Re: [Elecraft] K3: SSB - WPX - Filters - Controls
I also noted the splatter problem - as well as the poor operators who are unable to listen properly (a station in Singapore) vs the good ones (an Italian) who can. I think the reason for this close in rejection problem might be the shape factor of the DSP. In my case, it was not spatter as we normally think of it, but just getting rid of the adjacent channel without seriously compromising the wanted channel. My K3 is worse in shape than my IC7400 but it depends on whether or not you use narrow or sharp mode of the IC7400. Luckily, I can install new firmware in the K3. I am sure shape factor adjustment is in the pipeline - or even already there but missed by me. The IC7400 is also a DSP based radio, but I have not seen any options to update the firmware. DSP is the place to fix this - I see no point at all in buying a 1.8kHz filter for SSB , it is just not necessary. If there is a signal 2kHz away inside the 2.7 but outside the 1.8 and 100dB above noise you are going to have problems with their IMDs anyway. No filter is going to help if the adjacent station is transmitting a wide signal. NR is not helpful towards copying weak signals amongst strong QRM. That is not what it is for and you should be able to do much better without it than with it. NR comes into its own when the band is not so crowded but is noisy. -- View this message in context: http://www.nabble.com/K3%3A--SSB---WPX---Filters---Controls-tp16399464p16418717.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] K3: SSB - WPX - Filters - Controls
I see no point at all in buying a 1.8kHz filter for SSB , it is just not necessary. If there is a signal 2kHz away inside the 2.7 but outside the 1.8 and 100dB above noise you are going to have problems with their IMDs anyway. Few people will benefit from narrow SSB filters, but no point at all is going too far. The 1.8kHz crystal filter is very effective for strong signals in its stopband but still within the passband of a 2.7kHz filter, e.g., a clean SSB signal 3kHz away. For most situations the additional 900Hz of IMD protection is not needed, but it is quite useful for serious contesters trying to keep the rate up on crowded bands. 73, Ed - W0YK ___ 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] K3: SSB - WPX - Filters - Controls
In crowded band conditions, narrow filtering is often helpful. In particular, for SSB contests, a receive bandwidth of 1500-1800Hz is very effective. For me, 1500Hz (300-1800Hz) works great on the K3. There is no intelligibility above 1800Hz that is useful in a contest QSO. If you think 200-2000Hz is easier to copy (1.8kHz bandwidth), then use that. But there is no reason to use a 2.7 or 2.8kHz filter in a contest and letting in another kHz or so of QRM. Depending on preference some people like to narrow their SSB bandwidth by using a combination of WIDTH and SHIFT. I prefer to simply reduce HI CUT because the high audio frequencies (2000-3000Hz) are the least useful in contest communication. So, it is a simple one-knob adjustment to narrow the SSB bandwidth on receive. You can select these narrow bandwidths with the K3 DSP and the stock 2.7kHz crystal filter. You don't need narrow crystal filters unless you also want protection from splatter and signal components from nearby strong signals that fall between the bandwidth of the 2.7kHz filter and whatever narrower crystal filter, e.g., 1.8kHz, you might use. 73, Ed - W0YK During my first foray into SSB Contesting with the K3 during WPX, I found that I need either: 1. Understand more about the DSP and the controls for BW, Hcut and Lcut 2. Obtain a narrower roofing filter for SSB - like a 1.8 Khz filter 3. Or both. I spent some time trying to find the sweet spot in the radio for SSB using the 2.8 Khz filter. I don't think I found it. At least, I am not satisfied. I tried narrowing up the filter bandwidth to 2.4 or 2.2some times 1.8. I tried shifting it up and down the bandpass. I tried to use High Cut and Low Cut depending on where the offending signal was coming from. AGC was on Slow with the standard settings. Used the RIT a lot It seemed I was always fighting some sort of side band splatter or stations close in on the frequency. Maybe it was just a crowded 20 meter band, but the same things happened on 40 meters. Do I need to go to a 1.8 Khz filter to give the DSP a break? Do I need to understand and play with the RX more to make sure I am doing it right. ___ 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] K3: SSB - WPX - Filters - Controls
