The ARB-704 will replace the current series of amplifier interface buffers(702I, 702I2, 702K, 702Y). The ARB-704 will work with almost any transceiver without the need for a plug-and-play cable.

The ARB-704 advanced interface is compatible with all common radios and amplifiers even though radios and amplifiers do not have standardized voltages, accessory plugs, or wiring. This interface is designed to work with any amplifier/radio combination.

The input is designed to be compatible with any transmitter or transceiver, and the output is compatible with AC control lines or DC positive or negative amplifier control lines having up to 200 Volts peak open circuit voltage and 300 mA of operating current.

Why you need the ARB-704,

Amplifiers can damage radios if the amplifier has too much relay control voltage, voltage spikes, or excessive current on the relay control line. Such damage often appears as "stuck" or "sticky" transmit relays in exciters or shorted transistors on transmit control lines. In most cases where the radio is damaged, the system transmits normally but the external amplifier stays locked in a "transmit" mode. This prevents receive signals from coming through the amplifier at normal levels whenever the amplifier is in the "ON" or "OPERATE" position.

The ARB-704 has many electrical advantages over conventional relay buffer systems. The ARB-704 has no moving parts and switches almost instantaneously. It is noiseless, has a very long life, and will not develop dirty contacts. It operates with negative, AC, or positive amplifier relay control lines.

It works with any relay voltage(AC, positive or negative) up to 200 peak volts and any relay current up to 300 mA. The ARB-704 is fully compatible with conventional amplifier relay systems. It is especially suited for buffering vacuum relay QSK amplifiers since the ARB-704 does not affect attack or release times in a deleterious manner.

The ARB-704 operates with transmitters or transceivers that pull amplifier control lines to the ground or output a wide range of positive or negative control voltages. The transmitter only switches currents under .35 milliamperes and very low voltages when using the ARB-704. Measures a super compact 4-1/4W x 1-3/4H x 2-1/4D inches

The ARB-704 is supplied with the following:

1. One power connector cord and plug with red wire (+12 Volts) and black wire (- and ground).

2. Three phono (RCA) cords with connectors on each end. These cables are for relay, ALC, and amplifier control lines.

Optional connection leads are:- PNP-8D FT-1000/2000, (MP), 767GX, 920, 990, 747GX,
PNP-8M FT-890, 840, 817, 857, 897, FT450, 950, 900,
PNP-35 FT-100, (D),
PNP-5M FT-847,
PNP-7D TS-440, 690, 450, 180, 140, 950, 130, 870, 2000,50, 120, 530, 430, 830, 850, 940, 570,
PNP-13D All models of the IC-706 series, 718, 7000,
PNP-7DK TS-930 (serial numbers below 309),
PNP-8MK TS-480,
PNP-5D FT-980,
PNP-8DI ICOM ACC JACK,
PNP-7DI ICOM ACC 2 JACK.