High SWR shutdown - Requires optional RF power meter

Reflected Power reads in peak and average modes.

Faster responding meters.

More stable HV metering.

T/R relay sequencing. A built in sequence has been added that delays the bias relay by 20 ms with switching to TX. When switching back to RX the bias relay is immediately dropped and the coax relay is delayed by 20 ms. Sequencing may be disabled via. an internal jumper.

Sequenced output, an output signal from the sequence is also available to control devices such as transceiver TX inhibit or transverter switching.

The GND to TX circuit (PTT) has been redesigned for lower switching impedance to eliminate false TX trips on shared PTT lines.

Resettable fuses added in the relay power lines

Resettable fuse in the B- line replaces glass fuse.

Improved neutralization on the LA-22A and LA-12A. Provides even more stable operation and improves DC plate efficiency by 2% to 5%.

Low Q, T match input circuits on the LA-22A and LA-12A reduce drive power. Typical drive for 1500w output is 35 W for a LA-22A and 40 W for a LA-12A (3CPX800A7 tubes with 2,600 VDC full load plate voltage)

Plate Current Meter can be configured to read in peak more. Useful for low duty cycle modes such as pulse and SSB voice. Requires configuring internal jumpers and meter calibration.

Optional Dual Speed Blower, automatically slows the blower during receive & standby to lower blower noise and reduces operator fatigue.

Optional Air Pressure Switch, prevents operation if cooling air is not present.

Optional type SC or 7.16 DIN RF output connectors

Optional remote monitoring and control interface.

Optional Heater Relaxation circuit for the LA-72A. This option reduces the heater voltage during transmit to compensate for cathode back heating which occurs at UHF frequencies. This option is designed for operating modes that have key down continuous carrier output for more than 10 seconds at a time, such as digital modes (PSK-443, JT-65, etc.), FM, ATV and similar modes.