On Tue, 30 Nov 2004 15:51:22 +0100, McNamara, Philip wrote: > Response to Stewart G3RXQ > I have also experienced the strange effect of no audio out after switch on. > My K2 has been operational for about 3 months now and I have noticed the > problem only about 4 or 5 times. I just switch it off and then back on again > and everything is ok. Next time I will probably try to analyse the problem in > more detail. The problem was never apparent when I completed the basic K2 it > only became noticable after the option boards were added. > Just for information I have the noise blanker, SSB, ANT-Tuner and DSP options > fitted. > > 73 Philip DB3LMN > _______________________________________________ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com
Hi Phillip, Sorry to hear about your problem. I don't know if there is any similarity with what I am getting. Question:- Do you have a microphone with an in-built pre-amp that uses the K2 +5v for it's supply ? If so it maybe loading the 5A rail and affecting the MCU reset. Unlike many microprocessor circuits the K2 MCU relies on the 5V (5A) rising to +5v during a certain period. If it doesn't, then because the Reset (MCLR) is the same signal as VDD it may not intialise the control program cleanly giving unpredictable results. I will look to see if the option boards use this rail. When you have the problem check the voltages on 8T,8R and MUTE. 73 Stewart G3RXQ _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
