Al, What are you using to determine the 3 volts? The Band Data output lines are pulled up to 5 volts by a 2.2 kohm resistor. If the device you are measuring with has a load of 3.3k, the voltage measured would be 3 volts.
BTW - the switching level for TTL (or CMOS) is +1.5 volts, so 3 volts will be interpreted as a high level with no problem (and plenty of noise margin). Typically the low level is the one that causes problems - check to be certain the voltage for the non-active band data lines is 0.5 volt or less. 73, Don W3FPR Alfred Frugoli wrote: > Hello, > > I'm working on wiring up a band decoder to the ACC port on the back of the > K3. I'm seeing 3V when a BCD pin is active. The rig is SN 4094. The > manual says that "older" rigs may need a pull up resistor. I wouldn't have > thought that a brand new out of the warehouse rig would have been an "older" > K3. Am I missing something? > > Thanks. > > 73 de Al, KE1FO > > ______________________________________________________________ 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
