Don Wilhelm-4 (via Nabble) wrote: > Andrew, > > Check the base K2 first. > First of all, if your K2 is less than SN 3000, you must have the > sidetone source mod on the Control Board. It is easy to check - if that > mod is installed, there will be a wire to P4 pin 1 that you can see > without removing the Control Board. > Next, check to see if you have sidetone on that K2 - the sidetone source > must be U8-4. > Also be certain PORT is set to ON in the secondary menu. > > Having finished those preliminaries, it is time to drag out the 'scope, > but first you need some signal source at the RS-232 connection. It is > easiest if you use a software application that continuously polls the K2 > in an attempt to connect. I have the N2PK software which continuously > tries until it is closed. HRD tries to connect for a bit and then gives > up, so your 'scoping time is limited to the time the application tries > to connect. > > What should you see - on the MAX1406 chip pin 6 you should see the input > RXD signal coming from the computer. It should swing between more than > 3.5 volts positive to more negative than 3.5 volts. > If that is present, then the input signal is getting to the chip - if > not, check the inductor RFC7 or the computer cable. > That RXD input signal should result in a signal out of U4 at pin 11 > which has the dame data pattern and swings from 0 volts to +5 volts. > That same signal should get to the K2 control Board U6 pin 26. > > OK, that is the received data part. Upon receiving data, the transmit > data should be generated by Control Board U6 and come out at pin 25 with > a voltage swing between zero and +5 volts. > That signal should make its way to KPA100 U4 pin 12. > The MAX1406 converts the levels to RS-232 and the TXD signal should come > out of U4 pin 5 with both a negative and positive voltage swing - goes > through RFC6 and should be sent on to the computer. > > So now you know the 'full story' - good luck with the 'scoping. > > 73, > Don W3FPR > > Andrew UK wrote: > > Hi Don, > > I was thinking along those lines, I was hoping the K2 could put put a > constant test data stream for me to treace, ok will connect a PC with > N2PK software, My serial numberis over 5000, but I lost the plate, I > will order a new one. > > I will let you know the ourcome. > > 73's > > Andrew>
> Hi, > > > > After 3 years I decided to use my RS232 interface, however it does > not work, > > I measured the voltages and only had -1 volt on pin 8!!! I thought > the Max > > 1406 maybe faulty so change it and also fitted an ic socket, still > -1 volt > > and -2.5 with the ic removed. fault traced to C38 it was cracked! > replacing > > this I now have -12 Volts. However still no comms. I am using the > correct > > elecraft lead. > > > > PC works with an FT847 using a null modem lead so the PC serial port is > > working. > > > > can anyone (Help Don) give me some guidence to fault find, if I > scoped TXD > > going in to the Max 1406 what should I expect? > > > > 73's > > > > Andrew > > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:elecr...@... > <http://n2.nabble.com/user/SendEmail.jtp?type=node&node=3148253&i=0> > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > > ------------------------------------------------------------------------ > This email is a reply to your post @ > http://n2.nabble.com/RS232-KPA-100-Problems-tp3147911p3148253.html > You can reply by email or by visting the link above. > -- View this message in context: http://n2.nabble.com/RS232-KPA-100-Problems-tp3147911p3148817.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ 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
