Speaker amplifier modification: In the AF stage upgrade instruction page 1 it is mentioned: “This mod changes RFC 47, 100 µH radio frequency choke that supplies power to the K3 audio amplifier. The original choke has a resistance of about 1.5 ohms. This resistance is high enough to cause some clipping of the audio signal at moderate volume settings, resulting in distortion products about 40 dB down. Replacing this choke with a physically larger unit with a resistance of about 0.2 ohms results in a 20 to 30 dB reduction in most distortion products”
On the K3 circuit diagram RFC47 is marked with a value of 10uH. I plan to buy this choke locally “because the high shipping charges for the kit to Switzerland”. Which value is now correct 10uH or 100uH? 73 Willy HB9WI -- View this message in context: http://n2.nabble.com/K3-AF-Upgrade-Kit-%28for-speaker-amplifier-and-LINE-OUTs%29-tp1495036p1558365.html Sent from the Elecraft mailing list archive at Nabble.com. _______________________________________________ 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
