[time-nuts] FTS 1200 transistor replacement
Traced the problem of my FTS 1200 to the first BC109 Transistor on the A2/A3 AGS/Amplifier board. Since it is right after the Oscillator transistor low noise is critical. This unit is at least 30 years old and my question is, what transistor will have even lower noise than the than low noise BC 109. Voltage is 6.43 V. Thanks Bert Kehren ___ 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] iTrax130
Hello, Just got this board from a Chinese ebayer, but unable to find any document about the pin-assignment. Anybody can help... Many thanks and brgds, Ernie. ___ 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] time-nuts Digest, Vol 118, Issue 35 Message: 3
Hi, Traced the problem of my FTS 1200 to the first BC109 Transistor on the A2/A3 AGS/Amplifier board. Since it is right after the Oscillator transistor low noise is critical. This unit is at least 30 years old and my question is, what transistor will have even lower noise than the than low noise BC 109. Voltage is 6.43 V. A BC 549 is a replacement Walter -Ursprüngliche Nachricht- Von: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] Im Auftrag von time-nuts-requ...@febo.com Gesendet: Samstag, 17. Mai 2014 18:00 An: time-nuts@febo.com Betreff: time-nuts Digest, Vol 118, Issue 35 Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than Re: Contents of time-nuts digest... Today's Topics: 1. Re: Fwd: CGSIC: Known Problem With Certain GPS Devices (Magnus Danielson) 2. Re: Fwd: CGSIC: Known Problem With Certain GPS Devices (Brooke Clarke) 3. FTS 1200 transistor replacement (ewkeh...@aol.com) -- Message: 1 Date: Sat, 17 May 2014 01:01:50 +0200 From: Magnus Danielson mag...@rubidium.dyndns.org To: time-nuts@febo.com Subject: Re: [time-nuts] Fwd: CGSIC: Known Problem With Certain GPS Devices Message-ID: 537698de.2050...@rubidium.dyndns.org Content-Type: text/plain; charset=ISO-8859-1; format=flowed They can't point official fingers. That's why. Ask you vendor if they need firmware upgrades to comply in this aspect. Cheers, Magnus On 05/16/2014 12:39 AM, saidj...@aol.com wrote: It would be good to understand which receivers are adversely affected by this.. the USCG did not list affected vendors/devices.. In a message dated 5/15/2014 15:19:51 Pacific Daylight Time, mag...@rubidium.dyndns.org writes: Hi fellow time-nuts, I think this message is interesting. It shows that some receiver vendors have been cheating on an important detail, ignoring the health status and being confused as a result. Cheers, Magnus Original Message Subject: CGSIC: Known Problem With Certain GPS Devices Date: Thu, 15 May 2014 21:20:23 + From: Civil Global Positioning System Service Interface Committee (CGSIC) cg...@cgls.uscg.mil Reply-To: cg...@cgls.uscg.mil To: cg...@cgls.uscg.mil cg...@cgls.uscg.mil All CGSIC: May 15, 2014 Recently, many GPS users have reported intermittent GPS outages in their devices. After investigating, the U.S. government has linked the problem to flawed processing of GPS satellite data within certain GPS receiver chipsets. The GPS satellite service continues to function as designed and is fully operational and available worldwide. The problem affects only user equipment that erroneously ignores the satellite health status information broadcast from every GPS satellite. The problem is not related to the April 28, 2014, activation of civil navigation messages on the GPS L2C and L5 signals. Since March 15, 2014, the Air Force has been conducting functional checkout on a GPS satellite, designated Space Vehicle Number (SVN) 64. SVN 64 broadcasts a data message that clearly indicates SVN 64 is unusable for navigation. Nevertheless, the U.S. government has confirmed that certain GPS receivers are using data from SVN 64, in violation of GPS interface specifications, resulting in outages or corrupted, inaccurate position calculations. The Air Force testing is scheduled to end in mid-May 2014 at which time SVN 64 will begin normal operation. At that point, these problems may stop occurring. Meanwhile, the U.S. government urges all GPS device makers to review their products for compliance with the GPS interface specifications, and if necessary, to issue software/firmware updates to users as soon as possible. View specifications http://www.gps.gov/technical/icwg/ Users experiencing GPS outages should check with their device manufacturers for available software/firmware updates. In addition, any civil user seeing unusual behavior in GPS user equipment should report it to the U.S. Coast Guard Navigation Center (NAVCEN). Aviation users should file reports consistent with FAA-approved procedures. Military users seeing unusual behavior should report it the GPS Operations Center (GPSOC). Please direct any civil user questions to NAVCEN at (703) 313-5900, http://www.navcen.uscg.gov Please direct any military user questions to the GPSOC at (719) 567-2541, DSN: 560-2541, gpsoperationscen...