Drake L7 Linear Amplifier on the bench, keyed down on the Dummy Load.

Recent toy, the Drake L7 linear Amplifier, finally finished and on the bench before packing her up. The L7 was the newer version of the venerable Drake L4B. The L4B and L7 are 2-piece amplifier's with a separate power supply and RF deck. The L4 manual says Sept 75 and the L7 manual say 79. Is that right? Someone who has more insight on that, let me know. BTW, the Raytrack 2000 was said to be built in Columbus, Oh from 68-70.
So, with the L7 the first thing that's a minus compared to the L4 is that the L4 has forced air cooling while the L7 just has a fan. At least on the L7 the fan is big, and not only blows air on the tube pins, but the air cooling the tube pins is vented out too. The L7 uses the same power supply as the L4, no changes. The L4 is 10-80 meter, no WARC bands, and the L7 just added 160 meters no WARC. Build quality for the L7 is very good, but IMHO not quite up to the standard bearer, the L4. Beauty definitely goes to the L7. The layout, color scheme, pushbuttons and indicator lights all go to the L7. The L4, though a great workhorse, looks dated next to the pretty L7.
Since from factory, the L7 10 meter band is deactivated, it takes a little work to reactivate 10 meters on it. The input 'Filter' needs to be bypassed, the ten-meter stop needs to be removed from the band switch, and a couple of 68pf caps need to be added to the input tuning circuit. Also, Drake used a high-powered dropping resistor scheme to develop cutoff bias during standby. They get +120v for cutoff bias by using 2 50 watt resistors and a 7 watt resistor in series going from the HV to ground. Thats a lot of waste of power. Using Ohms Law, it's 59 watts of heat wasted in the power supply even in standby. Plus, those watts are wasted on the HV/Output side. Those power supply watts should be going to power those Z's not 60 watts wasted in heat to make bias. Modern design is to use a resistor in the cathode ground path. Since the tubes don't have a good ground with the resistor, the tubes are cutoff not drawing power and the power supply is not cooking itself wasting 60 watts either. I convert all amps that use dropping resistors from the HV for Bias to the simpler and more efficient dropping resistor scheme. Most Hams and experts on the net agree with that and many, including Harbach and Nomad, sell kits to convert the Bias to a modern scheme. Sometimes, there are better designs then what people were doing in the 60-70's. All in all, I give the L7 an 8 on a 1-10 and BTW, I give the L4 a 9. I think I plan on leaving this one as/is right now which is mostly stock, and I plan on doing some special TramDr mods on my 2nd one to see if I can push that envelope some.