Thank you Don for that, a very useful reply. There is obviously a lot more to it than I expected, and your explanation will help me to understand the way the link works. A rethink now needed on the whole thing, 73, Harry M0SOP
--- On Sat, 26/1/13, Don Wilhelm <[email protected]> wrote: From: Don Wilhelm <[email protected]> Subject: Re: [Elecraft] Can Bluetooth be used to replace link between K2 and remote KPA100+KAT100 To: "harry weston" <[email protected]> Cc: [email protected] Date: Saturday, 26 January, 2013, 18:01 Harry, First, the signals required to operate the KPA100/KAT100 remotely are *not* RS-232 signals.They are 'hard-wired' signals to and from the base K2. Note that the connector is labeled AUX I/O - the fact that there is a DE-9 connector on any piece of equipment does not denote RS-232 unless explicitly stated, and the K2 is no different. Secondly, I believe you will encounter timing problems on the AUXBUS signal (the one wire K2 signalling line between the firmware ICs in the Elecraft gear. It will likely work up to 2 meters, but 10 meters is stretching it a lot. You would have to do extensive testing to determine that 10 meters of cable will work with no problems. The AUXBUS carries data that requires a response in a certain period of time and that timing is critical. The other internal signals used to connect the KPA100/KAT100 are not likely to cause problems unless the cable resistance is a problem. Those signals are: +12CTRL - this is a 12 volt line that is active whenever the K2 is powered on. 8R ---- this signal controls the transmit/receive switching, Whether propagation delay would prove troublesome over a great cable distance remains to be tested. VRFDET -- This carries the measured power output from the KPA100 wattmeter back to the base K2 so power output control can be maintained. Again the resistance of the wire may be a factor in correct operation. Better to bring your KPA100/KAT100 inside in the warmth of the shack and just run the output coax(s) to the shed and antenna field. 73, Don W3FPR On 1/26/2013 12:16 PM, harry weston wrote: > Hello. I am assembling KPA100 and KAT100 into an EC2 case, and intend to use > the K2 indoors, where I can keep snug and warm, with the amplifier and tuner > in a shed outside, less than ten metres away, and close to the antenna. Can I > use a Bluetooth RS232 serial replacement pair for this communication link? I > am concerned because we are warned against using a standard RS232 cable to > link them, and the Bluetooth modules are rather expensive to buy for an > experiment, unless I am pretty sure it will work. Thanks, Harry Weston M0SOP > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
