From a 2003 Carlsbro 8400 , 400W mixer amp that immolated itself. Anyone have a schematic or parts listing. Assuming that Q319 is a high voltage TO92 2N5551 ( totally burnt and erupted but 2 isolated lighter blobs on the remnant of TO92 face are in the position of the isolated printed 2N of other 2N5551s on the board) then the melted blob component goes from the base of this feedback transistor to the speaker output line via the relay. So probably something like 47K 1/3W resistor. The board is also burnt so overlay for this blob also missing. Anyone ever come across a metal oxide resistor melted to a 3mm diameter blob like a small tantalum. Metallic grey blob that measures 40 to 150 ohm or so across diameters. The thermal heatsink monitor tranny was also exploded but as the face was gooed to the heatsink, that face was spared from charring/shattering and that was 2N5551 also.
You'd think Carlsbro would know better. The subframe inside the chipboard casing is held to the chipboard with 12 x
4mm bolts, yes machine screws screwed into chipboard, not even ordinary woodscrews, let alone proper twin-start long pitch chipboard screws. 2 had dropped out and because you carry this kit vertically but use horizontally, plenty of chances for 1 inch long steel screws to roll into the power amp. Audience were treated to piles of smoke erupting from the back of the amp - Hendrix was more impressive.Plenty of other damage but identifiable components for the others. Do you get a sensible response from technical email enquiries to Carlsbro and do I mention about their crass construction methods. ?
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on