In the real world, there's not much advantage to using both the attenuator and preamp together. The preamp offers about 14 dB gain. The attenuator offers about 10 dB attenuation, so using both of them produces an effective preamp gain of about 3 dB.
Since the purpose of the preamp is to provide enough gain to override internal mixer noise on the higher frequencies where band QRN is very low, and the purpose of the attenuator is to reduce the gain when band QRN is very high to improve the dynamic range of the receiver, using both of them gives you the ability to "tweak" the gain slightly by 3 dB instead of steps of about 10 to 15 dB. That might be useful when trying to keep the gain down to the absolute minimum needed to avoid overload where several rigs are working next to each other, such as a field day setup, but that's about the only situation where I could envision that such fine adjustment might be of value. Ron AC7AC -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mike Markowski Sent: Sunday, February 18, 2007 10:22 AM To: Elecraft Subject: [Elecraft] K2 preamp & attenuator combos I'm writing some rig control code for the K2 and came across this in the KIO2 manual at the PA command: "Note: the preamp and attenuator can be turned on simultaneously under computer control to provide four different RF gain levels." Two variables each with two settings gives you four combinations. Easy enough, but does it really buy you anything to turn on both the attenuator and the preamp simultaneously? 73, Mike ab3ap _______________________________________________ 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 _______________________________________________ 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
