The 30S-1 is the original S-Line amplifier covering 80 - 10 meters. This amplifier uses a 4CX1000 in the final.  The HV (high voltage) time delay is sometimes bypassed because the owner did not have a ready supply of time delay tubes. The amplifier can be modified to output about 1000 watts by adding a 1:1 transformer in the screen and changing the final to a 4CX1500B (See the Collins Reflector archives for a complete description - Links Page).