PIcked up a couple of large size Radio Shack 63-960 LED clocks with Settable alarm, at local Goodwill store. $3.00 ea work great see across room, loud Alarm, etc... Barely missed, by seconds, getting a classic Hallicrafters General coverage receiver (not like say, S-38) but a larger light green metal box. nearly perfect condx. $25.00 with the famous h logo speaker probably late 50s Vintage. :-( Dang... Checked LED clocks by ear and eye with WWV, They drift a few seconds in the course of a few days, and wander back and forth. Thought AC mains frequency was tighter than that. They use an LM 8560 Clock chip. Uses a switchable AC mains frequency reference pin 50/60 hz. Want to provide an accurate (relatively accurate) 60 hz reference to the chip. Some room inside for custom modifications. Does a TCXO or similar exist in a small package that provides 60 hz ticks? Best, 73, Pat Barthelow AA6EG apol <apolloeme@gmail.com>loeme@gmail.com *"The most exciting phrase to hear in Science, the one that heraldsnew discoveries, is not "Eureka, I have found it!" but:* "That's funny..." ----Isaac Asimov

http://leapsecond.com/pages/mains/

http://leapsecond.com/pic/src/pd60.asm
http://leapsecond.com/pic/src/pd60.hex

Pat, > They drift a few seconds in the course of a few days, and wander back and forth. Yes, it's normal for AC mains to drift around by a few seconds over a day but it usually stays roughly on-time over weeks and months. Here's an old example of monitoring mains time & frequency for 45 days: http://leapsecond.com/pages/mains/ > Does a TCXO or similar exist in a small package that provides 60 hz ticks? If you have 10 MHz (XO, TCXO, etc.) you can convert to 60 Hz using a $1 PIC divider: http://leapsecond.com/pic/src/pd60.asm http://leapsecond.com/pic/src/pd60.hex /tvb ----- Original Message ----- From: "Patrick Barthelow" <apolloeme@gmail.com> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Thursday, December 14, 2017 8:42 AM Subject: [time-nuts] accurate 60 hz reference chips/ckts > PIcked up a couple of large size Radio Shack 63-960 LED clocks with > Settable alarm, at local Goodwill store. $3.00 ea work great see across > room, loud Alarm, etc... > > > Barely missed, by seconds, getting a classic Hallicrafters General coverage > receiver > (not like say, S-38) but a larger light green metal box. nearly perfect > condx. $25.00 with the famous h logo speaker probably late 50s Vintage. > :-( Dang... > Checked LED clocks by ear and eye with WWV, They drift a few seconds in > the course of a few days, and wander back and forth. Thought AC mains > frequency was tighter than that. They use an LM 8560 Clock chip. Uses a > switchable AC mains frequency reference pin 50/60 hz. > Want to provide an accurate (relatively accurate) 60 hz reference to the > chip. Some room inside for custom modifications. Does a TCXO or similar > exist in a small package that provides 60 hz ticks? > > Best, 73, Pat Barthelow AA6EG > apol <apolloeme@gmail.com>loeme@gmail.com > > > *"The most exciting phrase to hear in Science, the one that heraldsnew > discoveries, is not "Eureka, I have found it!" but:* > "That's funny..." ----Isaac Asimov