrpkits.com

BLTplus Modifications

Hendricks BLTplus (Balanced Line Tuner) in the newest and larger (4sq in.) prepunched enclosure including coax and longwire functions. The BLTplus continues with the basic W6JJZ design. Complete BLTplus details are on the qrpkits.com BLTplus webpage. Only modifications made to extend tuning range are included here.

Modifications include: • T106-6 Toroid • Switched 18-turn/14-turn tapped T2 pri. • Dual variable/fixed switched loading • Extended tuning range ... from 3 Ohms to 1.6 kOhms • Profiled using AI1H method (QEX Oct '03) See mods drawing for details BLTplus Mods — BLTplus Mods PDF Dwg.

W5USJ and BLT Z-Match Tuner Schematics

Visual SWR Bridge Schematics