> Just to make sure I understand you, the AM filter is only > required if one desires to transmit in AM or use ESSB. > Otherwise, AM reception like SW can still be piped through > the 13KHz FM filter?
Correct, I use the FM filter for listening to AM broadcast or SWL on a fairly regular basis. > How does the audio of AM SW sound going through the FM > filter? Bandwidth is obviously wider, so I'm assuming > higher fidelity? Somewhat higher fidelity. The K3's DSP has a fairly sharp cutoff at 4200 Hz so you will never get more than that but the FM filter allows the full 4.5 KHz where the AM filter starts to roll off at 3 KHz but still has some audio response down the filter skirts. I hope that someday Elecraft will "open up" the audio in AM so we can hear 5.5 or 6 KHz which as good as it gets these days. The whole point is that most of the other up conversion radios have 20 or even 30 KHz wide first IF filters. There's not much reason to deal with both the FM and AM filters ... most AM work is not that critical with regard to bandwidth at the first IF. The DSP sets the ultimate response in any case. 73, ... Joe, W4TV > -----Original Message----- > From: James Sarte [mailto:kc2...@gmail.com] > Sent: Tuesday, February 10, 2009 9:17 PM > To: li...@subich.com; 'KC2UEE'; 'Rick Tavan N6XI' > Cc: elecraft@mailman.qth.net > Subject: RE: [Elecraft] K3 sub-receiver usefulness? > > > Hi Joe, > > Just to make sure I understand you, the AM filter is only > required if one desires to transmit in AM or use ESSB. > Otherwise, AM reception like SW can still be piped through > the 13KHz FM filter? > > How does the audio of AM SW sound going through the FM > filter? Bandwidth is obviously wider, so I'm assuming higher > fidelity? > > 73, > James KC2UEE > > -----Original Message----- > From: Joe Subich, W4TV [mailto:li...@subich.com] > Sent: Tuesday, February 10, 2009 7:40 PM > To: 'KC2UEE'; 'Rick Tavan N6XI' > Cc: elecraft@mailman.qth.net > Subject: RE: [Elecraft] K3 sub-receiver usefulness? > > > > As for the 6KHz AM filter, to my understanding In order to > > receive and transmit AM, I will need this filter for sure. > > Just not sure how many I'll need, now that I only plan to > > purchase one general coverage module. > > No, you only need the AM filter if you plan to TRANSMIT AM > or ESSB and then only because Elecraft will not enable AM > and ESSB transmit with the FM filter. > > I would specifically not bother with the AM filter in the > subreceiver - nor would I get the FM filter for the subRX > unless I were also adding the general coverage front-end > filter. > > If Elecraft would enable AM and ESSB transmit with the FM > filter, my suggestions would be FM, 2.7, 400 and 200 in the > main receiver with FM, 2.7 and 400 in the subreceiver. A > 1.5 or 1.8 KHz narrow SSB filter can be added later if you > feel the need for a high performance option for contesting. > > 73, > > ... Joe, W4TV > > > > > -----Original Message----- > > From: elecraft-boun...@mailman.qth.net > > [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of KC2UEE > > Sent: Tuesday, February 10, 2009 5:48 PM > > To: Rick Tavan N6XI > > Cc: elecraft@mailman.qth.net > > Subject: Re: [Elecraft] K3 sub-receiver usefulness? > > > > > > Thank you Rick for your insight. I'll look closer into my > > filter and module choices, and perhaps save a bit of money in > > the process. > > > > After looking at the filter plots (didn't see any for the > > 5-poles though), I'll probably end up with the following: > > > > 13KHz FM filter - main only (will use for 10m FM transmit > > also) 6KHz AM filter - (I'm tempted to buy 2, one for the > > main and one for the sub... I'll probably put the gen > > coverage module in the sub) 2.7KHz 5-pole; 1 in the main and > > 1 in the sub. 500 Hz 5 pole - main only 250 Hz 8 pole - main only > > > > I'm mostly a SSB and 10m FM guy (local repeaters), but also > > do a bit of PSK31 and RTTY when the mood strikes me. How > > does this arrangement sound at present? As for the 6KHz AM > > filter, to my understanding In order to receive and transmit > > AM, I will need this filter for sure. Just not sure how many > > I'll need, now that I only plan to purchase one general > > coverage module. I'm not really sure which receiver would be > > best suited for general coverage as well. > > > > 73, > > James KC2UEE > > > > > > > > On Tue, Feb 10, 2009 at 4:59 PM, Rick Tavan N6XI > > <rta...