View of the amplifier

The channel amplifier is pre-tuned to a desired channel by the producer - making an order it is essential to give the number of the channel that is needed.

ZG-421 amplifiers (enhanced version of ZG-01) are channel amplifiers having improved parameters needed for networks with active adjacent channels. Admittedly, the ZG-401 ones can be also employed for such work, but on the condition that the levels of the input signals are very similar as with satellite receivers in cable head station. Terrestrial TV signals do not assure that condition and force at least one-channel gap, e.g. using only even channels (..50-52-54-56..).

Terrestrial DVB transmitters will use adjacent channels, and the choice of proper installation equipment is essential even now in order to guarantee future compatibility. The use of channel amplifiers with increased selectivity - like ZG-421 - will ensure fulfillment of any technical demands. The new model can be used together with the current ZG-401.

Characteristics of ZG-401 (blue) and ZG-421 (red) amplifiers. It is clear the selectivity of ZG-421 has been considerably improved.