Power voltage: 13.8 V (12 to 16V )
Current consumption: max. 1 A
Dimensions: W 175 mm (6,89") x H 44 mm (1,73") x D 130 mm (5,12")
Weight: 700 g (1,54 lbs)
Operating temperature range: 0 .. 55 °C (32 .. 131 F)
Inputs :

   • 13.8 V DC input (up to 300mA without micro STACK SWITCH)
   • RS 232 input from PC

PTT input for hot switch protection

Outputs :

   • 8 x source or sink outputs with capability of 700 mA both
   • output for LCD display - Info Panel
   • INH output, open collector max. 12V, 100mA sink - direct connectible to Yaesu's QSK signals

RS 232 for PC controlling and configuring






micro STACK MAX buttons layout
Function Buttons :
Three buttons control special functions of stack.
T/R button - Pressing this button, divide combinations of the stack to separate combinations for receiving and for transmitting. A LED indicates when this function is active. Change the combination of stack using the antenna buttons - change the "receiving" combination during receiving and change the "transmitting" combination during transmitting. As the transmitting combination can not be changed immediately while transmitting (hot switch protection), the new configuration will become active after releasing PTT, and after reengaging PTT you are transmitting to the newly chosen combination. Press the T/R button once more to switch this function off. The combination of stack both for receiving and transmitting will be now the same as the last one chosen for receiving.
BOP button - switch the stack out of phase pressing this button. You can freely combine functions BOP, T/R and AUX. Press the button again to change or switch off the BOP function. The stack will switch to the last combination before switching BOP on.
AUX button - Pressing this button one antenna will be excluded from the stack and switched to a separate feed. If no antenna is free, a previously configured antenna will be chosen as the default. Pressing AUX button repeatedly change the antenna to be excluded from the stack and connected to a separate feed. Press and hold the AUX button for a while to switch the AUX function off. The configuration of the antennas will be restored to the combination just before the function has been switched on.
Memory write :
Any combination of the stack (including the special functions) can be stored to one of four memory positions. Store the combination by pressing and holding T/R button ; then choose the memory position pressing one of the buttons 1 to 4. Restore the stored combination simply by pressing one of the buttons 1 to 4, when in memory mode.
Antenna Button Modes :
Use the antenna switches to choose the active antenna in the stack. Antenna switches can be configured to three modes. Choose the required mode by pressing and holding T/R button, then press BOP button for mode 1 and 2 or AUX button for mode 3.

Switch between antennas simply pressing the appropriate antenna button. All other antennas will be disconnected. When there are two or three antennas (the number of antennas is configurable), pressing button 4 all antennas can be switched into the stack. Two or three antennas can be chosen together by simultaneous pressing the appropriate antenna buttons. This mode is recommended when using two or three antennas in the stack.

MODE 2 - TOGGLE mode

In this mode, pressing an antenna button switches the antenna on and repeated pressing switches is off. There is always at least one antenna switched on. When using two or three antennas, pressing button 4 switches all antennas in the stack on. This mode is recommended for three or four antennas in the stack.

MODE 3 - MEMORY mode

In this mode, pressing buttons 1 to 4 chooses previously stored combinations of the stack (stored together with the special functions). Functions of the stack can be changed by the function buttons. Pressing any antenna button restores the previously stored combination appropriate to the pressed button. This mode is used for fast switching between four optimized configurations of the stack.

Maybe this all sounds complicated, but in fact it is very simple and easy to use and you will learn all the features within a couple of minutes.