I didn't realize it, but my '72 Dodge has a switching power supply to convert the 12 volt system voltage to 5V for the dashboard instruments.
It's a very simple device, relying on current heating a wire to bend it to and from a contact, but it's an engineering marvel of low cost effectiveness.
But it doesn't produce "clean" 5V, there's a jitter to it. Some electronics guys have replaced it with modern circuitry (an op-amp I think) but it turned out there was a problem with clean 5V. The jitter would unstick the the analog dials, so they'd display accurately. The clean 5V didn't do that. So, they had to add more circuitry to add jitter in the supply voltage.
It's a very simple device, relying on current heating a wire to bend it to and from a contact, but it's an engineering marvel of low cost effectiveness.
But it doesn't produce "clean" 5V, there's a jitter to it. Some electronics guys have replaced it with modern circuitry (an op-amp I think) but it turned out there was a problem with clean 5V. The jitter would unstick the the analog dials, so they'd display accurately. The clean 5V didn't do that. So, they had to add more circuitry to add jitter in the supply voltage.