@gmail.com> wrote: > > > With only one receiver you can only hear one band at a > > time. With the > > > new firmware, however, you can set the two VFOs to > > different bands and > > > flip between them using the A/B switch. I don't think > > cross-band SPLIT > > > will be available at first, if ever. > > > > > > I use my sub-rx to monitor both a DX station and its split > > frequency > > > pileup at the same time. Many others are using it for diversity > > > reception with two antennas. I plan to do that once I > have a better > > > filter complement. > > > > > > Unless you plan to listen to two broadcast stations at the > > same time, > > > I don't see any reason to put a general coverage bandpass > filter in > > > both receivers. Put one in the one receiver you intend to use for > > > SWLing. > > > > > > I don't think it's prudent to have both the 250 and 400 > Hz filters. > > > The actual width of the 250 is wider and the actual width > > of the 400 > > > is narrower so the two end up being very close to each other. If I > > > felt a need for something narrower than my 400, which I > > don't for my > > > operating, I would get the 200. The 250 and the 500 might > also be a > > > reasonable choice. > > > > > > I think the 200 is a tad narrow for 170 Hz RTTY but the 250 > > is fine. > > > However, I'm guessing as I have only a little RTTY experience. > > > > > > Unless you need to transmit AM, you probably don't need the > > 6 KHz. I > > > have one and it works fine but I'd just as soon use the 13 for AM > > > SWLing. I'll probably sell my 6. YMMV, especially if SWLing > > on a band > > > full of very loud BC stations (S9+40 +) is important to you. > > > > > > Unless you plan to do diversity reception on FM, you don't > > need two 13 > > > KHz filters. All transmitting is done through the filters > > on the main > > > board. > > > > > > If you want to operate SSB on crowded bands consider a 1.8 > > or 2.1 KHz > > > filter. > > > > > > GL & 73, > > > > > > /Rick N6XI > > > > > > On 2/9/09, James Sarte <kc2...@gmail.com> wrote: > > >> > > >> Hello group, > > >> > > >> > > >> > > >> Someone mentioned in one of the reflector emails that the new > > >> firmware under development will allow independent band > > >> switching/monitoring between VFO's without a sub receiver. Am I > > >> correct in my understanding then that without a sub > receiver, this > > >> firmware will allow tuning and monitoring of separate > > bands? If that > > >> is indeed the case, can someone please clarify for me > how that can > > >> accomplished with a single receiver? > > >> > > >> > > >> > > >> On a separate note, apart from diversity receive, I'm > > curious to know > > >> how other people are utilizing their sub receiver? The > > reason I ask > > >> is I'm finalizing my purchase of a K3, and am trying to determine > > >> whether it's necessary to fully load up both receivers > > now. At this > > >> point, I'm ready to purchase 2 general coverage modules > > plus 2 each > > >> of the following filters: 250KHz, 400KHz, 2.8Khz, 6KHz, > > 13KHz. I'd > > >> like to have the ability to monitor PSK31, FM or SW > > broadcast on the > > >> sub, while monitoring phone or engaging in a phone QSO on > > the main; > > >> both receivers being on separate bands. That's just one example. > > >> Another could be to monitor SW broadcast on the main while > > listening > > >> to 10m FM on the sub. Do I need to install the AM or FM > > filters in > > >> the sub to monitor SW or FM or can the sub's DSP take care of it? > > >> > > >> > > >> > > >> 73, > > >> > > >> James KC2UEE > > >> > > >> > > >> > > >> ______________________________________________________________ > > >> Elecraft mailing list > > >> Home: http://mailman.qth.net/mailman/listinfo/elecraft > > >> Help: http://mailman.qth.net/mmfaq.htm > > >> Post: mailto:Elecraft@mailman.qth.net > > >> > > >> 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:Elecraft@mailman.qth.net > > > > 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
