Jerry -
The VOX connector is the transmit enable connection (PTT). The AGC connection is for rigs that accept external ALC, and may not be needed with the K3. Normal drive for full output is when 240 mA of grid current is indicated when fully loaded. Use the SSB setting on the plate switch for both CW and SSB. The lower voltage / lower power setting is from when we were limited to 1000 watts CW input, 2000 watts PEP for SSB. The amp will make about 1300 watts (low bands) to 900 or 1000 watts (10 meters) if you have good tubes. Simple adjustment procedure: watch the power output, tune for max using the plate and load controls. The panel markings will get you close enough to start. Recheck the grid drive to make sure you are not exceeding 240 mA and you are good to go. Both the tubes and the power supply are very forgiving, so temporary overloads will be well tolerated. I have used both the L7 and its earlier cousin, the L4B, for many years,. and never had a problem, even when running full-blast key-down modes like RTTY. You may wish to make a mod to the fan circuit to keep the blower turning about half-speed at all times, instead of depending on the thermal relay to start the fan when the amp is getting too hot. Simply wire a 300-ohm / 25-watt resistor across the thermal switch to accomplish this. The fan will still go to full speed if needed, but mush less often, and the amp will last much longer. Be sure to observe normal safety precautions when working inside the cabinet - disconnect the power completely, both from the wall outlet and the PS from the amp, including the HV connection before opening the cabinet. - Jim, KL7CC . Jerry Dwyer wrote: > I just got a good deal on a very clean Drake L-7 amp (2- 3-500Z tubes). I > was hoping someone might know how to connect them together. The amp has the > normal RF in and out connectors. It also has two rca connectors, one says > VOX and the other says AGC. > > > > Thanks for any help > > > > Jerry - NF9L > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
