Re: [Elecraft] Is the KIO2 line needed with external amp and auto-tuner?
On Fri, 06 Mar 2009 18:04:04 -0500, Don Wilhelm wrote: >If I recall, the signaling has been tested out to 6 feet of cable, but >it sounds like your plans will require more cable length than that. The primary issues with cable length are noise pickup and capacitance. Both can be helped a lot by using CAT5 for the serial connection. Dedicate one pair to each signal line, and connect the return of each pair to the connector shell, not pin 5. CAT5 is very low capacitance, and the very high twist ratio rejects noise and RFI. Going to the connector shell bypasses the pin 1 problem at each end. I work in pro audio, and we often have sound equipment in racks buried in the bowls of the building, but need to remote control that gear for tuning the system from within the auditorium. Doing what I've described, we often use serial over 200 ft of CAT5 at very reasonable data rates with no problems. BTW -- the RS232 standard originally quoted cable length as a limit, but was later revised to define it on the basis of capacitance. 73, Jim Brown 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
Re: [Elecraft] Is the KIO2 line needed with external amp and auto-tuner?
Duane, Not to put a damper on your plans, but to serve as a caution. The AUXBUS signal is a one wire communications channel between the K2 and its options. If the length of the cable becomes too long, there will be significant delay between a query and a response on that AUXBUS signal which will produce errors - the first may likely be that the remote option (KP100/KAT100) will not be recognized by the K2. Those signals are not all RS-232 levels, they are internal K2 signals, and that is why the connector on the K2 is labeled "AUX IO" - do not connect a standard computer serial port cable directly to the K2, it will cause damage to the K2. If I recall, the signaling has been tested out to 6 feet of cable, but it sounds like your plans will require more cable length than that. Please let us know how long a cable you have used and whether it performed without problems, I am certain several others would like to know too. 73, Don W3FPR dw wrote: > A number of you from the group have really helped me out incredibly!! > Huge thanks > > THIS GROUP ROCKS!!! :~] > > I run an SGC-237 auto-tuner outside the house. > Its the best setup I've ever had, and I don't want to lose its > functionality. > > I plan on locating the external 100 watt amp box for the K2 in a > different room. > It will be located in a room where I have power supplies and coax > line going outside to the auto-tuner. > > Since I already have an auto-tuner functioning, I'm wondering if there > is any need for the RS232 control line from the K2 to the amp box. > > I think perhaps at minimum, there is an RF-detect signal that must come > back from > the amp to the K2... if I understand the KIO2 document. > > Thanks again ALL. > Duane > N1BBR > > __ 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] Is the KIO2 line needed with external amp and auto-tuner?
A number of you from the group have really helped me out incredibly!! Huge thanks THIS GROUP ROCKS!!! :~] I run an SGC-237 auto-tuner outside the house. Its the best setup I've ever had, and I don't want to lose its functionality. I plan on locating the external 100 watt amp box for the K2 in a different room. It will be located in a room where I have power supplies and coax line going outside to the auto-tuner. Since I already have an auto-tuner functioning, I'm wondering if there is any need for the RS232 control line from the K2 to the amp box. I think perhaps at minimum, there is an RF-detect signal that must come back from the amp to the K2... if I understand the KIO2 document. Thanks again ALL. Duane N1BBR -- bw...@fastmail.net __ 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
