Caledonian Audio Phono Classique, Assembly Manual

Page: 37 / 48

Caledonian Audio
Phono Classique Assembly Manual
37
37
1. To chassis safety earth ground point
2. To the Integrated PSU PCB 0V point
3. To phono preamp PCB 0V point (labelled T/T GND)
4. To left and right audio RCA connector negative terminals
You should now have something like Figure 32.
5 Powering Up for The First Time
There are a number of items that you have to prepare/gather before powering
up the amplifier for the first time.
CAUTION– Valves can reach very high operating temperatures when in
use and can cause burns if touched.
Please see the checklist below:
No. Item Note Done?
1 IEC power cable For powering up the system
2 Fuse For 220/230/240 (UK/Europe) version, a
slow blow 0.5Amp fuse is needed. This is
installed in the IEC socket.
(1A in US).
3 Safety ground Check the resistance between the earth
pin on the IEC socket and all grounded
metal parts on the amp. They should read
less than 0.1 ohms.
4 Variac It is highly recommended to use a variac
which will allow you to slowly bring up
voltage to the amplifier system
5 Light bulb
current limiter On top of the variac, it is also
recommended to use a simple light bulb
current limiter. This is to keep an
accidental short in the amp from pulling too
much current and blowing a fuse or
possibly doing damage to transformers.
6 Power up
without valves It is highly recommended to power up the
amplifier without the valves first and check
that the power circuit is stable (i.e. nothing
smoking or fuse blowing).
One can check the B+ and heater voltages
now but bear in mind that without any load
the voltages will be much higher than
stated in the schematics diagram
7 Normal power
up and voltage
readings Once all above have been noted/done, you
can power up with the valves connected.