SYNTOR CONTROL HEAD & CABLE INFORMATION 
(under construction)

The 16 channel control heads use a 16 position binary channel switch that selects the channel using channel select pins F1, F2 F3 and F4.  The Syntor uses an interface IC that normally reads the channel select lines individually, but when channel select lines 11 and 12 (pins 33 and 34) are tied to ground it reads PIN 4, 14, 13 and 5 in BCD (Binary Coded Decimal) format.  

The 32 channel Syntor uses an additional channel select pin (F5) to select the second bank of 16 channels. 

Memory Expansion with a 16 channel Control Head

The SAB module is capable of 32 channels without any modifications to the SAB.  In order to access the 2^nd bank of channels: 

        Remove JU1101 (near the PROM socket inside the radio)
        Add a toggle switch to ground on channel select pin 23. 

When Pin 23 is grounded you will  be on bank 1, when Pin 23 is not grounded you will be on bank 2.  The “R/D” or “A/B” switch on a 32 channel control head is factory wired to serve this purpose. 

this modification only works with 16 channel control heads.  See the SAB Memory Expansion page for adding channel banks with other types of control heads.