Hi there TV TECH,
Well, it is better than using one cap, but still not a complete isolation. AC can flow through either cap to ground because with the DC circuit in there we'll have some AC potential to both the negative side and the positive side. The potential will be about halved, so it's a little better...60v instead of 120v, as long as nothing else happens.
There still remains the transient problem too. With the cap uncharged, the total potential that can reach the top side cap output is still 170/2 volts peak to ground. If everything was working properly it would be 170/2 volts minus 6 volts, and on the bottom side cap the same.
So the circuit is still only isolated for DC, and since the mains supply is AC there's still a big safety issue. It's workable, but still an important issue.
Well, it is better than using one cap, but still not a complete isolation. AC can flow through either cap to ground because with the DC circuit in there we'll have some AC potential to both the negative side and the positive side. The potential will be about halved, so it's a little better...60v instead of 120v, as long as nothing else happens.
There still remains the transient problem too. With the cap uncharged, the total potential that can reach the top side cap output is still 170/2 volts peak to ground. If everything was working properly it would be 170/2 volts minus 6 volts, and on the bottom side cap the same.
So the circuit is still only isolated for DC, and since the mains supply is AC there's still a big safety issue. It's workable, but still an important issue.
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