Re: [Elecraft] Re: K1 on USB CW
N2EY said: The bigger point, and the reason for all the bandwidth, is that we do ourselves and amateur radio a disservice if we blindly accept such stories without checking out the facts. The difference between high side low side injection is something I'm always having to explain over over again to satellite equipment vendors who should really be the ones that have to explain it to their customers - so not surprising to see spectrum perversion throwing a googlie at amateurs. 73, VR2BrettGraham ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
3) The filter system lent itself easily to transceiver implementations. This greatly reduced size, power consumption, cost and complexity, because the same oscillators could be used for both transmit and receive. Also, the task of zeroing the transmitter was mostly eliminated. (Trivia: what was the *first* manufactured HF SSB amateur transceiver?) The earliest I can recall was the Collins KWM-1, introduced in 1957, but I suspect that may not be the correct answer. Transceivers of any sort were not common in the mid-1950s. My high school principal (K6AHL) had the first SSB setup I ever saw, a Collins KWS-1 transmitter with the matching 75A4 receiver, circa 1955. -- Bob Nielsen, N7XY n7xy (at) n7xy.net Bainbridge Island, WA http://www.n7xy.net ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
[Elecraft] Re: K1 on USB CW
Steve WB6RSE wrote: Anyone have any experience changing the K1 from LSB to USB CW? Steve, That's an interesting question. The K1 front end mixer injects the local oscillator (LO) signal ABOVE the incoming RF signal (high side injection), while the product detector injects the BFO signal BELOW the IF signal (low side injection). The result is the receiver functioning in LSB mode. One could raise the frequency of the BFO so that it is above the IF signal (high side injection), and you would have as a result a receiver operating in USB mode. The *only* positive attribute of going to high side BFO injection that I can think of would be a theoretical improvement in opposite sideband rejection due to the asymetrical shape of the IF crystal filter bandpass skirts. But the opposite sideband rejection of the K1 is already as good as one will ever need. The big negative to USB for me would be losing the ability to copy LSB phone on the lower 20 kHz of the 40m phone band on my K1 with a 170 kHz VFO span. One finds no USB signal worth covering on 30m unless it is military/utility outside the ham band, and nothing on 17m or 15m on USB within the K1 tuning range, nor are the foreign phone USB signals on 20m of much interest to me. The other operating characteristic that would change is that the AF tone of the received signal would lower as the VFO is tuned upward in USB mode. I like the LSB characteristic of the AF tone going up as I tune upward on the VFO. I'd be curious about the advantages that you see in a K1 LSB-to-USB conversion. 73, Mike / KK5F ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
On Jun 17, 2004, at 10:43 AM, Mike Morrow wrote: I'd be curious about the advantages that you see in a K1 LSB-to-USB conversion. 73, Mike / KK5F Mike - I have no interest in listening to SSB with the K1 and have set it up for an 80 kc spread. The advantage to USB CW is that it has long been the standard for CW - even on 160-80-40 where sideband operation is LSB - CW is still USB. I usually start tuning from the bottom end of the band going up and it is often useful to hear what's up the band as you tune higher. For casual operation, it is not that big a deal but in chasing DX it is nice hear the split up frequency. With LSB you would hear the last station worked only if he was below your listening frequency rather than above, especially if the signal is weak. For serious DX chasing, USB CW is the way to go. That said, the K1 is a very impressive design with clever mechanical assembly features and carefully thought out ergonomics. Wayne and Eric really know their stuff. By-the-way: The present day LSB - USB band standards have their roots from years ago in the availability of 9 Mc crystals / filters - when SSB was experimental and you had to build your own. 9 Mc plus a VFO running at 5.0 to 5.5 Mc gives you 20m USB. Subtract the VFO frequency and you tune backwards on 75/80m and you get LSB. There is actually no reason for USB vs LSB on any band anymore. It's just convention from the original experimental designs. 20m and above is USB, below 20m it's LSB. You'll occasionally hear some DX on 20m on LSB to keep the crowd away. I'd be interested in anyone's attempts at shifting the K1 to USB CW. 73, Steve WB6RSE ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
To solve this problem see my SSB mods for K1 and see only the schematic part regarding BFO . Documentation to my web page: http://it.geocities.com/giulianoi0cg/k1_page.html 73 de Giuliano I0CG Steve WB6RSE wrote: Anyone have any experience changing the K1 from LSB to USB CW? ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
