Drake L75 linear amplifier

Kihwal Lee, K9SUL

The original Eimac 3-500z

The bandswitch cleaned and repaired. One arm of the 20m contact was burnt off.

It needs to be opened from the bottom to access the band switch.

The diode board. The diodes were replaced with 1N5408s. The equalizing resistors were removed and 0.01uF ceramic caps were added.

Capacitors and bleeder/equalizing resistors replaced. 150uF 450V 105 degree caps were used.

Open front panel

The input matching networks

Step start added. 10 ohm resistor and a relay.

From the top after everything done.

Output on 40m. Driven by TR-5.