No. Don't check it before each flight. That runs the battery down, and most ELTs have a limit on such testing because of that. Moreover, testing an ELT is only legal if the thing is connected to a ballast instead of an antenna and is inside an RF box so ATC doesn't hear anything. Mechanics often test an ELT but
only between the hour and five after the hour, such as 11:00 and 11:05, and the transmission has to be limited to just a few seconds. There are fines for operating one illegally. It's not ok to be testing it in flight, either. And running a transmitter without an antenna load can damage it.
From
https://www.cfinotebook.net/notebook/avionics-and-instruments/emergency-locator-transmitter We read:
Testing Emergency Locator Transmitters:
- ELTs should be tested in accordance with the manufacturer's instructions, preferably in a shielded or screened room or specially designed test container to prevent the broadcast of signals which could trigger a false alert
- When this cannot be done, aircraft operational testing is authorized as follows:
- Analog 121.5/243 MHz ELTs should only be tested during the first 5 minutes after any hour. If operational tests must be made outside of this period, they should be coordinated with the nearest FAA Control Tower. Tests should be no longer than three audible sweeps. If the antenna is removable, a dummy load should be substituted during test procedures
- Digital 406 MHz ELTs should only be tested in accordance with the unit's manufacturer's instructions
- Airborne tests are not authorized
False Signals:
- Caution should be exercised to prevent the inadvertent activation of ELTs in the air or while they are being handled on the ground. Accidental or unauthorized activation will generate an emergency signal that cannot be distinguished from the real thing, leading to expensive and frustrating searches. A false ELT signal could also interfere with genuine emergency transmissions and hinder or prevent the timely location of crash sites. Frequent false alarms could also result in complacency and decrease the vigorous reaction that must be attached to all ELT signals
- Numerous cases of inadvertent activation have occurred as a result of aerobatics, hard landings, movement by ground crews and aircraft maintenance
- These false alarms can be minimized by monitoring 121.5 MHz and/or 243.0 MHz as follows:
- In flight when a receiver is available
- Before engine shut down at the end of each flight
- When the ELT is handled during installation or maintenance
- When maintenance is being performed near the ELT
- When a ground crew moves the aircraft
- If an ELT signal is heard, turn off the aircraft's ELT to determine if it is transmitting. If it has been activated, maintenance might be required before the unit is returned to the "ARMED" position. You should contact the nearest Air Traffic facility and notify it of the inadvertent activation
Inspections & Tests:
- An emergency locator transmitter (ELT) is required by 14 CFR, part 91, section 91.207, and must be inspected within 12 calendar months after the last inspection for the following:
- Proper installation
- Battery corrosion
- Operation of the controls and crash sensor
- The presence of a sufficient signal radiated from its antenna
- The ELT must be attached to the airplane in such a manner that the probability of damage to the transmitter in the event of crash impact is minimized. Fixed and deployable automatic type transmitters must be attached to the airplane as far aft as practicable. Batteries used in the ELTs must be replaced (or recharged, if the batteries are rechargeable):
- When the transmitter has been in use for more than 1 cumulative hour
- When 50 percent of the battery useful life or, for rechargeable batteries, 50 percent of useful life of the charge has expired
- An expiration date for replacing (or recharging) the battery must be legibly marked on the outside of the transmitter and entered in the aircraft maintenance record
- This does not apply to batteries that are essentially unaffected during storage intervals, such as water-activated batteries