Probably because your time is off. If the button below and to the right of your call sign says OFF then tap it so it says UTC and try again.

The error occurs because sat elements are only good for a few days so if the clock's time has been adjusted outside the valid range you'll get an error message. Time can be adjusted away from UTC if you click any of the time fields. That can be handy to intentionally move time forward or backwards to explore gray line, VOACAP predictions etc. See page 7 of the User Guide for more details.

It's probably not wrong but I can think of two possibilities why you might think so:

1. You are near a grid boundary and the HamClock display is misleading because of rounding.

   For example, suppose you set your location to 35.1N 110.1W which is in grid DM45. HamClock will display this in the main DE pane as 35N 110W grid DM45. But taken at face value 35N 110W is in grid DM55 so the grid appears to be wrong because the location is rounded for display. When in doubt, open the lat/long dialog to review the values as they are stored internally.

   Note that displaying more precision would not eliminate this issue entirely, it can only reduce the region where this occurs.

2. There are two different algorithms for exactly where a grid square is located.

   Some programs use the center of a grid for their position, others use the SW corner. HamClock uses the corner because that is the historical technique described in this paper published in January 1989 QST. My personal favorite web site that uses this technique is here. But other popular web sites use the center, such as this one on QRZ.com.

3. So it depends which you consider correct.

Screen blanking control is a complex dance between the host and HamClock, and the music keeps changing.

Let's check the host first.

1. On systems running RPi Debian Bullseye start a terminal
   1. run sudo raspi-config then
      1. Go to Display Options ⇒ Screen Blanking ⇒ Enable
      2. Go to Advanced Options ⇒ Wayland ⇒ Disable
      3. select Finish (don't reboot yet)
   2. HamClock and xscreensaver do not mix. To make sure you don't have it installed, run these commands:
      1. sudo apt remove xscreensaver
      2. sudo apt autoremove
   3. Edit /etc/X11/xorg.conf.d/10-blanking.conf and make sure the line for DPMS shows Enable.
   4. reboot
   5. Log in, open a terminal and type xset dpms force off. If the screen goes blank then HamClock should be able to blank the screen as well. Click your mouse or type any key to get the display back on.
2. On systems running Bookworm, or any system running Wayland, the means to control screen blanking is not yet stable which means the Idle timer and On/Off controls may not work at all. At the very least, on RPi make sure to use the HDMI plug nearest the power port. Give it a try without changing anything first; you might be lucky.

   You may find HamClock can turn the monitor off but it comes right back on again. If this happens edit /boot/firmware/cmdline.txt and add vc4.force_hotplug=1 to the end of the existing line (don't create a new line), then reboot.

   If still no luck, your best bet is to turn off Wayland as follows:

   1. run sudo raspi-config then
      1. Go to Display Options ⇒ Screen Blanking ⇒ Disable
      2. Go to Advanced Options ⇒ Wayland ⇒ Disable
      3. select Finish (don't reboot yet)
   2. Edit /etc/X11/xorg.conf.d/10-blanking.conf and make sure the line for DPMS shows Enable.
   3. Click the Raspberry in the upper left corner to log out and log back in
   4. Open a terminal and type xset dpms force off. If the screen goes blank then HamClock should be able to blank the screen as well. Click your mouse or type any key to get the display back on.
3. It could also be the monitor itself. Activate the monitor's own control menus and look for an option related to automatically setting the input. Turning this off and setting HDMI directly can sometimes help.

As for HamClock itself, it will only blank the screen if:

• Full Screen mode is Yes in Setup page 5
• it was not built to be web-only
• it is displaying on the same system on which it is running

If these criteria are not met then HamClock will not try to blank the screen, thus any blanking that does occur must be caused by the host system, not HamClock.

Follows are the HamClock settings that control when it will blank the screen:

• Check the Idle time in the upper right corner. You may have to click the title region to change options to find the value. Click just above or below the Idle number to increase or decrease by 5 minutes. Set to 0 to display idle blanking.
• Check the Off and On (or Dim) times in the same menu. Change them the same way; set the times equal to disable blanking. These can also be set on a daily basis in Setup page 7.

It is because HamClock is only a single thread of execution so it can only do one thing at a time. Thus, if the network connection is slow everything hangs during file downloads and it can't update the time digits. HamClock tries to reduce this effect by reading in fairly small chunks and updating the time after each chunk completes, but it can still look jerky.

Note the stalling does not affect the accuracy of the internal time keeping because that uses a hardware interrupt, so time proceeds apace regardless of the display.

1. Connect a temporary USB mouse to the micro to usb adapter and plug it into the spare micro usb port.

Now you should be able to use a mouse to naviagte.

2. Exit hamclock (It automatically loads at every boot)

First you need to click on the Padlock Icon  in the top left panel of the Hamclock interface

The icon is directly under the UTC indicator

Choose the option Exit Hamclock option in the menu that appears and then choose ok

You can then use the Network Manager icon in the upper right corner of the Raspberry Pi's desktop:

1. Click on the Wi-Fi icon.
2. Select the network you wish to connect to.
3. Enter the password if prompted using the on-screen keyboard

If the on-screen keyboard does not appear you can launch it from the keyboard icon that is on the task bar of the Raspberry Pi's at the top right hand corner.

