Re: [K3] [Elecraft] Rx/Tx equalization
Jack Smith-6 wrote: Looking at the audio output in monitor mode with a spectrum analyzer misses parts of the audio chain ahead of the transceiver. Why would you miss any effects that were upstream of the monitor? 73, Barry N1EU -- View this message in context: http://n2.nabble.com/Rx-Tx-equalization-tp781488p782036.html Sent from the [K3] mailing list archive at Nabble.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: [K3] [Elecraft] Rx/Tx equalization
Bad choice of words - what I was getting at is that you are looking at the composite of the microphone and the transceiver's audio processing. It would be useful to look at each separately. This suggests looking at the microphone individually, into an audio spectrum analyzer and also looking at the transceiver response with a swept tone to understand what is going on in both as well as looking at them with normal speech when connected. Jack Barry N1EU wrote: Jack Smith-6 wrote: Looking at the audio output in monitor mode with a spectrum analyzer misses parts of the audio chain ahead of the transceiver. Why would you miss any effects that were upstream of the monitor? 73, Barry N1EU ___ 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: [K3] [Elecraft] Rx/Tx equalization band selection
Jim Brown-10 wrote: 50 Hz and 100 Hz octave bands are VERY important Why is 50hz important if it is completely outside the passband? +/-16dB at 50hz has zero effect on rx or tx in the K3. 73, Barry N1EU -- View this message in context: http://n2.nabble.com/Rx-Tx-equalization-band-selection-tp779103p780224.html Sent from the [K3] mailing list archive at Nabble.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: [K3] [Elecraft] Rx/Tx equalization band selection
On Sun, 24 Aug 2008 14:41:54 -0700 (PDT), Barry N1EU wrote: Why is 50hz important if it is completely outside the passband? +/-16dB at 50hz has zero effect on rx or tx in the K3. Don't be so sure that there's no effect. It's important that when this undesired low frequency energy is produced by the mic, it is not carried through AUDIO path where it can trigger limiting, create distortion, or even cause overload. On the air, especially during contests, I hear lots of low frequency trash on SSB signals, most of it room noise. In general, if the desired bandwidth of a system is limited, as ours is, the modulating signal (in this case, microphone audio) should be bandwidth- limited as early in the signal chain as practical. Many good mics have built-in high pass filters or low-frequency roll-off filters. When I'm mixing live program material, whether music or speech, I ALWAYS use a good high pass filter on every microphone preamplifier. With most musical instruments, it's set near 200 Hz. With instruments like a bass or bass guitar, I'll move it down to 40 Hz or so. 73, Jim Brown K9YC ___ 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: [K3] [Elecraft] Rx/Tx equalization band selection
Low order distortion -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jim Brown Sent: Sunday, August 24, 2008 6:28 PM To: Barry N1EU; elecraft@mailman.qth.net Subject: Re: [K3] [Elecraft] Rx/Tx equalization band selection On Sun, 24 Aug 2008 14:41:54 -0700 (PDT), Barry N1EU wrote: Why is 50hz important if it is completely outside the passband? +/-16dB at 50hz has zero effect on rx or tx in the K3. Don't be so sure that there's no effect. It's important that when this undesired low frequency energy is produced by the mic, it is not carried through AUDIO path where it can trigger limiting, create distortion, or even cause overload. On the air, especially during contests, I hear lots of low frequency trash on SSB signals, most of it room noise. In general, if the desired bandwidth of a system is limited, as ours is, the modulating signal (in this case, microphone audio) should be bandwidth- limited as early in the signal chain as practical. Many good mics have built-in high pass filters or low-frequency roll-off filters. When I'm mixing live program material, whether music or speech, I ALWAYS use a good high pass filter on every microphone preamplifier. With most musical instruments, it's set near 200 Hz. With instruments like a bass or bass guitar, I'll move it down to 40 Hz or so. 73, Jim Brown K9YC ___ 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