In a message dated 6/17/04 2:41:52 PM Eastern Daylight Time, [EMAIL PROTECTED] writes: The present day LSB - USB band standards have their roots from years ago in the availability of 9 Mc crystals / filters - when SSB was experimental and you had to build your own. 9 Mc plus a VFO running at 5.0 to 5.5 Mc gives you 20m USB. Subtract the VFO frequency and you tune backwards on 75/80m and you get LSB. No, that's just not true. Urban legend. I believed it for years but when I did the math the truth could not be denied. The only way you get sideband inversion is if the heterodyne oscillator is above *both* the input and output frequencies of a mixing process. Yes, the 9 MHz IF / 5-5.5 Mhz VFO scheme was popular, and it does result in one band tuning backwards. But it *does not* result in sideband inversion! Generate USB and 9 MHz and mix it with a 5-5.5 MHz VFO and you get USB on 75 and 20. The LSB/USB convention for hams goes back to before hams used 9 MHz filters to generate SSB. . Now if you use a 5 MHz SSB generator and a 9 MHz VFO you *do* get sideband inversion. If anyone wants the exact math, I have it all written up. 73 de Jim, N2EY ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
I just picked up a copy of the June CQ in the airport bookshop and p.28 has a sidebar by K2MGA (CQ Publisher) on the history of SSB: Regardless of how the SSB signal was generated, the 455 kc USB signal was mixed up to 9 Mc. Using a converted war-surplus BC-458 transmitter...as a VFO, the 4.0 to 5.3 Mc output was either added to or subtracted from the 9Mc SSB signal. That produced a USB signal on 20 meters or an LSB signal on 75 meters. (That's the origin of the world-wide convention: LSB below 20 meters; USB on 20 meters and up. ..) On Thu, 17 Jun 2004 5:37pm, [EMAIL PROTECTED] wrote: No, that's just not true. Urban legend. ... Now if you use a 5 MHz SSB generator and a 9 MHz VFO you *do* get sideband inversion. 73, WA5ZNU Leigh ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
Leigh L. Klotz, Jr. wrote: I just picked up a copy of the June CQ in the airport bookshop and p.28 has a sidebar by K2MGA (CQ Publisher) on the history of SSB: Regardless of how the SSB signal was generated, the 455 kc USB signal was mixed up to 9 Mc. Using a converted war-surplus BC-458 transmitter...as a VFO, the 4.0 to 5.3 Mc output was either added to or subtracted from the 9Mc SSB signal. That produced a USB signal on 20 meters or an LSB signal on 75 meters. This is just wrong. Say you generate a USB signal at 9 MHz from a 1 KHz audio tone. The (suppressed) carrier of the generated USB signal is at 9.000 MHz and the upper sideband is at 9.001 Mhz. Then mixing with a 5.0 MHz VFO would give sum frequencies of 14.000 and 14.001 MHz as well as differences of 4.000 and 4.001 MHz. This is USB in both cases. Of course, the VFO would tune in opposite directions. Even a CW operator like me can add and subtract! -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
As I read it, the USB signal was generated at 455Kc and then mixed up to 9Mc, thus giving a USB 9Mc signal. The VFO was then in thr 4.0-5.3Mc range. And that was added or subtracted... On Thu, 17 Jun 2004 8:02pm, Vic Rosenthal wrote: Leigh L. Klotz, Jr. wrote: I just picked up a copy of the June CQ in the airport bookshop and p.28 has a sidebar by K2MGA (CQ Publisher) on the history of SSB: Regardless of how the SSB signal was generated, the 455 kc USB signal was mixed up to 9 Mc. Using a converted war-surplus BC-458 transmitter...as a VFO, the 4.0 to 5.3 Mc output was either added to or subtracted from the 9Mc SSB signal. That produced a USB signal on 20 meters or an LSB signal on 75 meters. This is just wrong. Say you generate a USB signal at 9 MHz from a 1 KHz audio tone. The (suppressed) carrier of the generated USB signal is at 9.000 MHz and the upper sideband is at 9.001 Mhz. Then mixing with a 5.0 MHz VFO would give sum frequencies of 14.000 and 14.001 MHz as well as differences of 4.000 and 4.001 MHz. This is USB in both cases. Of course, the VFO would tune in opposite directions. Even a CW operator like me can add and subtract! -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com 73, WA5ZNU Leigh ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
Vic - As I recall from about a million years ago, when the hardware was actually built, when you subtracted to get to 75m, the sideband reversed. If not, the standard on 160-80-40 today would be USB - but it isn't. 73, Steve WB6RSE On Jun 17, 2004, at 4:59 PM, Vic Rosenthal wrote: This is just wrong. Say you generate a USB signal at 9 MHz from a 1 KHz audio tone. The (suppressed) carrier of the generated USB signal is at 9.000 MHz and the upper sideband is at 9.001 Mhz. Then mixing with a 5.0 MHz VFO would give sum frequencies of 14.000 and 14.001 MHz as well as differences of 4.000 and 4.001 MHz. This is USB in both cases. Of course, the VFO would tune in opposite directions. Even a CW operator like me can add and subtract! -- 73, Vic, K2VCO Fresno CA ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
