TTI TCB-881 - Manual (Page 5)

ENGLISH
It is very important to select a good quality high efficiency
27MHz antenna. A poor quality antenna or one not designed for
the 27MHz band will give very poor performance and could
cause damage to the transceiver.
1) Place the antenna as high as possible.
2) The longer the antenna is, normally the better is the
performance of the transceiver.
3) Try to mount the antenna in the centre of the surface that
you select.
4) Make sure that you have a solid metal to metal ground
connection.
5) Be careful not to damage the cable during the installation.
Installing An Antenna
Warning : Never try the operation of your transceiver before
connecting a proper antenna in order not to cause any damage.
5 TCB 881