Hello everyone. I am new to this list, so thought I would briefly introduce myself. My name is Lyman Hays, K7LH. I am an electrical engineer in practice for many years. My primary field of interest is RF design below 3 GHz.
In viewing the archives, I see names I recognize from the Central-Electronics mail list. To them I say "It's nice to see you again." For one of my personal projects, I want to acquire one or more AM transmitters I can experiment with. So I am looking for transmitters of the type used for AM broadcasting. Want something in the 500 to 2000 Watt range, preferably 1000 Watts (so I can use my existing attenuators and loads and single phase power). The transmitters must be all solid state. Typical examples include: Harris SX-1A, Gates One, Armstrong 1000B, Omnitronix AM 1000A, etc. My interest in these transmitters is two-fold. First, I want to study efficiency and linearity aspects of pulse duration modulation, results perhaps leading to improved amplifier designs. Second, I want to evaluate the task of converting solid-state AM transmitters for ham use. I understand some PDM designs impose frequency limitations due to the relatively slow switching speed of the power transistors. I suspect the best place to find used transmitters may be at radio stations who are surplusing gear, but I don't know of any efficient way to contact them. Does anyone have any ideas here on how to obtain used AM transmitters? Lyman
