Re: [time-nuts] Why these Crystal Frequencies?
13.5 and 27 MHz are usually associated with digital video. SD video with 720 x 576 has a pixel clock of 13.5 MHz, and the corresponding SDI bit clock is 270 MHz. Cheers Stefan -Ursprüngliche Nachricht- Von: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] Im Auftrag von Brooke Clarke Gesendet: Donnerstag, 15. Dezember 2011 04:13 An: Discussion of precise time and frequency measurement Betreff: [time-nuts] Why these Crystal Frequencies? Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz 40.0 75.0 76.79 76.8 76.81 96.0 3.072 MHz 4.0 4.096 5.0 6.0 7.3729 8.0 8.192 9.8304 10.0 11.0 11.0592 11.2896 12.0 12.288 12.352 13.5 14.31818 15.36 16.0 16.384 17.734475 18.0 18.432 19.6608 19.44 22.1184 24.0 24.567 25.0 25.175 28.63636 30.0 1.4204058 GHz Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Peter Bell wrote: It's exactly 52 times the 1.2288MHz reference that IS95/CDMA2K uses - this may be a coincidence, but I somehow doubt it. Regards, Pete On Thu, Dec 15, 2011 at 3:46 AM, Joe Leikhimjleik...@leikhim.com wrote: I have been watching this thread and may have missed something. My questions: What is the purpose of the outboard OCXO VECTRON 63.8976Mhz? What model number does this RB most closely resemble? -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida www.Leikhim.com jleik...@leikhim.com 407-982-0446 Note to GMail Account users. Due to an abnormally high volume of spam originating from bogus GMail accounts, I have found it necessary to block certain GMail traffic. Please phone me if you believe your message was not received. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
SD-SDI 270MHz, then there is the HD-SDI. Brooke, the 77.503KHz you mention for the DCF77: are you sure the IF is 3KHz? 77.503KHz is 77.5KHz + 3Hz... On Thu, Dec 15, 2011 at 11:54 AM, Heinzmann, Stefan (ALC NetworX GmbH) stefan.heinzm...@alcnetworx.de wrote: 13.5 and 27 MHz are usually associated with digital video. SD video with 720 x 576 has a pixel clock of 13.5 MHz, and the corresponding SDI bit clock is 270 MHz. Cheers Stefan -Ursprüngliche Nachricht- Von: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] Im Auftrag von Brooke Clarke Gesendet: Donnerstag, 15. Dezember 2011 04:13 An: Discussion of precise time and frequency measurement Betreff: [time-nuts] Why these Crystal Frequencies? Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz 40.0 75.0 76.79 76.8 76.81 96.0 3.072 MHz 4.0 4.096 5.0 6.0 7.3729 8.0 8.192 9.8304 10.0 11.0 11.0592 11.2896 12.0 12.288 12.352 13.5 14.31818 15.36 16.0 16.384 17.734475 18.0 18.432 19.6608 19.44 22.1184 24.0 24.567 25.0 25.175 28.63636 30.0 1.4204058 GHz Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Peter Bell wrote: It's exactly 52 times the 1.2288MHz reference that IS95/CDMA2K uses - this may be a coincidence, but I somehow doubt it. Regards, Pete On Thu, Dec 15, 2011 at 3:46 AM, Joe Leikhimjleik...@leikhim.com wrote: I have been watching this thread and may have missed something. My questions: What is the purpose of the outboard OCXO VECTRON 63.8976Mhz? What model number does this RB most closely resemble? -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida www.Leikhim.com jleik...@leikhim.com 407-982-0446 Note to GMail Account users. Due to an abnormally high volume of spam originating from bogus GMail accounts, I have found it necessary to block certain GMail traffic. Please phone me if you believe your message was not received. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
19.44 This is a typical frequency used in IS-136 TDMA cellular handsets and possibly base stations. The value is 400 times the raw bit rate of the channel (48.6 kHz). Randy. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
