Hi Lyle, Thanks for entering the discussion. It's great that the company guys monitor these reflectors.
Even at its maximum 030 setting, the AF Limiter is problematic. The K3's AF Limiter is a HARD limiter that has an abrupt onset and causes extreme distortion. In fact, once the AF Limiter threshold has been hit, the louder the signal is, the less audio comes out of the headphone amp, at least as measured on my DVM. Once the limiter is hit, there is absolutely no hope of pulling a signal out of the pileup. One absolutely must reduce AF or RF gain to pull anything out at that point. A soft limiter on the other hand (such as a pair of back-to-back Schottky Diodes) doesn't cause that extreme distortion, and allows a much wider usable dynamic range, albeit with some minor fuzz on very loud signals. There is no way, despite K3NA's excellent attempt http://wiki.contesting.com/index.php/Setting_receiver_gain_controls to set the K3's RF and AF gain controls to accommodate the dynamic range of signals encountered on the bands, without riding the RF and/or AF gain controls. Maybe it is possible with super-sensitive headphones, but not with any that I have tried. The most successful method of dealing with pileups that I have found (other than agc OFF, and constantly riding the RF gain) is to use an external audio amp with a soft limiter. I wonder if there is a place in the K3 to put a pair of limiting diodes, ahead of the AF Limiter? Dave Hachadorian, K6LL Yuma, AZ -----Original Message----- From: lyle johnson Sent: Sunday, December 05, 2010 11:18 AM To: Elecraft Reflector Subject: [Elecraft] AF Limiter (was Recommended AGC settings for separation of signalsin CW pile-ups) The AF Limiter in the K3 is designed to allow you to protect your hearing when you have the AGC off and gain cranked up to hear the signal buried in the noise just as your neighbor with his beam bore-sighted on your QTH and running the Alpha amplifier starts transmitting on that same frequency. Note that the AF Limiter level is completely adjustable when AGC is OFF. At its highest setting it clips just at the threshold that the audio amplifiers in the K3 otherwise limit/clip. In fact, when AGC is ON, the AF Limiter is still present but set to this highest level. So, if it bothers you, please set it higher :-) Enjoy! 73, Lyle KK7P (at 38,000 feet enjoying in-flight WiFi) > you have to deal with the crazy AF Limiter. ______________________________________________________________ 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 ______________________________________________________________ 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