Why a 1.8 filter? Well put Ed-W0YK. I am no electrical engineer, ie have no electronics background, but I do my best to understand. In addition to what Ed-W0YK mentioned there are at least a few more situations besides contests for a 1.8 filter on receive for SSB. I have been on the bands everyday working a lot of DX and I note the RTTY and CW and SSB DX stations are more and more going to split frequency. Many are just saying UP and many are saying up 1 and many SSB stations are just saying up. I have no problem with this as it is best if the DX station does not use anymore bandwidth than possible operating split. I can see why they go split as simplex can be a real mess. The point is calling stations are really getting close to the listening(DX)frequency. As we move into a season of more sporadic E(can really be strong) on the higher bands calling stations this close are going to be a problem as they will be much louder than they are now. With hopefully more sunspots down the road F2 signals more local will be very loud on 17M and up. Even now on 20 meters and down they already often are loud so we need all the IMD protection we can get. The l.8 filter roofing filter with DSP can make a difference. On CW, RTTY and SSB I think a number of people lose track how close they are getting to the DX station and I often have stations on CW and RTTY calling with in 300-500 hz and on SSB with in 1000 hz. What makes this especially bad is they can call that close for a long time as they don't get worked by the DX station. Having operated a number of DX-Peditions I always made sure not to work anyone real close to my frequency and I note others do the same to prevent station getting almost on top of the DX stations frequency. Sometimes the calling stations figure it out that they are to close and sometimes the policeman get them moved(not easy as they often are not listening to their transmit frequency) but then you have the policeman QRM. Another thing that happens quite commonly is two DX stations with the one having a listening frequency range that includes or gets extremely close to the other DX stations frequency. A second reason is a DX station operating split often accidentally gets TRASHED by a very close station(usually does not know the DX station is there) 1 or 2 Khz away or right on top of them and then there are the Policeman trying to get them to move. It can be difficult to copy a DX station even with reasonable strength when this happens. Obviously if they are right on top there is nothing we can do with the rcv but often they are not right on the frequency and the rcv comes into play. A third possible reason that I am interested in finding out about under actual operation is combating QRN on SSB with 1.8 and the proper AGC vs a wider filter and the proper AGC. I think this somewhat depends on the hearing from person to person but there is a lot of difference between 2.7 to 1.8 in filter width. This would mainly apply to 80 and 60 meters I would think as there is little SSB on 160M on the low end but could come into play higher in the band. I know from a lot of moonbounce experience a narrower filter often helped as long as it was not to narrow. A fourth reason which has often been mentioned is if you have hams that live close to you! Admittedly they are not likely to operate that close to you normally that the difference in filters would make any difference but you both might want to chase the same DX station at the same time as sometimes the window to a rare one is just 10 or 15 minutes a day and the DX station is just listening in a narrow range up a little. In this situation the other station can be pinning your meter so you need all the help you can get! Fifth even if you don't work DX or Contest but have any schedules or just get on and call CQ and ragchew so often even after asking several times if the frequency is in use some one can get very close to you and also band conditions change. Also if you like nets it is not at all unusual to have a very strong station interfering with NCS and other stations on frequency. Maybe it is because I live in the middle of the country but QRM very close in frequency is a constant issue for me; especially on SSB no matter what type of operation I am doing. Obviously as W0YK said it depends on what type of operating you do. If you only do cw, digital and rarely if ever get on SSB then the 1.8 filter is not needed. If you get on SSB much at all to me it seems to make economic sense to eventually get a 1.8 or 2.1 filter for receive given we are not talking about a lot of money difference, maybe 4% -7% of the total price. IMHO on SSB receive the major advantage a K3 has over any other radio on the market would be the narrower roofing filter than the competition. The only other advantages I can see on SSB over others might be a more effective NR/NB but of course
Re: [Elecraft] K3: SSB - WPX - Filters - Controls
Why a 1.8 kHz filter? Despite the belief that DSP can accomplish all things, it's not necessarily true. After experimenting around with only the 2.8 kHz filter for SSB, I decided that I didn't like the way the DSP version of the 1.8 kHz bandwidth sounded; it had a slight ringiness to it. I ordered a 1.8 filter on a Thursday afternoon, and it was in my mailbox on Monday. The sound was definitely more pleasant to my ears. Remember - we are analog beings, not digital. 73, Steve NN4X ___ 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] K3: SSB - WPX - Filters - Controls
