When the original thermal turn signal flasher gave up, I replaced it with an electronic flasher. With the engine off I can hear it clicking very clearly – I can’t hear it while the engine is running unless the fuse box is open and I stick my head next to it – not a good driving position since the fuse box is just above the floor.
Probably 40 years ago, I made a turn signal amplifier using a 555 integrated circuit and a Mallory Sonalert. It was annoying, sort of like the beepers that some vehicles have when they’re backing up.
I started looking for a brighter lamp for the turn signal indicator that is mounted below the tachometer. The OEM lamp is a 74 Miniature Indicator Lamp – 14 Volt – T1-3/4 Sub Mini Wedge Base. In bright sunlight, it’s difficult to see if the OEM lamp is flashing. I found an LED replacement lamp that is essentially a SMT LED stuck on the end of a plastic tube with a diode and resistor to drop the voltage. It had the necessary wedge base. I had to file the sides down a little so it would fit in the lamp holder, but it was worth the $5.50. It’s bright enough to see in direct sunlight, but not so bright that it’s too annoying at night.