can't add entry to crontab

I am trying to add entries to crontab and I found this post :

I added this file to /boot/config/plugins/dynamix/my_cron.cron

# run backup script on Home\ Video to copy to Backup1 every Sunday at 4am
0 4 * * 0 /boot/config/my_scripts/backup_home_video.sh
# run script to list individual disk contents
0 4 * * 0 /boot/config/my_scripts/list_disks.sh

I ran update_cron and then did crontab -l.  Here is the result:

# If you don't want the output of a cron job mailed to you, you have to direct
# any output to /dev/null.  We'll do this here since these jobs should run
# properly on a newly installed system.  If a script fails, run-parts will
# mail a notice to root.
#
# Run the hourly, daily, weekly, and monthly cron jobs.
# Jobs that need different timing may be entered into the crontab as before,
# but most really don't need greater granularity than this.  If the exact
# times of the hourly, daily, weekly, and monthly cron jobs do not suit your
# needs, feel free to adjust them.
#
# Run hourly cron jobs at 47 minutes after the hour:
47 * * * * /usr/bin/run-parts /etc/cron.hourly 1> /dev/null
#
# Run daily cron jobs at 4:40 every day:
40 4 * * * /usr/bin/run-parts /etc/cron.daily 1> /dev/null
#
# Run weekly cron jobs at 4:30 on the first day of the week:
30 4 * * 0 /usr/bin/run-parts /etc/cron.weekly 1> /dev/null
#
# Run monthly cron jobs at 4:20 on the first day of the month:
20 4 1 * * /usr/bin/run-parts /etc/cron.monthly 1> /dev/null
0 3 * * * /usr/local/emhttp/plugins/ca.backup2/scripts/backup.php &>/dev/null 2>&1

It did not add my entries to crontab.  I rebooted and crontab is still the same.

So: how does one add an entry to crontab and have it re-inserted on bootup?

Edited November 5, 20187 yr by CaptainTivo
added name of file