I would like to make a few comments and ask some questions. This is by no means a put-down of the the K3, because I am not sure I am operating the rig correctly. After all it is a SDR and it is new. During my first foray into SSB Contesting with the K3 during WPX, I found that I need either: 1. Understand more about the DSP and the controls for BW, Hcut and Lcut 2. Obtain a narrower roofing filter for SSB - like a 1.8 Khz filter 3. Or both. I spent some time trying to find the sweet spot in the radio for SSB using the 2.8 Khz filter. I don't think I found it. At least, I am not satisfied. I tried narrowing up the filter bandwidth to 2.4 or 2.2some times 1.8. I tried shifting it up and down the bandpass. I tried to use High Cut and Low Cut depending on where the offending signal was coming from. AGC was on Slow with the standard settings. Used the RIT a lot It seemed I was always fighting some sort of side band splatter or stations close in on the frequency. Maybe it was just a crowded 20 meter band, but the same things happened on 40 meters. Do I need to go to a 1.8 Khz filter to give the DSP a break? Do I need to understand and play with the RX more to make sure I am doing it right. I would like to some feedback and comments on how other people set up their K3s for SSB contesting. I want to learn more about this radio. Lee - K0WA In our day and age it seems that Common Sense is in short supply. If you don't have any Common Sense - get some Common Sense and use it. If you can't find any Common Sense, ask for help from somebody who has some Common Sense. Is Common Sense divine? ___ 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] K3: SSB - WPX - Filters - Controls
I have made 700 QSO's in WPX SSB contest(part time). I have also tried different adjustment on the K3 including RX EQ. I have to say the same thing It seemed I was always fighting some sort of side band splatter or stations close in on the frequency. Splatter is always in the contest but not as pronounced as with K3. I don't know if it is the freq. response or something else with DSP. I was so tired after few hundred QSO's. I have switched to TS930S. With TS930s it was much better. Signals were much cleaner more dynamic and the splatter not as offending as with K3. I have 2.7kHz filter in my K3. I like K3 very much in CW CONTEST but don't like in SSB contest at all. Also, for some reason the output power from the K3 was fluctuating in time. I had to keep adjusting PWR. My alpha 87A was showing 1500W PEP and than about 900W and so on. Than after 10 second or so again 1500W. Looked to me like ALC action in the K3 was not always the same. I don't connect ALC to the amp. Same thing when I switched to IC-4KL amp. Mark --- On Mon, 3/31/08, Lee Buller [EMAIL PROTECTED] wrote: From: Lee Buller [EMAIL PROTECTED] Subject: [Elecraft] K3: SSB - WPX - Filters - Controls To: Elecraft Reflector elecraft@mailman.qth.net Date: Monday, March 31, 2008, 6:31 AM I would like to make a few comments and ask some questions. This is by no means a put-down of the the K3, because I am not sure I am operating the rig correctly. After all it is a SDR and it is new. During my first foray into SSB Contesting with the K3 during WPX, I found that I need either: 1. Understand more about the DSP and the controls for BW, Hcut and Lcut 2. Obtain a narrower roofing filter for SSB - like a 1.8 Khz filter 3. Or both. I spent some time trying to find the sweet spot in the radio for SSB using the 2.8 Khz filter. I don't think I found it. At least, I am not satisfied. I tried narrowing up the filter bandwidth to 2.4 or 2.2some times 1.8. I tried shifting it up and down the bandpass. I tried to use High Cut and Low Cut depending on where the offending signal was coming from. AGC was on Slow with the standard settings. Used the RIT a lot It seemed I was always fighting some sort of side band splatter or stations close in on the frequency. Maybe it was just a crowded 20 meter band, but the same things happened on 40 meters. Do I need to go to a 1.8 Khz filter to give the DSP a break? Do I need to understand and play with the RX more to make sure I am doing it right. I would like to some feedback and comments on how other people set up their K3s for SSB contesting. I want to learn more about this radio. Lee - K0WA In our day and age it seems that Common Sense is in short supply. If you don't have any Common Sense - get some Common Sense and use it. If you can't find any Common Sense, ask for help from somebody who has some Common Sense. Is Common Sense divine? ___ 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 OMG, Sweet deal for Yahoo! users/friends:Get A Month of Blockbuster Total Access, No Cost. W00t http://tc.deals.yahoo.com/tc/blockbuster/text2.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] K3: SSB - WPX - Filters - Controls
