My XV50, fed by my K2 through an XV60 transverter adapter always emits 20 watts of power regardless of the power setting on the front panel of the K2.
The XV60 ALC circuitry seems to be working. I've measured pin 6 of J13 on the XV60 using various power control settings and I get the expected results. At 1.00 LP, pin 6 measures 3.51V, the K2 LCD reads 0.94 and the watt meter reads 22 watts. At 0.50 LP, pin 6 reads 2.50V, the K2 LCD reads 0.48 and the watt meter reads 21 watts. At 0.10 LP, pin 6 reads 1.54V, the K2 LCD reads 0.10 and the watt meter reads 21 watts. I can't measure at K2's R66 as the KNB2 is in the way but I did do a continuity check between pin 6 of J13 and R66 and had a good connection. I tried adjusting the RF power level with R22 on the XV50 and had good results. R22 controls the output power fine. Using R22, I dropped the maximum XV50 power out to 10 watts and rechecked the voltages at pin 6 of J13. They remained the same as listed above with the exception of the watt meter which consistently read 10 watts out instead of ~20. So now I'm stumped. The XV60 ALC is correctly reading and responding to the TXRF on the XV60. There is nothing between the XV60 TXRF and R22 on the XV50 and R22 provides a bias to Q6 which, in turn, controls the output level. I've checked all the components on the XV60 ALC circuit and all those associated with the Q6 level control circuitry; I've also checked and double checked the all the jumpers for the XV60 low power installation and they are correct. The XV50 both transmits and receives on frequency, so the basic circuitry seems to be OK. Either Q6 is bad or I'm missing something (probably the latter). _______________________________________________ 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
