Unloaded transformer voltages help

[sethyrish]

I've finally finished a rocket I started 2 years ago. 1st amp build and the unloaded voltages for Classic Tone 40-18065 are:
477v
17.2v ??
and 6.3v
Are these normal or is it the Australian mains supply?
The transformer is 50/60hz 240v
I don't want to blow up my amp after such a long wait!

http://members.iinet.net.au/~tinasime/amp.jpg

http://members.iinet.net.au/~tinasime/DSCF1011.jpg

http://members.iinet.net.au/~tinasime/DSCF1009.jpg

[martin manning]

When you say unloaded do you mean with no tubes installed? How are you measuring these voltages? To ground, or across the secondary windings?

What do you get for mains voltage if you measure across the primary?

[pdf64]

http://www.classictone.net/40-18065.pdf
Just to expand on the above, it would be beneficial for you to note the voltage applied to the primary, which wire colours you have connected it to, any links (eg blk/wht to brn), and what voltages you are getting on the secondaries across which wire colours.
Pete

[sethyrish]

Volts to earth are:
270 for the 300v
244 for 260v
72v for the 5v to ground
and 5v across.

The only wires connected are the white 6.3v center tap to
to pin 3 of EL84's
and red and yellow 300v/260v certer tap to the Earth.

http://members.iinet.net.au/~tinasime/C ... -18065.jpg

Thank's for your help.

[martin manning]

What is your mains voltage? I'm guessing it's low since your high voltage windings are low.

Note the 5V winding is floating with no ground reference, so the measurement to ground is useless. The others are grounded at their CT's so those voltages are good (as long as your meter is accurate).

[sethyrish]

Yes your right. It was 219v

[sethyrish]

So it all looks good to progress to next stage then?

[martin manning]

Sounds good to me. I'd put just the rectifier in and check for DC voltages along the power supply rail at this point. You could use a bulb limiter, but if you measure resistance from the rectifier pin 8 to ground and get tens of thousands of ohms, with standby on or off, you are probably safe.

[sethyrish]

Cheers

I've made myself a bulb limiter especially for the occasion.
Thanks for the pointers.