:
The K3/0 should allow you to control a K3 over a RS232 connection, which could be a fairly long cable (up to 50 feet, perhaps?),
Another very useful fact -- RS232 uses an unbalanced connection, and the connection is NOT impedance-matched. That is, the source has a low source impedance and the receiver has a high input impedance, so the interconnecting cable appears as a capacitive load to the driving source. A decade or so ago, we often used RS232 for the connection between a computer in the audience in a large performance space to signal processing equipment buried in the bowels of the building. We were able to reliably use runs on the order of 200 ft at decent speeds by using CAT5 cable for the connection, using a pair for each signalling circuit, by dedicating all un-used conductors to the return, and connecting the returns to the SHELL of the DB9 connectors at both ends. It works because CAT5 cable has good bandwidth AND low capacitance between the conductors of a pair, the twisted pair rejects noise, connecting to the shells at both ends gets around Pin One Problems that may be present, and doubling up on the return conductors minimizes the IR drop from AC power leakage currents that may be present because the equipment is powered (and perhaps grounded) at widely separated points.
Another method to consider for longer runs is RS422, the BALANCED configuration of the serial interface. A very good company in Illinois called B&B makes very nice, fairly inexpensive RS232 to RS422 converters. http://www.bb-elec.com/Learning-Center/All-White-Papers/White-Papers-Category1/232_422-Converter-Connections-for-Extending-RS-232.aspx
73, Jim K9YC ______________________________________________________________ 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
