Skanti TRP 5000, Инструкция по эксплуатации

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5.10.3 /267\
HT-RECTIFIERS A
HT-transformer 267 T2 has six secondary HT-windings. Each winding is
connected to a bridge rectifier and the DC-outputs are series connected
to obtain the anode supply voltage for the Transmitter Power Amplifier,
while the DC-output from the second bridge above ground is used as
screen grid supply voltage.
When the MODE switch of the associated Exciter is set to Fl, the anode
voltage is lowered by Opening the contacts of relay RL1 and thereby the
anode dissipation in the Transmitter Power Amplifier is decreased.
5.10.4 /268\ DRIVER AND GRID VOLTAGE STABILIZERS
An output voltage from the HT-transformer 265 T2 is fed to rectifiers Dl
and D2 followed by a voltage stabiliser having a nominal output voltage
of 28V.
An output voltage from the transformer 265 T1 is fed to bridge rectifier
D3, D4, D7 and D8 followed by a zener diode stabiliser. The stabilised
voltage is negative with respect to chassis and is further stabilised i n
the Transmitter Power Amplifier to be used as grid voltage.
To avoid the transmitter being keyed before the filaments of the P.A.
valves have reached their operating temperatures a 30 seconds timer is
included. The timer is composed of integrated circuit 1G1 and will
commence the timing period when the POWER switch 265S2 is turned from
RECEIVE ONLY to STANDBY. Until the 30 seconds period has elapsed the
keying relay cannot be operated.
The board contains also a filament-voltage rectifier D5 and D6, and
relay RL1 is used to apply power to the blower in the Transmitter Power
Amplifier.