Theres no memory to the clock and radio settings

if the unit only looses radio station presets then there is a defect with the unit. if the unit looses all its memory, (clock, stations, settings) then there is an issues with your aux power. basically you have the main power connect properly so it turns on the unit while the cars is on but the aux power keeps those settings.

When you find a frequency that you
want to store in memory, press one of pre-
set tuning buttons 1through 6 and hold until the
preset number stops flashing.
The number you have pressed will flash in the
preset number indicator and then remain lit.
The selected radio station frequency has been
stored in memory.
The next time you press the same preset tun-
ing button the radio station frequency is re-
called from memory.

Have you inserted 2 x AA batteries in the back where you charge the Dewalt batteries? there is a cover with a black phillips screw, this is where the AA batteries go for the memory clock & radio presets.

setting stations on Fords are easy,put it on the station you want to program and push the channel button in and hold for about 2 seconds then it should flash,now the channel is set..now for the clock,with the key on and radio turned off,press the clock button,then press the seek or scan forward or reverse to adjust the time,then hit the clock button again to make sure it sets.

Here is the full manual
http://www.timexaudio.com/pdf/T311IB57574_35.pdf

Here are the instructions from the manual.

Setting the Radio Alarm
1. Press and hold the
Radio Alarm Button. The display will flash and the Radio Alarm Indicator will
appear. If you do not begin setting the time within ten seconds of pressing the button, the display will stop
flashing and you will need to press the
Radio Alarm Button again.
2. While the display flashes, press the Reverse and  Forward Buttons to set the wake time. Hold a button
for a few seconds to set the time rapidly. Be sure to set the correct AM/PM time, as shown by the PM Indicator.
3. After setting the radio alarm time, you will need to select the station. First, press the  Radio Band Button
to select a radio frequency. Next, select a station using the Memory Set 1-6 Buttons. For more
information on programming radio stations into memory, see the Programming Radio Station Settings section
of this manual. Rotate the  Volume Thumbwheel to set the wake sound volume.
4. After setting the radio alarm wake time and sound, you will need to select the 7-5-2 setting. The 7-5-2 setting
lets you set the alarm for a full week, weekdays only, or the weekend. Before setting the alarm, be sure that
the correct date is set, as shown in the “Auto-Set” and Manual Time and Date Settings section of the manual.
While the display is still flashing, press the  Date/7-5-2 Button until the desired setting is shown.
5. After you have set the radio alarm wake time, sound, and 7-5-2 setting, press the  Enter Button. The
Radio Alarm Indicator will appear on the display, showing that the radio alarm has been set.

You have a blown fuse for the memory for the radio & the clock.

The radio was improperly installed; there are two 12V leads, one services the radio when on, the other, only the circuitry for the clock and presets.
Eventually, this shouldn't be needed if the manufacturers ever think about using a little bit of flash memory for the presets and a coin cell for the clock.

You didn't give any model number so researching the manual is impossible.
If you can find the model number, look for a user's (or installation) guide on line to find the wiring info.

to set the 5 main presets:
with radio on, use the manual tuner to find station you want on a preset. push and release mem/clock adj button (mem will flash on display), push preset number and while holding it in push the mem/clock adj button again (mem on display will go away). station is now preset to that number.

to set the 5 additional presets:
with radio on, use the manual tuner to find station you want on a preset. push and release the +5 button (+5 will flash on display), push and release mem/clock adj button (mem will also flash on display), push preset number and while holding it in push the mem/clock adj button again (mem on display will go away). station is now preset to that +5 number.

to set the digital clock display:
with radio off, push and release the mem/clock adj button (clock display will now flash), use the tun up / hr part of manual tuning button to adjust hour and the tun dn / min part to adjust minutes.

Using the tuning buttons, select your station. Then press memory, select the station call#, and then press memory once again.

Set the station you want to wake up to in the "AL" preset memory. You can download the manual from the link below: http://157.254.235.130/public/rp3722.pdf Please update the question & let us know if the information given was useful to you - Good Luck!