16.384 MHz is of course 2^14 times 1 kHz. This was used as a clock for direct digital synthesizers in signal generators. Most DDS's can't generate exact frequencies starting from a 10 MHz clock. There was an Agilent arbitrary waveform generator that used this as a clock because circular memory has a binary length. The color burst frequency contains factors of 3,5,7,9, and 11, which are important in terms of how early TV station hardware worked, using multivibrator type frequency dividers. 11 is about the limit for those. Rick N6RK Brooke Clarke wrote: Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz 40.0 75.0 76.79 76.8 76.81 96.0 3.072 MHz 4.0 4.096 5.0 6.0 7.3729 8.0 8.192 9.8304 10.0 11.0 11.0592 11.2896 12.0 12.288 12.352 13.5 14.31818 15.36 16.0 16.384 17.734475 18.0 18.432 19.6608 19.44 22.1184 24.0 24.567 25.0 25.175 28.63636 30.0 1.4204058 GHz Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Peter Bell wrote: It's exactly 52 times the 1.2288MHz reference that IS95/CDMA2K uses - this may be a coincidence, but I somehow doubt it. Regards, Pete On Thu, Dec 15, 2011 at 3:46 AM, Joe Leikhimjleik...@leikhim.com wrote: I have been watching this thread and may have missed something. My questions: What is the purpose of the outboard OCXO VECTRON 63.8976Mhz? What model number does this RB most closely resemble? -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida www.Leikhim.com jleik...@leikhim.com 407-982-0446 Note to GMail Account users. Due to an abnormally high volume of spam originating from bogus GMail accounts, I have found it necessary to block certain GMail traffic. Please phone me if you believe your message was not received. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
On 12/15/2011 04:13 AM, Brooke Clarke wrote: Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 12.288 AES/EBU and S/P-DIF baud-rate for 96 kHz sampling-rate 128 x 96 kHz = 12,288 MHz Also in wide use for audio-boards. 6,144 MHZ 24,576 MHz is related multiples for 48 kHz and 192 kHz. 19.44 SDH/SONET STM-1 byte-rate 270*9*8 kHz = 19,44 MHz 51,84 MHz 155,52 MHz 311,04 MHz 622,08 MHz are related multiples that occurs regularly Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
On 12/15/2011 11:54 AM, Heinzmann, Stefan (ALC NetworX GmbH) wrote: 13.5 and 27 MHz are usually associated with digital video. SD video with 720 x 576 has a pixel clock of 13.5 MHz, and the corresponding SDI bit clock is 270 MHz. 18 MHz is another digital video frequency. 13,5 MHz is the sampling frequency for luminance samples for SD-SDI 3:4 video, ITU-R (formerly CCIR) BT.601. The chrominance difference samples goes at 6,75 MHz sampling frequency. These samples are 10 bit, so you get a 27 MHz rate of 10 bit samples or 270 Mb/s rate of the full SD-SDI signal (then only called SDI signal). 18 MHz then relates to that in the 16:9 format variant producing according to the same logic a 360 Mb/s rate SDI signal, but it's essentially dead. 18 MHz is also used in analog video synthesis as it relates well to many signals. 27 MHz is a magic frequency as both PAL and NTSC relates in an easy relationship to it. PAL: 25 * 625 * 432 * 4 = 27 MHz NTSC: 30/1.001 * 525 * 429 * 4 = 27 MHz The factor of 4 is for the 4 samples of luminance and chrominance differences. Related frequencies for HD-SDI is: European 25 * 1125 * 1320 * 4 = 148,5 MHz = 11/2 * 27 MHz US 30/1.001 * 1125 * 1100 * 4 = 148,35 MHz = 148,5/1.001 MHz = 11/2.002 * 27 MHz (Let me tell you that I hate the 1.001 factor for HD-SDI rates) Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
Brooke, 25 MHz (and to a lesser extent 50 MHz) is used to clock Ethernet PHYs. It's multiplied up to the various clocks needed internally (125,250,625 MHz etc.) -Eric On Wed, Dec 14, 2011 at 7:13 PM, Brooke Clarke bro...@pacific.net wrote: Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz 40.0 75.0 76.79 76.8 76.81 96.0 3.072 MHz 4.0 4.096 5.0 6.0 7.3729 8.0 8.192 9.8304 10.0 11.0 11.0592 11.2896 12.0 12.288 12.352 13.5 14.31818 15.36 16.0 16.384 17.734475 18.0 18.432 19.6608 19.44 22.1184 24.0 24.567 25.0 25.175 28.63636 30.0 1.4204058 GHz Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Peter Bell wrote: It's exactly 52 times the 1.2288MHz reference that IS95/CDMA2K uses - this may be a coincidence, but I somehow doubt it. Regards, Pete On Thu, Dec 15, 2011 at 3:46 AM, Joe Leikhimjleik...@leikhim.com wrote: I have been watching this thread and may have missed something. My questions: What is the purpose of the outboard OCXO VECTRON 63.8976Mhz? What model number does this RB most closely resemble? -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida www.Leikhim.com jleik...@leikhim.com 407-982-0446 Note to GMail Account users. Due to an abnormally high volume of spam originating from bogus GMail accounts, I have found it necessary to block certain GMail traffic. Please phone me if you believe your message was not received. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- --Eric _ Eric Garner ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
