Ex Provideo professional broadcast equipment - Eurocard (DIN41612) format
Very useful, high quality Australian built power supply
ProVideo Rack Module Power Supply
Plus & Minus (dual rails) 10V & 20V unregulated outputs
Linear technology - NOT switchmode
Linear power supplies are often much preferred over SMPS technology in critical audio/video equipment due to their very low noise/ripple etc (if designed properly)
Harbuch (Sydney designer/manufacturer) toroid transformer
Toroid type: PTT 4408
This transformer is capable of providing 28V AC at 3 Amps AND 8.1V AC at 6.5 AMPS
It does have additional primary taps, easily convertible to 110 V AC operation.
The Harbuch transformer provides "raw" Low Voltage AC into a standard rectifier/filter capacitor arrangement
Filter capacitors are high reliability Samhwa (Korea) 85 degree 10,000uF each (four of them, one sits across each DC rail)
This unregulated DC is then presented to the daughter board that plugs into the DIN41612 connector on the end of the PSU - this daughterboard would normally be at the rear of the Eurocard frame and has the IEC 240V external power socket fitted.
A special addition on this daughter board is 4x Philips PBYR1545CT Schottky barrier diodes, one for each supply line.
These DO NOT provide any regulation of the DC voltage (that is normally undertaken at the individual card level) but these diodes have the enhanced characteristics of
• Low forward volt drop
• Fast switching
• Reverse surge capability
• High thermal cycling performance
• Low thermal resistance
The DC outputs are then all presented on the green connector (screw down type) which can be modified for custom use.
The measured DC outputs (no load) were
Red/Black/Red 11-0-11 DC volts
Blue/Black/Blue 21-0-21 DC volts
On the front panel of the module are two green leds, these are very simple "DC rail OK" type indicators - although marked as 5V and 12V this refers to the actual voltages on the modules, but they are powered from the 10V and 20V supply rail via zeners.
Compact linear power supply (low noise) for someone using the Eurocard frame systems for R&D or production prototyping etc