Once you have connected via wifi you can remove the usb mouse and either reboot the Raspberry Pi by powering off and back on again or alternatively you can launch Hamclock from the icon on the desktop.

NOTE: USB mouse is only required for configuring the pi and hamclock and can be removed for normal operation.

It will run but you won't see much.

HamClock connects to clearskyinstitute.com for all the data plots, real-time images and maps and to various NTP servers for time. That just leaves the moon, NCDXF beacons, and BME environment data that is sourced locally.

You could get time without a net connection by using a GPS antenna and running gpsd.

On the other hand if you have a slow network connection, see FAQ "Why does the time stall occasionally?"

The accuracy of the reports depends on several factors.

• The data plan that Hamclock uses is Open Weather Map and that provides updates at least every two hours and uses a grid spacing of about ten miles.
• Some of their data comes from models, not actual measurements. This allows them to appear to offer seamless global coverage even in areas that clearly could not have any measuring capabilities, but at the risk of modeling errors.
• HamClock queries for weather using the latitude and longitude given for DE. So the more accurate you specify your location, the better will be the results.

1. In Setup page 2, tap the Cluster? button then set the internet host name and port number for your desired node. A good list is here. HamClock supports DX Spider, AR and CC node types. Not all are active so if the connection fails, try another. If no port is listed, try the usual default of 7300 for Spider and 7373 for AR-Cluster.

   Also on Setup page 2:

   1. You may enter a login different from your call, such as WB0OEW-1. It is important to use unique logins for each program you use at the same time as HamClock which are connecting to the same node. If left blank, HamClock will use your call sign.
   2. You can set one or more prefixes in the Watch list, separated by blanks or commas. When a spot arrives starting any of these it will be highlighted in the list.
   3. You can set several arbitrary cluster commands. Those commands that are set On will be sent one time when HamClock logs into the node. HamClock will store all the commands for you, whether they are On or Off. Use the commands appropriate to the type of node you select. An intro to Spider commands is here and for AR-Cluster here.

      It is important to understand that cluster commands are saved on the node and remain in effect for the given login name even if you log out and log back in. It is not enough to just not send them to get the opposite effect. For example, suppose you want to reject all spots of US amateurs, you could enter this (spider) command and set it On:

                  rej/spot 0 call_dxcc 226
                  

      Because it is set On HamClock will send this command when it logs in. Now suppose you restart HamClock and just turn this command Off. This tells HamClock to not send this command when it logs in. That's fine, but since the cluster remembers your settings across logins, the filter will still remain in effect! To turn off this filter, you need another command to explicitly clear it, such as

                  clear/spot 0
                  

      Thus, it's a good idea to create pairs of commands, one to engage and one to cancel each filter type.
2. While in Setup, go to page 5 and choose the desired scrolling direction. You can also control whether spots are labeled on the map as complete call signs or just the prefix and whether and how the full path is drawn. Note that only the DX side is labeled since it rarely matters who exactly made the spot, just where.
3. Once HamClock is up and running, select the DX Cluster data pane in either of the two right panes. The name of the host will be shown in yellow while a connection attempt is in progress, then it will turn green when the connection is established. If the connection fails, it will show an error in red.
4. Once connected, just leave it run, new spots will be listed, scrolling when full. Tap on a spot to set HamClock's DX to that location. The tap can also set the frequency of your radio, see the User Guide for details.
5. HamClock stores several more spots than those listed; use the Up and Down arrows to scroll backwards and forwards through time. HamClock always adds new spots to the end of the list, but if you have scrolled away HamClock will not automatically scroll back to the beginning to show them. To ensure you will see new spots immediately, just make sure the opposing arrow is not drawn.
6. Beware: HamClock stays logged into the cluster node with your call sign as long as the DX Cluster data pane is visible. So do not use this feature if you want to use the unassisted category in a contest -- some judges do check!
7. HamClock can also use the DX Cluster pane to communicate with WSJT-X or JTDX. Instead of showing cluster spots, it shows each FT8 station you log. Details for doing this are in the User Guide.
8. HamClock enforces a limit of 10 server disconnects per hour. This was implemented at the request of cluster sysops to prevent HamClock repeating connection attempts endlessly do to the following situations:
   1. You have multiple software programs connecting to the same cluster using the same login.

      Clusters reject multiple simultaneous logins from the same callsign. So when HamClock connects with the same call in use elsewhere, the node disconnects, HamClock retries and this repeats continuously. The limit of 10 now prevents this. The solution is to use a unique suffix for each program, such as WB0OEW-1 and WB0OEW-2.

   2. You have set some nonsense cluster login, such as all blanks or NOCALL.

      The nodes also reject these, resulting in the same reconnect looping situation. The solution is to enter a valid call sign, perhaps with a suffix as above.

Yes. Use a browser to load the page live.html on port 8081 from the host running hamclock. For example, if HamClock reports its local IP as 192.168.7.101, then enter this URL to run it from your browser:

http://192.168.7.101:8081/live.html

Why would you use this?

• It's an easier alternative to VNC or remote X servers.
• It's an easier way to accomplish full screen compared to using xrandr.
• It allows displaying one HamClock on multiple monitors simultaneously for, say, a contest group.
• You can see and control HamClock with your phone.