Lee, The WPX contest was an interesting experience with the K3. I was working 670 contacts in single op all band non assisted high pwr mode. I am not a very experienced contester, but I have been working a number of SSB contests with my MP over the past 2-3 years. My impression of the K3 is similar to what you and Mark Roz describe. First I thought it was the headphones but soon I realized that the radio sounds a little different that I am used to. Some high pitched audio appeared very sharp, and less filtered than I am used to and splatter was hard to fight. I was normally starting with a 2.4 kc bandwidth, working my way down below 2 kc when there was a lot of splatter. I also noticed that I had to center the passband very low in most cases to dig out the signal. That seemed a little different depending on the spectrum energy in the received signal, but most often my passband was tuned very low for best receive. After the WPX experience I am now willing to try a sharper SSB filer, I think it is needed. I also tried noise reduction as higher bands sometimes where very noisy and signals weak. For me, DSP NR never really worked well. The NR in the K3 seems to do a pretty nice job, but still my brain is far better. I have also noticed the fluctuation in output, not being sure if it was my low band antennas rocking in the wind or something else. I read Sunday about some SSB issues in the current firmware release, so they might be dealt with soon. Unfortunately I updated my firmware right before the contest. On the positive note I have to say that the K3 is well thought trough. I feel comfortable with the physical layout and the radio is very easy to operate. Most of the time I used the filters in shift/width mode, not LO/HI and sometimes I was running with AGC off using RF-gain instead. Would be interesting to hear others experience. With 600 radios out there, there should be quite a few that's been exercised this weekend. 73 de Björn /SM0MDG 7S0X On 080331 15:31 , Lee Buller [EMAIL PROTECTED] wrote: I would like to make a few comments and ask some questions. This is by no means a put-down of the the K3, because I am not sure I am operating the rig correctly. After all it is a SDR and it is new. During my first foray into SSB Contesting with the K3 during WPX, I found that I need either: 1. Understand more about the DSP and the controls for BW, Hcut and Lcut 2. Obtain a narrower roofing filter for SSB - like a 1.8 Khz filter 3. Or both. I spent some time trying to find the sweet spot in the radio for SSB using the 2.8 Khz filter. I don't think I found it. At least, I am not satisfied. I tried narrowing up the filter bandwidth to 2.4 or 2.2some times 1.8. I tried shifting it up and down the bandpass. I tried to use High Cut and Low Cut depending on where the offending signal was coming from. AGC was on Slow with the standard settings. Used the RIT a lot It seemed I was always fighting some sort of side band splatter or stations close in on the frequency. Maybe it was just a crowded 20 meter band, but the same things happened on 40 meters. Do I need to go to a 1.8 Khz filter to give the DSP a break? Do I need to understand and play with the RX more to make sure I am doing it right. I would like to some feedback and comments on how other people set up their K3s for SSB contesting. I want to learn more about this radio. Lee - K0WA ___ 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] K3: SSB - WPX - Filters - Controls
FWIW, I run two SSB filters - 2.7 and 1.8 KHz. I find the 2.7 is fine for ragchewing and light (no crowds) DXing and contesting. I can also vouch for the 1.8 KHz roofing filter. It *kills* sidesplatter, esp. when used judiciously with the DSP to clean up the passband edges. I plan to substitute the 2.8 8-pole for the 2.7 one of these days, but it's not a priority. Eventually, you get used to pulling down the Hi Cut to rub out high freq chatter. The 1.8 and DSP together are a very powerful combination. Also, FWIW - the human brain is The Ultimate Filter. NR can only help compensate for its front-end input. That being said, the K3's NR is the best I've heard in my limited 37-year ham experience. 73, matt, W6NIA K3 # 24 Lee, snip After the WPX experience I am now willing to try a sharper SSB filer, I think it is needed. I also tried noise reduction as higher bands sometimes where very noisy and signals weak. For me, DSP NR never really worked well. The NR in the K3 seems to do a pretty nice job, but still my brain is far better. snip - back to Lee's original post Do I need to go to a 1.8 Khz filter to give the DSP a break? Do I need to understand and play with the RX more to make sure I am doing it right. I would like to some feedback and comments on how other people set up their K3s for SSB contesting. I want to learn more about this radio. Lee - K0WA ___ 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
