Re: [beagleboard] 625 MHz leak?
Gunter, We tried that and this did not work for us. The noise was still there. They said the noise was coming out with a clock signal. Any ideas? Should we check the crystals or something else? Any ideas? Regards, Shu On Saturday, January 31, 2015 at 12:23:15 PM UTC-6, dl4mea wrote: In a similar problem it helped for me to replace the 0.1R that connectes Ethernet shield to the frame of the Beaglebone by a simple solder bridge. This resistor is located on the solder side of the Beaglebone, just below the network connector. I have a spectrum analyzer and a 3GHz active probe and was astonished about the amount of infuence. Sounds crazy but prooven many times meanwhile. Regards, Günter -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] 625 MHz leak?
In a similar problem it helped for me to replace the 0.1R that connectes Ethernet shield to the frame of the Beaglebone by a simple solder bridge. This resistor is located on the solder side of the Beaglebone, just below the network connector. I have a spectrum analyzer and a 3GHz active probe and was astonished about the amount of infuence. Sounds crazy but prooven many times meanwhile. Regards, Günter -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] 625 MHz leak?
Liyaoshi, We have the same problem. I agree with what you mentioned. We checked If the RJ45 cable is not plugged in, but still failed the Radiated emissions test. What else we should look into? the RJ45 connector has the integrated magnetic. Regards, Shu On Wednesday, May 14, 2014 at 9:52:10 PM UTC-5, liyaoshi wrote: 625M clock noise maybe from 125M clocksource， or 25M This might be from ethernet Do you use GIGA ethernet ? And Try to unplug the RJ45 cable 2014-05-15 5:01 GMT+08:00 Gerald Coley ger...@beagleboard.org javascript:: OK. Understood. Different test equipment will yield different results. And it can be effected by the SW you are running. Gerald On Wed, May 14, 2014 at 3:59 PM, l...@ansync.com javascript: wrote: It's not something unique to our board--a stock BBB has the same problem. On Wednesday, May 14, 2014 1:41:29 PM UTC-7, Gerald wrote: Sounds like you may have grounding issues or unterminated pin . Using a probe should let you be able to determine which side of the chip it is. Gerald On Wed, May 14, 2014 at 3:37 PM, l...@ansync.com wrote: It seems to come from right around the processor, but we couldn't pinpoint it any more precisely than that, or even to one side of the board or other. On Wednesday, May 14, 2014 10:56:28 AM UTC-7, Gerald wrote: In order to mitigate it you need to figure out where it is coming from. A probe test will help in that area. Have you run one? Using ferrites on all cables generally helps in these types of issues. Gerald On Wed, May 14, 2014 at 12:01 PM, l...@ansync.com wrote: We have a BBB-based design currently undergoing FCC testing, and they've found a bit of noise at 625 MHz. Has anyone else encountered this, or know what it might be, or how to mitigate it? -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com javascript:. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com javascript:. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] 625 MHz leak?
Lee, Did you find out what cause the noise? We have the same problem right now. Our noise is from 300M to 600M. Regards, Shu On Wednesday, May 14, 2014 at 3:59:24 PM UTC-5, Lee Crocker wrote: It's not something unique to our board--a stock BBB has the same problem. On Wednesday, May 14, 2014 1:41:29 PM UTC-7, Gerald wrote: Sounds like you may have grounding issues or unterminated pin . Using a probe should let you be able to determine which side of the chip it is. Gerald On Wed, May 14, 2014 at 3:37 PM, l...@ansync.com wrote: It seems to come from right around the processor, but we couldn't pinpoint it any more precisely than that, or even to one side of the board or other. On Wednesday, May 14, 2014 10:56:28 AM UTC-7, Gerald wrote: In order to mitigate it you need to figure out where it is coming from. A probe test will help in that area. Have you run one? Using ferrites on all cables generally helps in these types of issues. Gerald On Wed, May 14, 2014 at 12:01 PM, l...@ansync.com wrote: We have a BBB-based design currently undergoing FCC testing, and they've found a bit of noise at 625 MHz. Has anyone else encountered this, or know what it might be, or how to mitigate it? -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] 625 MHz leak?
In order to mitigate it you need to figure out where it is coming from. A probe test will help in that area. Have you run one? Using ferrites on all cables generally helps in these types of issues. Gerald On Wed, May 14, 2014 at 12:01 PM, l...@ansync.com wrote: We have a BBB-based design currently undergoing FCC testing, and they've found a bit of noise at 625 MHz. Has anyone else encountered this, or know what it might be, or how to mitigate it? -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] 625 MHz leak?
