It depends, if the transformer has dual 115V primaries, you may have to put them in parallel for 115V input. The manufacturer's datasheet should make this clear. It's not very common to leave one primary floating for 115V. Also, if it has dual secondaries, you can put them in parallel as well. That way you can take full benefit of the transformer's rating.
The rating of the fuse is based on the rating of the transformers that you use. Look at the total VA rating of all the transformers that you use in your DAC. Divide the sum by 115V, and this gives you the nominal current. In this case, choose the fuse rating the same, because you will not be fully loading the transformers. Because they form an inductive load, always use a slow-blo fuse.
Ray
The rating of the fuse is based on the rating of the transformers that you use. Look at the total VA rating of all the transformers that you use in your DAC. Divide the sum by 115V, and this gives you the nominal current. In this case, choose the fuse rating the same, because you will not be fully loading the transformers. Because they form an inductive load, always use a slow-blo fuse.
Ray
That's the wrong transformer.
I've picked up the Antek - AN-0115 for the opamps
and
Antek - AN-0112 for the 9v sections.
I've picked up the Antek - AN-0115 for the opamps
and
Antek - AN-0112 for the 9v sections.
. This goes for all of them!
Yes, plenty of suggestions 
You have to use all three AC inputs of the ezDual to make it work. Connect the two 15V windings in series, green to blue, and connect this junction or centre tap to AC2. Connect the remaining green and blue wires to AC1 and AC3, which goes to which doesn't matter. Should work now! Primaries go in parallel.
Regards,
Ray
You have to use all three AC inputs of the ezDual to make it work. Connect the two 15V windings in series, green to blue, and connect this junction or centre tap to AC2. Connect the remaining green and blue wires to AC1 and AC3, which goes to which doesn't matter. Should work now! Primaries go in parallel.
Regards,
Ray
http://docs.google.com/Doc?docid=0AWdaOT0Wdk2oZGY4YzM5amtfMzBjcHI3dmJkaw&hl=en
Here's how i got it hooked up. I'm getting ~ 15vac between ac1 and ac3/ and ~ 15vac between ac3 & ac2.
about ~32vac between ac1 and ac2.
Here's how i got it hooked up. I'm getting ~ 15vac between ac1 and ac3/ and ~ 15vac between ac3 & ac2.
about ~32vac between ac1 and ac2.
Is the voltage across C1b and C2b lower now? Most voltage regulators have an over-voltage protection, and they shut down if the input voltage is too high. Could be the case if it's still >40V. If it's more in the region of 25V, then it's o.k. The actual value is not very important, because it's the no-load voltage, and it depends on the no-load behaviour of the transformer. If the output is still +/- 7V, try loading them with a 1k resistor and see if the voltage comes on. R3 and R5 are quite large (240R) and therefore the minimum load current spec is not met. Voltage across R3 and R5 should be around 1.25V at all times.
Ray
Ray
Waaait a minute... did you use 240 ohm and 1k1 according to the BOM on ezdiyaudio.com? No wonder you only get +/-7V! Wrong values! Duh!
For +/-15V output, change R3 and R5 to 100 ohm, that should do the trick!
Ray
Ok, yup I used the BOM on ezdiyaudio.com. What's the colour code for 240 ohms? I'll have to check it out when I get home and replace them.
Thanks,
JG
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