and the one right at the bottom 1.4204058 GHz is the atomic hydrogen rest frequency to those of us with a vague interest in Radio astronomy :-)) Alan G3NYK - Original Message - From: Brooke Clarke bro...@pacific.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Thursday, December 15, 2011 3:13 AM Subject: [time-nuts] Why these Crystal Frequencies? Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz 40.0 75.0 76.79 76.8 76.81 96.0 3.072 MHz 4.0 4.096 5.0 6.0 7.3729 8.0 8.192 9.8304 10.0 11.0 11.0592 11.2896 12.0 12.288 12.352 13.5 14.31818 15.36 16.0 16.384 17.734475 18.0 18.432 19.6608 19.44 22.1184 24.0 24.567 25.0 25.175 28.63636 30.0 1.4204058 GHz Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Peter Bell wrote: It's exactly 52 times the 1.2288MHz reference that IS95/CDMA2K uses - this may be a coincidence, but I somehow doubt it. Regards, Pete On Thu, Dec 15, 2011 at 3:46 AM, Joe Leikhimjleik...@leikhim.com wrote: I have been watching this thread and may have missed something. My questions: What is the purpose of the outboard OCXO VECTRON 63.8976Mhz? What model number does this RB most closely resemble? -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida www.Leikhim.com jleik...@leikhim.com 407-982-0446 Note to GMail Account users. Due to an abnormally high volume of spam originating from bogus GMail accounts, I have found it necessary to block certain GMail traffic. Please phone me if you believe your message was not received. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
Hi Azelio: Sorry, a mistake. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Azelio Boriani wrote: SD-SDI 270MHz, then there is the HD-SDI. Brooke, the 77.503KHz you mention for the DCF77: are you sure the IF is 3KHz? 77.503KHz is 77.5KHz + 3Hz... On Thu, Dec 15, 2011 at 11:54 AM, Heinzmann, Stefan (ALC NetworX GmbH) stefan.heinzm...@alcnetworx.de wrote: 13.5 and 27 MHz are usually associated with digital video. SD video with 720 x 576 has a pixel clock of 13.5 MHz, and the corresponding SDI bit clock is 270 MHz. Cheers Stefan -Ursprüngliche Nachricht- Von: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] Im Auftrag von Brooke Clarke Gesendet: Donnerstag, 15. Dezember 2011 04:13 An: Discussion of precise time and frequency measurement Betreff: [time-nuts] Why these Crystal Frequencies? Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz 40.0 75.0 76.79 76.8 76.81 96.0 3.072 MHz 4.0 4.096 5.0 6.0 7.3729 8.0 8.192 9.8304 10.0 11.0 11.0592 11.2896 12.0 12.288 12.352 13.5 14.31818 15.36 16.0 16.384 17.734475 18.0 18.432 19.6608 19.44 22.1184 24.0 24.567 25.0 25.175 28.63636 30.0 1.4204058 GHz Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Peter Bell wrote: It's exactly 52 times the 1.2288MHz reference that IS95/CDMA2K uses - this may be a coincidence, but I somehow doubt it. Regards, Pete On Thu, Dec 15, 2011 at 3:46 AM, Joe Leikhimjleik...@leikhim.com wrote: I have been watching this thread and may have missed something. My questions: What is the purpose of the outboard OCXO VECTRON 63.8976Mhz? What model number does this RB most closely resemble? -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida www.Leikhim.com jleik...@leikhim.com 407-982-0446 Note to GMail Account users. Due to an abnormally high volume of spam originating from bogus GMail accounts, I have found it necessary to block certain GMail traffic. Please phone me if you believe your message was not received. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Why these Crystal Frequencies?
Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz 40.0 75.0 76.79 76.8 76.81 96.0 3.072 MHz 4.0 4.096 5.0 6.0 7.3729 8.0 8.192 9.8304 10.0 11.0 11.0592 11.2896 12.0 12.288 12.352 13.5 14.31818 15.36 16.0 16.384 17.734475 18.0 18.432 19.6608 19.44 22.1184 24.0 24.567 25.0 25.175 28.63636 30.0 1.4204058 GHz Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Peter Bell wrote: It's exactly 52 times the 1.2288MHz reference that IS95/CDMA2K uses - this may be a coincidence, but I somehow doubt it. Regards, Pete On Thu, Dec 15, 2011 at 3:46 AM, Joe Leikhimjleik...@leikhim.com wrote: I have been watching this thread and may have missed something. My questions: What is the purpose of the outboard OCXO VECTRON 63.8976Mhz? What model number does this RB most closely resemble? -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida www.Leikhim.com jleik...@leikhim.com 407-982-0446 Note to GMail Account users. Due to an abnormally high volume of spam originating from bogus GMail accounts, I have found it necessary to block certain GMail traffic. Please phone me if you believe your message was not received. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
Brooke, 14.31818 is 4x the analog color burst (~3.58) 18.432 divides cleanly for baud rates. I've used it as a PIC clock for that. I think some of the others may be too, but I didn't recognize or do the math to see. On 12/14/2011 7:13 PM, Brooke Clarke wrote: Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz ... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
Hi Rex: Thanks, I had 14.7456 mis listed (off one row) as the 4X CB freq. I've updated the table. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Rex wrote: Brooke, 14.31818 is 4x the analog color burst (~3.58) 18.432 divides cleanly for baud rates. I've used it as a PIC clock for that. I think some of the others may be too, but I didn't recognize or do the math to see. On 12/14/2011 7:13 PM, Brooke Clarke wrote: Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz ... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
11.0592MHz is another crystal used for accurate baud rates - especially on MCUs that had a 12MHz maximum clock (like the Intel 8051) So is 9.8304MHz - used on a number of Mototola (now Freescale) MCUs 17.734475 is 4 times the PAL color burst frequency of 4.433619MHz I'll see if I can think of anything else. Regards, Pete On Thu, Dec 15, 2011 at 11:54 AM, Brooke Clarke bro...@pacific.net wrote: Hi Rex: Thanks, I had 14.7456 mis listed (off one row) as the 4X CB freq. I've updated the table. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Rex wrote: Brooke, 14.31818 is 4x the analog color burst (~3.58) 18.432 divides cleanly for baud rates. I've used it as a PIC clock for that. I think some of the others may be too, but I didn't recognize or do the math to see. On 12/14/2011 7:13 PM, Brooke Clarke wrote: Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz ... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
Ah, and I just noticed that you had the H-Maser and Rb marked wrong On Thu, Dec 15, 2011 at 12:17 PM, Peter Bell bell.pe...@gmail.com wrote: 11.0592MHz is another crystal used for accurate baud rates - especially on MCUs that had a 12MHz maximum clock (like the Intel 8051) So is 9.8304MHz - used on a number of Mototola (now Freescale) MCUs 17.734475 is 4 times the PAL color burst frequency of 4.433619MHz I'll see if I can think of anything else. Regards, Pete On Thu, Dec 15, 2011 at 11:54 AM, Brooke Clarke bro...@pacific.net wrote: Hi Rex: Thanks, I had 14.7456 mis listed (off one row) as the 4X CB freq. I've updated the table. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/Brooke4Congress.html Rex wrote: Brooke, 14.31818 is 4x the analog color burst (~3.58) 18.432 divides cleanly for baud rates. I've used it as a PIC clock for that. I think some of the others may be too, but I didn't recognize or do the math to see. On 12/14/2011 7:13 PM, Brooke Clarke wrote: Hi Pete: Maybe you can shed some light on the common xtal frequencies table where there's no explanation given? http://www.prc68.com/I/pdf/Crystal_Freq.pdf An answer is not it's an even frequency or it's an even binary frequency. That's true for most of these and the factors are part of the table above. The question is why do they exist? such as: 32.0 kHz ... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
A lot of them are derivatives of the 2.4576 UART baud rate gen: 9.8304 = 2.4576 * 4 14.7456 = 2.4576 * 6 19.6608 = 2.4576 * 8 22.1184 = 2.4576 * 9 24.567 = 2.4576 * 10 That is the reason why I've used some of them (14.7456MHz and 19.6608MHz) for clocking the HC11 variants with 4 and 5MHz internal clock (long ago... :) ). Regards, Javier ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Why these Crystal Frequencies?
adding to the sub ordinate: 32.768khz is a common resonator / crystal frequency for Real Time Clocks. Note this is not time-nut RTC My general rule of thumb is that anything that will cleanly divide by 2 (a binary number) can be use for time applications with little or no work in either hardware or software. Steve On Thu, Dec 15, 2011 at 2:37 AM, Javier Herrero jherr...@hvsistemas.eswrote: A lot of them are derivatives of the 2.4576 UART baud rate gen: 9.8304 = 2.4576 * 4 14.7456 = 2.4576 * 6 19.6608 = 2.4576 * 8 22.1184 = 2.4576 * 9 24.567 = 2.4576 * 10 That is the reason why I've used some of them (14.7456MHz and 19.6608MHz) for clocking the HC11 variants with 4 and 5MHz internal clock (long ago... :) ). Regards, Javier ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