It seems to come from right around the processor, but we couldn't pinpoint it any more precisely than that, or even to one side of the board or other. On Wednesday, May 14, 2014 10:56:28 AM UTC-7, Gerald wrote: In order to mitigate it you need to figure out where it is coming from. A probe test will help in that area. Have you run one? Using ferrites on all cables generally helps in these types of issues. Gerald On Wed, May 14, 2014 at 12:01 PM, l...@ansync.com javascript: wrote: We have a BBB-based design currently undergoing FCC testing, and they've found a bit of noise at 625 MHz. Has anyone else encountered this, or know what it might be, or how to mitigate it? -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com javascript:. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] 625 MHz leak?
Sounds like you may have grounding issues or unterminated pin . Using a probe should let you be able to determine which side of the chip it is. Gerald On Wed, May 14, 2014 at 3:37 PM, l...@ansync.com wrote: It seems to come from right around the processor, but we couldn't pinpoint it any more precisely than that, or even to one side of the board or other. On Wednesday, May 14, 2014 10:56:28 AM UTC-7, Gerald wrote: In order to mitigate it you need to figure out where it is coming from. A probe test will help in that area. Have you run one? Using ferrites on all cables generally helps in these types of issues. Gerald On Wed, May 14, 2014 at 12:01 PM, l...@ansync.com wrote: We have a BBB-based design currently undergoing FCC testing, and they've found a bit of noise at 625 MHz. Has anyone else encountered this, or know what it might be, or how to mitigate it? -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] 625 MHz leak?
It's not something unique to our board--a stock BBB has the same problem. On Wednesday, May 14, 2014 1:41:29 PM UTC-7, Gerald wrote: Sounds like you may have grounding issues or unterminated pin . Using a probe should let you be able to determine which side of the chip it is. Gerald On Wed, May 14, 2014 at 3:37 PM, l...@ansync.com javascript: wrote: It seems to come from right around the processor, but we couldn't pinpoint it any more precisely than that, or even to one side of the board or other. On Wednesday, May 14, 2014 10:56:28 AM UTC-7, Gerald wrote: In order to mitigate it you need to figure out where it is coming from. A probe test will help in that area. Have you run one? Using ferrites on all cables generally helps in these types of issues. Gerald On Wed, May 14, 2014 at 12:01 PM, l...@ansync.com wrote: We have a BBB-based design currently undergoing FCC testing, and they've found a bit of noise at 625 MHz. Has anyone else encountered this, or know what it might be, or how to mitigate it? -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com javascript:. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] 625 MHz leak?
OK. Understood. Different test equipment will yield different results. And it can be effected by the SW you are running. Gerald On Wed, May 14, 2014 at 3:59 PM, l...@ansync.com wrote: It's not something unique to our board--a stock BBB has the same problem. On Wednesday, May 14, 2014 1:41:29 PM UTC-7, Gerald wrote: Sounds like you may have grounding issues or unterminated pin . Using a probe should let you be able to determine which side of the chip it is. Gerald On Wed, May 14, 2014 at 3:37 PM, l...@ansync.com wrote: It seems to come from right around the processor, but we couldn't pinpoint it any more precisely than that, or even to one side of the board or other. On Wednesday, May 14, 2014 10:56:28 AM UTC-7, Gerald wrote: In order to mitigate it you need to figure out where it is coming from. A probe test will help in that area. Have you run one? Using ferrites on all cables generally helps in these types of issues. Gerald On Wed, May 14, 2014 at 12:01 PM, l...@ansync.com wrote: We have a BBB-based design currently undergoing FCC testing, and they've found a bit of noise at 625 MHz. Has anyone else encountered this, or know what it might be, or how to mitigate it? -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] 625 MHz leak?
625M clock noise maybe from 125M clocksource， or 25M This might be from ethernet Do you use GIGA ethernet ? And Try to unplug the RJ45 cable 2014-05-15 5:01 GMT+08:00 Gerald Coley ger...@beagleboard.org: OK. Understood. Different test equipment will yield different results. And it can be effected by the SW you are running. Gerald On Wed, May 14, 2014 at 3:59 PM, l...@ansync.com wrote: It's not something unique to our board--a stock BBB has the same problem. On Wednesday, May 14, 2014 1:41:29 PM UTC-7, Gerald wrote: Sounds like you may have grounding issues or unterminated pin . Using a probe should let you be able to determine which side of the chip it is. Gerald On Wed, May 14, 2014 at 3:37 PM, l...@ansync.com wrote: It seems to come from right around the processor, but we couldn't pinpoint it any more precisely than that, or even to one side of the board or other. On Wednesday, May 14, 2014 10:56:28 AM UTC-7, Gerald wrote: In order to mitigate it you need to figure out where it is coming from. A probe test will help in that area. Have you run one? Using ferrites on all cables generally helps in these types of issues. Gerald On Wed, May 14, 2014 at 12:01 PM, l...@ansync.com wrote: We have a BBB-based design currently undergoing FCC testing, and they've found a bit of noise at 625 MHz. Has anyone else encountered this, or know what it might be, or how to mitigate it? -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups BeagleBoard group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
