The "digital" radios in this house all have a battery in them to maintain the settings, but can not be set to start up on power-on. Two DO have an "alarm" setting that will turn the radio on at a set time. If you use a timer to turn the radio off and on you need to make sure the timer comes on before the alarm time. The battery also keeps the realtime clock running with the power off.
That isn't restricted to a digital radio. It's any device that has a sleep mode or standby power mode. IE: anything that doesn't have a real power switch. The momentary push button switches on modern tv sets aren't controlling high voltage ac mains directly; they're telling another circuit board that's using a small amount of power that it's okay to close a relay to bring the main power board online from the ac mains. And it'll hold the relay closed until you press the little button again, which opens the relay and resumes sleep/suspend/standby mode.
Most of the time, the power switch is controlled by another board entirely that's mostly a small transformer, a few circuits, a relay and access to the hot leg of the ac mains that it passes along via a closed relay to the rest of the set that does the real work. When you push the button to turn the tv off, it opens the relay. When you want it on, it closes the relay. The remote on the tv is doing the same thing. Sometimes, the IR LEDs are on the smaller standby board and other times it's located on their own boards wired to it, or might be sitting on the actual mainboard of the set, but electrically connected only to the standby board; it just has a physical residence on the mainboard.
So, there's nothing for it to memorize, and no way to enforce the memorization if it did, as the standby board is entirely reliant on human interaction for relay open/close.
The only exception are sets that have additional circuitry to trip the standby board into closing the relay with pulse signal; this requires additional circuitry on the standby board as well as mainboard of the set, wiring, additional coding frontend/backend, and, space to store the last known 'setting' to enforce when the standby board has access to ac mains power.
The additional circuitry on the standby board serves to provide a limited amount of power to the mainboard without closing the relay so the mainboard can pull the last known setting and tell the standby board to close the relay, if that was the setting. When it closes the relay, that's when it's connecting ac mains (the hot leg) to the main power supply that actually runs everything else. The standby board has it's own power supply that's always hot if the set is plugged in.
Yes, exactly.
I have a small tv but for various reasons, can't use it.
I'm set up now, though. Thanks all.
Or a "smart" tv with auto turn on - - - does not need to be a real "smart tv" with internet connectivity - just power saver or timer start - or some that revert to power on on power up. (just like some computers) My ancient Panasonic Viero PT700 has the capability to start and stop by itself
Ted Kennedy's Oldsmobile has killed more people than my handguns.
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