The MX 300 NAV-COMM is designed to directly replace the RT328T and similar units.
In most cases the MX300 will directly replace the RT308C, RT328A, RT328C,RT328D, RT328T, RT528A, RT528E and RT508A.
With a special adaptor (MX300/540) the MX300 will replace the RT517, RT540, RT514R, RT515R and RT515A-1.
The NAV Demod output pin is on pin BB on J4 on the MX 300 and on the RT328T, RT328D, RT528E.
The RT308C, RT528A, RT328A & RT328C, however use pin L of J3 for the Demod output.
The MX 300 can be modified to output the Demod on pin L of J3.
The MX300 operates on 13.75 vdc with 7Adc maximum current in transmit.
The special adapter (MC300/540) can be placed in existing installations and locked in place.
The MX300 can then be installed by simply sliding into the MX300/540.