@us.af.mil https://gps.afspc.af.mil Military alternate: Joint
Re: [time-nuts] FTS 1200 transistor replacement
Hi The 2N5089 from ON semi is a pretty good bet for a high beta / audio part. They are $0.37 a piece from Mouser with 11,542 in stock. Bob On May 17, 2014, at 11:37 AM, ewkeh...@aol.com wrote: Traced the problem of my FTS 1200 to the first BC109 Transistor on the A2/A3 AGS/Amplifier board. Since it is right after the Oscillator transistor low noise is critical. This unit is at least 30 years old and my question is, what transistor will have even lower noise than the than low noise BC 109. Voltage is 6.43 V. Thanks Bert Kehren ___ 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] FTS 1200 transistor replacement
Bert wrote: what transistor will have even lower noise than the than low noise BC 109. Generally speaking, the baseband noise of a bipolar transistor is most strongly influenced by the transistor's base spreading resistance. Of course, the transistor also needs to have whatever other characteristics are required in the application circuit -- in particular, adequate current gain and transition frequency at the operating point and sufficiently low input capacitance -- and these may be mutually exclusive with lowest base spreading resistance. The 2SD786 and MPSA18 may be good candidates. That said, I seriously doubt you will get usefully better phase noise by using a better transistor in this location. Best regards, Charles ___ 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] FTS 1200 transistor replacement
Thanks for all the help. I do have a couple of BC 109 but I thought with all the work to carefully disassemble the unit that after 30 years there would be a better transistor. Thanks again Bert Kehren In a message dated 5/17/2014 6:47:55 P.M. Eastern Daylight Time, csteinm...@yandex.com writes: Bert wrote: what transistor will have even lower noise than the than low noise BC 109. Generally speaking, the baseband noise of a bipolar transistor is most strongly influenced by the transistor's base spreading resistance. Of course, the transistor also needs to have whatever other characteristics are required in the application circuit -- in particular, adequate current gain and transition frequency at the operating point and sufficiently low input capacitance -- and these may be mutually exclusive with lowest base spreading resistance. The 2SD786 and MPSA18 may be good candidates. That said, I seriously doubt you will get usefully better phase noise by using a better transistor in this location. Best regards, Charles ___ 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] FTS 1200 transistor replacement
Thanks for all the help. I do have a couple of BC 109 but I thought with all the work to carefully disassemble the unit that after 30 years there would be a better transistor. The fundamentals of solid state physics haven't changed much in 30 years;-) It's a tribute to semiconductor scientists that our fabrication processes have been delivering devices with very close to theoretical performance for ~50 years. (But I'm still waiting for commercial graphene FETs.) Best regards, Charles ___ 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] OT - Need a German speaker
Are there any German speakers who live in the USA on this list? I need someone to order me a small kit from a German web site. I'll pay you up front to order this for me. http://www.box73.de/product_info.php?products_id=945 It is a speech compressor kit that plugs into the mic of an FT-817. If you can help, please email me offline. Joe Gray W5JG ___ 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] time-nuts Digest, Vol 118, Issue 35 Message: 3
