heatsink and other

Referring to the Aleph 60 Service manual, the power consumption is 220W per channel.. This means you have to dissipate 110W per heatsink.

110 * 0,35 + 25 = 63,5ºC (38,5º above ambient)
That is a little too hot.
The original Aleph runs at 25º above ambient.

I'm using a 0,17K heatsink per channel for my Aleph 30.

R19 is marked 5622 ohms in the service manual, but that can't be right. It should have higher value.. I don't know the correct value though.



2001-10-31 10:52 pm
About not using an thermistor

If you don't use an thermistor in series with the primary of the transformer you'll get an increased inrush current. Depending on the size of the transformer and filter capacitors the inrush current may cause a blown fuse.
Amplimo (manufacturer of toroidal transformers in Europe) suggests the use of two 5Ohm thermistors (NTC-resistors) in series with the transformer if it's rated above 500VA.