 | 2000 watts PEP SSB-1000 watts DC input power on CW, AM
and RTTY. Massive plate transformer, large heavy duty plate tank components and voluminous
cooling system insure continuous operation at these ratings. |
| High efficiency Class B Grounded Grid circuit uses two
3-400Z or 8163 zero bias triodes. These two tubes have a total plate dissipation rating of
800 watts and their rugged construction withstands abuse. |
| A broadband tuned input circuit is employed on each
band for minimum distortion, higher efficiency and a 50 ohm input impedance. |
| The L-4 Linear Amplifier matches the TR-4 Transceiver
and the T-4/T-4X Transmitters in appearance and drive requirements to run the maximum
legal input power. Any exciter that can deliver 100 watts |
| PEP SSB and 75 watts on CW will be able to drive the
L-4 to the maximum legal input power. An advantage of the Grounded Grid Circuit is that
most of the driving power adds to the output power. |
| RF negative feedback decreases distortion to better
than 35 db and tends to equalize tube characteristics from tube to tube and from brand to
brand. |
| A transmitting AGC circuit controls the exciter gain to
allow a higher audio level without peak clipping. An adjustment is provided to set the
threshold level for optimum operation of different exciters. |
| Rapid heating filaments and the solid state power
supply allow the L-4 to remain off until its use is required. It needs only 3 seconds from
switch on to 2000 watts. |
| Two taut-band suspension meters indicate plate current,
grid current, plate voltage, and relative RF ouput power. The frictionless suspension
eliminates sticking and improves accuracy. |
| An internal changeover relay feeds the antenna through
when on receive or when power is off. A pair of relay contacts bias the output tubes to
cut off, eliminating any diode noise when receiving. |
| A quiet, low velocity, high volume internal blower
effectively cools tube base seals, envelopes and plate seals. |
| The solid state Power Supply provides excellent dynamic
and static voltage regulation. The Power Supply is separate to keep the weight off the
operating desk and to make a more flexible installation. |
