RE: [Elecraft] Binaural CW tuning
Look in Experimental Methods in RF Design. The article there also references a lot of QST articles. Mike Scott AE6WA Tarzana, CA (near LA) Elecraft KX1 4-Watts -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of pa3gyu Sent: Thursday, May 25, 2006 12:34 AM To: elecraft@mailman.qth.net Subject: [Elecraft] Binaural CW tuning Vic Wrote: I've always wanted to try some kind of crossover device that would distribute the signal between the two earphones according to frequency. Then as I tune through a CW signal, it would seem to move. This has been on my mind too for a long time. I even seem to recall I've got a schematic saved somewhere for a circuit that does just that, so somebody beat us to it. I just never came around to built and test it for myself For details, contact me offline and I'll try to dig up the circuit. I'd expect the hiss that 'll always appear in one ear to cause fatigue. Anybody 'been there, done that' and willing to tell us about it? Bart de PA3GUY ___ 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
Re: [Elecraft] Binaural CW tuning
Bart PA3GUY wrote: This has been on my mind too for a long time. I even seem to recall I've got a schematic saved somewhere for a circuit that does just that, so somebody beat us to it. I just never came around to built and test it for myself For details, contact me offline and I'll try to dig up the circuit. I'd expect the hiss that 'll always appear in one ear to cause fatigue. Anybody 'been there, done that' and willing to tell us about it? -- Back in 1973, G3OTK suggested a high pass - low pass filter scheme to obtain a pseudo-stereo effect for binaural reception, and I believe that his filters 'crossed over' at 500Hz. I would agree that something would have to be done about hiss coming from the 'high frequency' channel, but it might have to be something more clever than just adding a low pass 'hiss filter' - I don't know. PA0CX came up with a very interesting scheme in 1958 named 'Frequencieschaar' which split a double sideband AM signal into two halves so that a pseudo-stereo audio output could be obtained. This helped to overcome the problems of selective fading and QRM. Also in Chapter 9 of 'Experimental Methods in RF Design' by W7ZOI, KK7B and W7PUA there is an example of a simple binaural receiver taken from QST, March 1999. Personally I like to use binaural reception. Why is difficult to explain, but the effect is like being 'inside' the band with signals on each side which helps the a lot when trying to listen to one signal amongst the QRM. 73, Geoff GM4ESD ___ 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
Re: [Elecraft] Binaural CW tuning
Hello all, An idea for the KDSP2 option? Use the DSP to generate the 90deg delay for the I-Q outputs. Taking these two outputs (at or near the drains of FETs Q6 and Q7) to an outboard dual pot and stereo headphone amplifier could be a simple way to experiment with this mode. My knowledge of DSP is very limited but I base this idea on KK7B's binaural receiver in the ARRL handbook. 73 de David VK5DG ___ 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