Ulrich Rohde has a low noise oscillator circuit perhaps it is patented, here is:http://f6csx.free.fr/techni/PLL/Oscillators.pdf 73 Alex On 5/17/2014 9:53 AM, Walter Hofstädtler wrote: Hi, Traced the problem of my FTS 1200 to the first BC109 Transistor on the A2/A3 AGS/Amplifier board. Since it is right after the Oscillator transistor low noise is critical. This unit is at least 30 years old and my question is, what transistor will have even lower noise than the than low noise BC 109. Voltage is 6.43 V. A BC 549 is a replacement Walter -Ursprüngliche Nachricht- Von: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] Im Auftrag von time-nuts-requ...@febo.com Gesendet: Samstag, 17. Mai 2014 18:00 An: time-nuts@febo.com Betreff: time-nuts Digest, Vol 118, Issue 35 Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than Re: Contents of time-nuts digest... Today's Topics: 1. Re: Fwd: CGSIC: Known Problem With Certain GPS Devices (Magnus Danielson) 2. Re: Fwd: CGSIC: Known Problem With Certain GPS Devices (Brooke Clarke) 3. FTS 1200 transistor replacement (ewkeh...@aol.com) -- Message: 1 Date: Sat, 17 May 2014 01:01:50 +0200 From: Magnus Danielson mag...@rubidium.dyndns.org To: time-nuts@febo.com Subject: Re: [time-nuts] Fwd: CGSIC: Known Problem With Certain GPS Devices Message-ID: 537698de.2050...@rubidium.dyndns.org Content-Type: text/plain; charset=ISO-8859-1; format=flowed They can't point official fingers. That's why. Ask you vendor if they need firmware upgrades to comply in this aspect. Cheers, Magnus On 05/16/2014 12:39 AM, saidj...@aol.com wrote: It would be good to understand which receivers are adversely affected by this.. the USCG did not list affected vendors/devices.. In a message dated 5/15/2014 15:19:51 Pacific Daylight Time, mag...@rubidium.dyndns.org writes: Hi fellow time-nuts, I think this message is interesting. It shows that some receiver vendors have been cheating on an important detail, ignoring the health status and being confused as a result. Cheers, Magnus Original Message Subject: CGSIC: Known Problem With Certain GPS Devices Date: Thu, 15 May 2014 21:20:23 + From: Civil Global Positioning System Service Interface Committee (CGSIC) cg...@cgls.uscg.mil Reply-To: cg...@cgls.uscg.mil To: cg...@cgls.uscg.mil cg...@cgls.uscg.mil All CGSIC: May 15, 2014 Recently, many GPS users have reported intermittent GPS outages in their devices. After investigating, the U.S. government has linked the problem to flawed processing of GPS satellite data within certain GPS receiver chipsets. The GPS satellite service continues to function as designed and is fully operational and available worldwide. The problem affects only user equipment that erroneously ignores the satellite health status information broadcast from every GPS satellite. The problem is not related to the April 28, 2014, activation of civil navigation messages on the GPS L2C and L5 signals. Since March 15, 2014, the Air Force has been conducting functional checkout on a GPS satellite, designated Space Vehicle Number (SVN) 64. SVN 64 broadcasts a data message that clearly indicates SVN 64 is unusable for navigation. Nevertheless, the U.S. government has confirmed that certain GPS receivers are using data from SVN 64, in violation of GPS interface specifications, resulting in outages or corrupted, inaccurate position calculations. The Air Force testing is scheduled to end in mid-May 2014 at which time SVN 64 will begin normal operation. At that point, these problems may stop occurring. Meanwhile, the U.S. government urges all GPS device makers to review their products for compliance with the GPS interface specifications, and if necessary, to issue software/firmware updates to users as soon as possible. View specifications http://www.gps.gov/technical/icwg/ Users experiencing GPS outages should check with their device manufacturers for available software/firmware updates. In addition, any civil user seeing unusual behavior in GPS user equipment should report it to the U.S. Coast Guard Navigation Center (NAVCEN). Aviation users should file reports consistent with FAA-approved procedures. Military users seeing unusual behavior should report it the GPS Operations Center (GPSOC). Please direct any civil user questions to NAVCEN at (703) 313-5900, http://www.navcen.uscg.gov Please direct any military user questions to the GPSOC at (719)
