Re: [Elecraft] AGC Design of the K3
Cool. Nice to see logic reign for a change. -- View this message in context: http://www.nabble.com/AGC-Design-of-the-K3-tp17199520p17200646.html Sent from the Elecraft 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: [Elecraft] AGC Design of the K3
Very nice. Will this upgrade be able to be installed on older model K3s? -- View this message in context: http://www.nabble.com/AGC-Design-of-the-K3-tp17199520p17200418.html Sent from the Elecraft 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: [Elecraft] AGC Design of the K3
Wayne, I don't understand the concept of variable passband filters. Surely the K3 will just choose a filter based on the current operating frequency, and that filter will be used over a range of frequencies. How are these new filters you describe different? wayne burdick wrote: > > > > 3. Later this year we'll be offering variable-passband crystal filters > that each cover a significant bandwidth range, e.g. 200-400, 400-800, > etc. (These are not finalized.) Each of these filters will have 8 > discrete bandwidths. As you adjust the DSP controls, the K3 will again > optimize the passband of the selected filter. > > 73, > Wayne > N6KR > > -- View this message in context: http://www.nabble.com/AGC-Design-of-the-K3-tp17199520p17199832.html Sent from the Elecraft 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: [Elecraft] AGC Design of the K3
Thanks. -- View this message in context: http://www.nabble.com/AGC-Design-of-the-K3-tp17199520p17199788.html Sent from the Elecraft 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: [Elecraft] AGC Design of the K3
Thanks guys. -- View this message in context: http://www.nabble.com/AGC-Design-of-the-K3-tp17199520p17199766.html Sent from the Elecraft 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: [Elecraft] AGC Design of the K3
Shane White wrote: > > I noticed a remedy for the following problem on the K3 enhancement list - > > Hardware AGC threshold change > Some users prefer tuning the band with a wide filter bandwidth selected > (for example, using a 2.7 or 2.8 kHz SSB filter in CW mode rather than a > 500 Hz or narrower filter). Strong off-frequency signals (above about > S9+5) that are inside the crystal filter passband can then activate the > hardware AGC circuit, reducing the level of desired signals. > > Shouldn't a radio's AGC only use signals within the selected final IF > passband width to control gain? > No because the DSP stage doesn't have enough dynamic range to handle the full 140 dB range of possible input signals. There are two AGCs in the K3, Orion, etc...analog ahead of the DSP stage and digital within the DSP. The analog AGC ahead of the DSP is needed to protect the ADC from overload and the digital can then handle about 100 dB internally. 73, Bill W4ZV -- View this message in context: http://www.nabble.com/AGC-Design-of-the-K3-tp17199520p17199649.html Sent from the Elecraft 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
[Elecraft] AGC Design of the K3
I noticed a remedy for the following problem on the K3 enhancement list - Some users prefer tuning the band with a wide filter bandwidth selected (for example, using a 2.7 or 2.8 kHz SSB filter in CW mode rather than a 500 Hz or narrower filter). Strong off-frequency signals (above about S9+5) that are inside the crystal filter passband can then activate the hardware AGC circuit, reducing the level of desired signals. Shouldn't a radio's AGC only use signals within the selected final IF passband width to control gain? Wasn't this kind of AGC "pumping" described above a problem in older radios when DSP initially featured and the AGC wasn't included within the DSP functionality? That is, AGC would operate using circuitry prior to the DSP, users would then narrow the passband width using the DSP but then found that signals outside this passband would reduce the desired signal. -- View this message in context: http://www.nabble.com/AGC-Design-of-the-K3-tp17199520p17199520.html Sent from the Elecraft 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
