# Europe DCF77 synchronized servers question **URL:** \ **Category:** Server operators\ **Tags:** monitoring\ **Created:** [September 18, 2021, 12:01pm UTC](https://community.ntppool.org/t/europe-dcf77-synchronized-servers-question/2155 "2021-09-18T12:01:29Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![iwik](https://avatars.discourse-cdn.com/v4/letter/i/59ef9b/32.png) [@iwik](https://community.ntppool.org/u/iwik)\ **Post date:** [September 18, 2021, 12:01pm UTC](https://community.ntppool.org/t/europe-dcf77-synchronized-servers-question/2155/1 "2021-09-18T12:01:29Z")
Hi team, I am running ntpd with DCF77 receiver. Ntpd sometimes crash, when signal is bad, but not often. Today I noticed multiple crashes of ntpd and also I have seen my one of my DCF77 clock had bad time. It was some time forward (half hour-hour?). Later alert from [pool.ntp.org](http://pool.ntp.org) monitoring had come, that server is not reachable - but ntpd was running (it have auto-restart). Graph is really strange ![image](https://us1.discourse-cdn.com/flex016/uploads/ntppool/original/1X/292da49a148ba3304fc29368fc133ebe969da1b7.png) I can’t see any ~1800 values which are in graph in data [https://www.ntppool.org/scores/62.197.224.14/log?limit=200&monitor=\*](https://www.ntppool.org/scores/62.197.224.14/log?limit=200&monitor=*) DCF77 logs [dcf77logs.de - Dcf-Daten aus DcfLog\_20210918.dcf](https://dcf77logs.de/logs/DcfLog_20210918/dcf) does not show any problems. Anybody else running ntpd with dcf77? Share your experience. ---
**Author:** ![Bas](https://sea2.discourse-cdn.com/flex016/user_avatar/community.ntppool.org/bas/32/465_2.png) [@Bas](https://community.ntppool.org/u/Bas)\ **Post date:** [September 18, 2021, 3:53pm UTC](https://community.ntppool.org/t/europe-dcf77-synchronized-servers-question/2155/2 "2021-09-18T15:53:23Z")
You could install Chrony instead, it’s a lot more stable then NTPD. Your NTP-deamon should not crash, if it does it could be a problem with your hardware. Or because of your DCF77 receiver, it could be due to overloading of the DCF77 receiver if you have big AM-stations near you. You could install a band-pass filter to block unwanted signals near you. AM-stations make a lot of power, and they can easily make your receiver go nuts or take the entire computer down. When I’m transmitting on 160m (Radio Amateur band) my DCF77 weather-station stops receiving because of receiver overload. Could be your problem, overloading because of some station near you. ---
**Author:** ![iwik](https://avatars.discourse-cdn.com/v4/letter/i/59ef9b/32.png) [@iwik](https://community.ntppool.org/u/iwik)\ **Post date:** [September 18, 2021, 4:44pm UTC](https://community.ntppool.org/t/europe-dcf77-synchronized-servers-question/2155/3 "2021-09-18T16:44:11Z")
It seems to crash on decoding, usually during some storms nearby. > 18 Sep 14:47:38 ntpd[31111]: parse: convert\_rawdcf: INCOMPLETE DATA - time code only has 38 bits > 18 Sep 14:48:00 ntpd[31111]: parse: convert\_rawdcf: INCOMPLETE DATA - time code only has 21 bits > 18 Sep 14:48:56 ntpd[31111]: parse: convert\_rawdcf: INCOMPLETE DATA - time code only has 56 bits > 18 Sep 14:49:00 ntpd[31111]: parse: convert\_rawdcf: INCOMPLETE DATA - time code only has 3 bits > 18 Sep 14:50:00 ntpd[31111]: PARSE receiver #0: FAILED TIMECODE: “-##############RAD-LS-24-124P-24812P12481212412-8112481248P” (check receiver configuration / wiring) > 18 Sep 15:22:00 ntpd[31111]: parse: convert\_rawdcf: start bit / parity check FAILED for “-----##----#-##–D–S-24–24p1-4812P–481–241–8-1----2–p” > 18 Sep 15:22:00 ntpd[31111]: PARSE receiver #0: interval for following error message class is at least 00:01:00 > 18 Sep 15:22:00 ntpd[31111]: PARSE receiver #0: FAILED TIMECODE: “-----##----#-##–D–S-24–24p1-4812P–481–241–8-1----2–” (check receiver configuration / wiring) Chrony was not an option - it did not have support for DCF receivers. Now as I am checking, it maybe changed - I have found [GitHub - mlichvar/ntp-refclock: Wrapper for ntpd reference clock drivers](https://github.com/mlichvar/ntp-refclock). I give it a try. Receiver is “black box” (from ebay), I don’t want to make any hardware hacks. Anyway thanks for reply, it make I have discover ntp-refclock ---
**Author:** ![stevesommars](https://sea2.discourse-cdn.com/flex016/user_avatar/community.ntppool.org/stevesommars/32/2075_2.png) [@stevesommars](https://community.ntppool.org/u/stevesommars)\ **Post date:** [September 18, 2021, 10:08pm UTC](https://community.ntppool.org/t/europe-dcf77-synchronized-servers-question/2155/4 "2021-09-18T22:08:15Z")
The DCF77 signal is shown in [WIkipedia](https://en.wikipedia.org/wiki/DCF77). The signal isn’t robust. A few fields are protected by parity, but that’s all. The NTP Pool monitors saw NTP Server reports Alarm (LI=3) 2021-09-18 10:18:34 Alarm 2021-09-18 10:45:47 " 2021-09-18 11:13:59 " 2021-09-18 19:45:04 Port unreachable 2021-09-18 20:02:02 Alarm My monitoring client showed a high error about 11:00 ![image](https://us1.discourse-cdn.com/flex016/uploads/ntppool/original/1X/689c1d4bb3542de338c2ca1f67f0881ee837b9f3.png) DCF77 needs good RF