1) SELECTING A RECTIFIER BRIDGE
It doesn't matter if the rectifier is rated at a higher voltage or higher current than you need. Go for the cheapest.
[2) SMOOTHING CAPACITOR
Yes an extra capacitor will smooth out the power. Not sure if that that circuit needs it, you are unlikely to do any harm by trying it without. If it does need extra smoothing something rather larger than the 220 already there will be needed
3) VOLTAGE DROP?
12 volt relays usually work down to around 8 or 10 volts depending on type so quite likely it'll work.
If you have a bridge rectifier to produce the DC, the 1N4001 diode at top right appears to be redundant, getting rid of that diode looks like the simplest thing to do to reduce the voltage drop.
4) VOLTAGE REGULATOR?
That would smooth out the power, but introduce a further voltage drop. You'd be pushing your luck with a 12 v relay.
Reed switches are simple to understand. Cars with traction magnets should work them OK, without magnets some people have made them work, some haven't
It doesn't matter if the rectifier is rated at a higher voltage or higher current than you need. Go for the cheapest.
[2) SMOOTHING CAPACITOR
Yes an extra capacitor will smooth out the power. Not sure if that that circuit needs it, you are unlikely to do any harm by trying it without. If it does need extra smoothing something rather larger than the 220 already there will be needed
3) VOLTAGE DROP?
12 volt relays usually work down to around 8 or 10 volts depending on type so quite likely it'll work.
If you have a bridge rectifier to produce the DC, the 1N4001 diode at top right appears to be redundant, getting rid of that diode looks like the simplest thing to do to reduce the voltage drop.
4) VOLTAGE REGULATOR?
That would smooth out the power, but introduce a further voltage drop. You'd be pushing your luck with a 12 v relay.
Reed switches are simple to understand. Cars with traction magnets should work them OK, without magnets some people have made them work, some haven't
