wow man you have to lose R1 and R2…They are probably both open now anyway if they were 1/4 watt.
Why are they there?
I would also check your filter caps, C1 and C3, as they might not have recovered so well from a load like that. (something’s gotta pay when you flame up a wire like that, I would bet it was not just the resistors.) If you don’t just swap these parts you should at least check for excessive AC ripple on your DC output lines.
Best Regards
SmashTV
Hi Smash, thanks for your reply!
The resistors are in the schematic for some kind of protection, my first caps are rated 4700uF, my dad suggested that when using caps that big you need to provide a “load” to decipate the spiked generated by the trafo when turning the box on. I’ve measured the 9v circuit with and without the resistor, and it made no difference for the voltage.
The resistors are 3W and they come from his leftover military stash (must be over 40 years ago, when they still made stuff that could take a beating 
), I desoldered the one in the malfunctioning branch and measured it: it’s ok. I don’t know how to measure/check the caps, but they are rated 40V, I don’t think they’ve fried either. What I initially thought was that my rectifier had taken a beating as it only read 10v when being supplied with 8,5ac, but it seems that it needed a little time to recover, 'cause now everything is about fine again (thay way it used to be anyway).
I agree with smash, if r1 and r2 are supposed to be bleeder resistors then they would need to be at the output of the power supply.(worst case 13v/3000ohms=.0043A or .056W I don’t think the resistors blew). But there’s some other problems. The power transformer outputs 9 vac and 5Vac at the two secondaries. That’ll be about 12.6 Volts and 7 volts after the rectifiers. (it’s been awhile so correct me someone if I’m wrong) Full wave bridge rectification is the ac x 1.414. also in your circuit as shown above, you have a 9 volt regulator supplied with a 7 volt source, and a 5 volt regulator supplied with 12 volts, switch the secondaries or the regulators. Also the way the two supplies are built, they are separate entities, you have a ground wire connecting to both supplies via the led, pick one side or the other not both, although I don’t think this would cause a problem. More than likely you’ve gotten your gnds and B+ crossed somewhere and perhaps shorted the supplys’ outputs or wired them in series.
My buddy Willy once told me…
“Hey go for it, Chicks dig the sparks!”
Have Fun!
RoyalScam
Oops, the schematic is wrong ofcourse, switched the 78xx’s ;D /schematic fixed now.
The ground wire needs to be there according to moebius, who made that clear during some very cryptic posts, but I measured the stuff and the wire makes no difference for both branches. The LED is ofcourse not used to connect both branches, the LED is connected between +5v and ground, did I make another mistake in my schematic? the dot should mean there’s an interconnect between the 3 wires there, shouldn’t it?
What I’m really curious about, is how much volts I should actually read on the 9v after rectifying, it is indeed a full wave bridge. I still believe the one rectifier might be faulty…
(The official formula would be nice too, because the AC input is not exactly 9v and 5v, rather 8,5v and 5,7v. Constantly trying to learn…)
Thanks for your help guys, it’s appreciated!
Cheers, Alex.
