hi Stewart, On 8 Jan 2008 at 10:27, Stewart Baker wrote:
> Hi Werner, > I would not recommend this approach. > > The +5v from the Mic connector is for delivering a low current. > It is susceptible to interference both in and out of the K2. > > In addition any spiking on the +5V will effect the control board MCU > due to poor design of it's reset circuitry. > > If you are happy making mods, then you can try this. > > I put in a separate +5V supply to the Mic connector by using a 5V > regulator mounted on the front panel board and fed from the 8A line on > the RF board. There is a spare connector pin/socket (Pin 7 on J1) that > is labeled AUXBUS(NC) which can be used to get the +8V thru. Of course > the existing feed must be disconnected. > > 73 > Stewart G3RXQ thank you for your advice . I'll make a separate power supply. There is enough room for an 7805 voltage regulator on the relais board I have added to switch the TrxPtc in my K2. This way I avoid any problem you have mentioned. 73! de Werner OE9FWV -- Wenn du deine Frau so hasst, warum schenkst du ihr nicht einen PC mit Windows95? PGP-Key: <http://www.qsl.net/oe9fwv/furlan.asc> Fone +43 5522 75013 Fax +43 820 555 85 2621 Mobile +43 664 6340014 _______________________________________________ Elecraft mailing list Post to: [email protected] 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
