Rich; The KRC2 manual is correct. It is a matter of understanding the frame of reference for the markings. The KRC2 was originally designed as a peripheral for the K2, so the interface ports use the K2 I/O port details. On the KRC2 schematic, 8R, VRDET, 12CTRL, ALC and AUXBUS are all K2 signals that the KRC2 can use for various functions. When used with other transceivers, they are repurposed (the benefits of using a microprocessor) to make best use of that device.
The KRC2’s Icom band voltage sensing makes use of a feature of the processor, that is a voltage reference pin that exists only on the AN3 port, which is connected to pin 4 of the DE9 connectors. This particular setup was added late in KRC2 development to resolve issues with Icom’s band voltage system. It requires that the actual band voltage be connected to ANA1 of the micro, which is pin 9 (marked 8R) on the DE9 connector. Again, the 8R and ALC schematic markings have nothing to do with Icom signals, but reflect signals on the K2 IO port. I will communicate with you directly to try to resolve your issues shortly. We sometimes make mistakes, and this question caused me to recheck the schematics and code, but rest assured that in this case the manual and schematic are correct. 73! Jack, W6FB > On May 20, 2020, at 3:34 PM, Rich <[email protected]> wrote: > > I had been in conversation with Elecraft Tech Support, but I have not heard > back from them in three weeks. So I will throw this out to the group. > > It appears that there is an error in the KRC2 manual and it is not shown in > the Errata sheet. > > On page 24 the manual states the following when connecting the KRC2 to an > Icom radio: > > "For this reason it is recommended that the reference input setup be used. In > this configuration, the band data is connected to pin 9 and the 8 volt > reference is connected to pin 4. This mode is set with jumpers W1, W2 and W3 > installed." > > Directly below that statement this statement appears which confirms the first > statement: > > "• Analog band input on J1/2 pin 9 with reference voltage on J1/2 pin 4:" > > If you look at the schematic it shows Pin 9 as Reference voltage (8v) and Pin > 4 ALC (band voltage) > > So they are reversed. > > Since the wording and the schematic disagree. > > Does anybody have any idea which is correct? > > My unit is not working properly. I sent it in for repair but 1 hour of labor > is about the cost of the unit. So they returned it and I am trying to > troubleshoot it myself > > Rich > > K3RWN > > > > ______________________________________________________________ > 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 > Message delivered to [email protected] ______________________________________________________________ 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 Message delivered to [email protected]
