One source of noise is in the K2 audio amplifier. It isn't much of a problem with the standard speaker since there is a built-in high frequency roll off. However, if you use very good quality earbuds that were designed for music, the hiss comes through loud and clear. I like to use the buds because they block out virtually all ambient noise and let me concentrate on CW. (I need all the help I can get). I have ordered some sample chips from National Semiconductor to see if a low noise headphone amp will improve the situation. I probably won't get the chips for another two weeks and will have to spend some time experimenting, so I probably won't be able to report for a while, but will report back when I do. Howard W. Ashcraft, Jr. W1WF Hanson, Bridgett, Marcus, Vlahos & Rudy 425 Market Street, 26th Fl. San Francisco, CA 94105
ph: 415.995.5073 fax: 415.541.9366 e: [EMAIL PROTECTED] ________________________________ From: Darwin, Keith [mailto:[EMAIL PROTECTED] Sent: Tue 5/16/2006 6:45 AM To: [email protected] Subject: [Elecraft] K2 AF noise level? Hey 'Crafters, I'm debating between the KAF2 or an outboard audio filter for my K2. Possible choices are the SCAF-1 and an Autek QF1A. My goal is to greatly reduce the hiss that is there in the headphones when the narrow CW filters are engaged. I'd also like to add some CW selectivity. A notch would be great too. KAF2 has the benefit of being integrated into the rig but doesn't offer lots of flexibility. The others are external but give you more control over the filtering. How well does the KAF2 kill the hiss? I assume it does great for that. Does it add any noise back in? - Keith KD1E - - K2 5411 - ***************************** This communication, including any attachments, is confidential and may be protected by privilege. If you are not the intended recipient, any use, dissemination, distribution, or copying of this communication is strictly prohibited. If you have received this communication in error, please immediately notify the sender by telephone or email, and permanently delete all copies, electronic or other, you may have. To ensure compliance with requirements imposed by the IRS, we inform you that any tax advice contained in this communication (including any attachments) was not intended or written to be used, and cannot be used, for the purpose of (i) avoiding penalties under the Internal Revenue Code or (ii) promoting, marketing or recommending to another party any transaction or matter addressed herein. The foregoing applies even if this notice is imbedded in a message that is forwarded or attached. ***************************** _______________________________________________ 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
