Blocking Diode and Zenor Diode (shunt)

hmlittle59

I have a my Custom board built around the BS2e...Board is 4x3, (Shift register, DS1302, SSR(3), Resistors). Whats the thought(s) of using a Polarity Blocking Diode and 7.5 shunt Diode to limit the voltage? My first Board was thru hole and I used a NTE 073H 5 vdc 1.5a regulator. The wal mount was 15 volts and need less to say the Voltage regulator got very very hot...(da). Now I'm worried about protection, once I realized the problem, I dropped it down to 8 volts and now....coooool to the touch.

I've noticed the BOE doesn't use them.

Whats EVERYONE's thoughts.....?? thanks

BLOCKING and SHUNT Diode combo on the INPUT.

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I'M STILL LEARNING SO MUCH...BUT STILL KNOW SO LITTLE!!!

hmlittle59