I just looked at my old copy of the NEW Sideband Handbook by Don Stoner W6TNS, copyright 1958 - I have 6th printing dated June 1966. Page 94 shows the schematic of the Central Electronics 10B phasing exciter - and it DOES generate SSB at a fixed 9 MHz (unchanged from the 10A). The addition of a 5 to 5.5 MHz VFO will allow it to cover both 75 and 20 meters. I do recall conversations among SSB ops about the sideband selection for the various bands, but I cannot recall the details. For many years, I thought the sidebands were flipped between 75 and 20 meters with this 9 MHz generator and the 5 to 5.5 MHz VFO, but then I saw the math which says the sidebands did NOT flip with this mixing scheme - Oh well, the conventions are well glued in place - who will be real pioneers and campaign to get everyones mindset changed? Anyone for no QSOs? G 73, Don W3FPR Life is what happens when you are making other plans - Original Message - It goes back to the original SSB Jr. which was ultimately the basis for the FIRST real commercially built SSB transmitter, the Central Electronics 10A. It was a phasing rig and, the SSB selector was simply labeled SB1 and SB2. Since 75 and 20 were the popular bands then for SSB (there wasn't a 40 meter phone band back then!) the operators were lazy and used the SB1 position for both bands (as I remember) yielding LSB for 75 and USB for 20. Commercially and on the marine bands, USB has been the standard since day 1 and far as I know. Why the amateurs have hung onto this old LSB on 40 and below thing I don't know. I forget whether the 10A/10B/20A used a 5 or a 9 mhz channel for SSB generation, but it DID flop over when you went from 20 to 75 meters! Must have been generating SSB at 5 Mhz. Anyhow that IS how that LSB/USB phenomenon got started: just plain laziness! Maybe one day they will mandate USB as the normal sideband? Didn't they state that on the 60 meter channels? (USB only?) I'm sure that was to get around the stupidity of the monitoring personnel who obviously used receivers with USB filters only and they didn't know CW! I thought it was a stupid move to channelize the 60 meter band on SSB only!!! I supposed ARRL has too many irons in the fire now with the rehashing of the amateur classes/privileges and BPL to worry about 60 meter mode expansion? ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
Re: [Elecraft] Re: K1 on USB CW
In a message dated 6/17/04 7:10:03 PM Eastern Daylight Time, [EMAIL PROTECTED] writes: I just picked up a copy of the June CQ in the airport bookshop and p.28 has a sidebar by K2MGA (CQ Publisher) on the history of SSB: Regardless of how the SSB signal was generated, the 455 kc USB signal was mixed up to 9 Mc. Using a converted war-surplus BC-458 transmitter...as a VFO, the 4.0 to 5.3 Mc output was either added to or subtracted from the 9Mc SSB signal. That produced a USB signal on 20 meters or an LSB signal on 75 meters. (That's the origin of the world-wide convention: LSB below 20 meters; USB on 20 meters and up. ..) I'm sorry, but that's simply not what happens. K2MGA is mistaken. Here's proof: The tuning reverses. But the sideband does not! Here's why: 9 MHz filter and 5-5.5 MHz VFO Start with a 9000 kHz USB signal (carrier at 9000, top end of audio at 9003) Add a 5200 kHz VFO signal for 20 meters (9000 + 5200 = 14200, 9003 + 5200 = 14203) Result is carrier at 14200, top end at 14203 - still USB Subtract a 5200 kHz VFO signal for 75 meters (9000 - 5200 = 3800, 9003 - 3800 = 3803) Result is carrier at 3800, top end at 3803 - still USB! The numbers tell the story. In order to cause sideband inversion, the local oscillator must be above *both* the input and output frequencies of the mixer. However: 5.2 MHz filter and 8.7 - 9.2 MHz VFO: Start with a 5200 kHz USB signal (carrier at 5200, top end at 5203) Add a 9000 kHz VFO signal for 20 meters Result is carrier at 14200, top end at 14203 - still USB Subtract the 5200 kHz USB signal from a 9000 kHz VFO signal for 75 meters (9000 VFO - 5200 carrier = 3800, 9000 VFO - 5203 top end = 3797) Result is carrier at 3800, top end at 3797 - now it's LSB! On Thu, 17 Jun 2004 5:37pm, [EMAIL PROTECTED] wrote: No, that's just not true. Urban legend. ... Now if you use a 5 MHz SSB generator and a 9 MHz VFO you *do* get sideband inversion. Do the math and you'll see that the old urban legend is a myth. The standard of LSB/USB in ham radio was set at the very beginning - 1949 at the latest. I wish it *were* true about the 5 MHz VFO/9 MHz IF sideband inversion - it would make some projects simpler! But the numbers don't lie. Check out the heterodyne scheme of the K2 and you'll see the same principles in action. The only way you get sideband (not tuning direction!) inversion is if the LO is higher than both the input and output frequencies of a mixer. 73 de Jim, N2EY
Re: [Elecraft] Re: K1 on USB CW
I mis remembered, it was a 9 MHz VFO in the radio I described, the one from ZL1AAX, apparently. Thanks math gurus. 73 Stuart
