K2 # 4670, finishing up test and alignment of a KPA-100. Page 46 (all checks within norm to here) Two Questions 1 - External Amplifier Keying Test (PA KEY) Use the MODE switch to select CW mode (mode letter changes to C). Enter CW TEST mode by holding VOX. The letter C should now be flashing. In this mode, the K2 will not put out any power when you key the rig either with a key or with the TUNE switch. Set your DMM to its lowest resistance scale. Connect the (-) probe to ground, and touch the (+) probe to the tab of Q9 on the KPA100 board (or to the center conductor of the PA KEY output jack, J7). The DMM should be indicating a high resistance (typically indicated by a flashing display). OK to here - Hold TUNE on the K2 to key the transmitter. The resistance reading should drop to less than 3 ohms. THE OHMS start dropping, but before I can pull the + probe off the Q9 tab, something clicks/pop and the K2 drops out of the tune mode (sort of like of a reset?) IS THIS WHAT IS SUPPOSED TO HAPPEN? OR ???? The MM shows 3 OHMS at this time. Never get to this part - Tap any switch to exit TUNE mode. Exit CW test mode by holding VOX. The mode letter will stop flashing.
2 Bias Current Adjustment Connect the (+) lead of the DMM to the power supply side of the circuit, and the (-) lead to the KPA100 side. Turn on the high-current power supply, then turn on the K2. EXACTLY WHERE DO I CONNECT THE + AND - LEADS? 73, KI4HRN _______________________________________________ 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
