Hi all,
Another 'lockdown job' - just taken my A85 apart as it had blown the main input fuses. One channel of the SAP15s has blown, quite literally (surprise surprise), but my question is does anyone know what the turquoise heat sink sheet is ? The sheet is well and truly stuck to both the heatsink and transistors and will be destroyed when they are removed. I'd like to replace it like for like if possible so does anyone have any ideas who makes it ? It seems to be a turquoise plastic top layer with a grey under layer. Google has thrown up nothing.
Cheers,
Jon
Another 'lockdown job' - just taken my A85 apart as it had blown the main input fuses. One channel of the SAP15s has blown, quite literally (surprise surprise), but my question is does anyone know what the turquoise heat sink sheet is ? The sheet is well and truly stuck to both the heatsink and transistors and will be destroyed when they are removed. I'd like to replace it like for like if possible so does anyone have any ideas who makes it ? It seems to be a turquoise plastic top layer with a grey under layer. Google has thrown up nothing.
Cheers,
Jon
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It is isolation foil with good thermal conduction. Very common in grey, pink, blue. Most of the big distribs have it.
Resultats de la recherche pour : thermal isolation sheet Bergquist Company Produits d'interface thermique – Mouser Belgique
Jan
Resultats de la recherche pour : thermal isolation sheet Bergquist Company Produits d'interface thermique – Mouser Belgique
Jan
The service manual refers to the heat sink sheet as Kool Pad.
I would imagine this is the product
Aexit Silicone Thermal Heatsink Insulator Pads 0.35 X 300mm for Transistor Blue (58a15a95aef8118217898cafadd1e344): Amazon.co.uk: DIY & Tools
I would imagine this is the product
Aexit Silicone Thermal Heatsink Insulator Pads 0.35 X 300mm for Transistor Blue (58a15a95aef8118217898cafadd1e344): Amazon.co.uk: DIY & Tools
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This is the best; Thermal Interface Sheet, 1.6W/m*K, 150 x 150mm 0.5mm, Self-Adhesive | RS Components
This is less expensive but works extremely well; SPK10-0.006-00-104 | Thermal Interface Pad, Thin Film Polyimide, 1.3W/m*K, 25.4 x 19.05mm 0.152mm | RS Components
Lots to choose from; Thermal Pads | RS Components
Did someone fit the wrong fuses or short out the internal resistors I wonder.
This is less expensive but works extremely well; SPK10-0.006-00-104 | Thermal Interface Pad, Thin Film Polyimide, 1.3W/m*K, 25.4 x 19.05mm 0.152mm | RS Components
Lots to choose from; Thermal Pads | RS Components
Did someone fit the wrong fuses or short out the internal resistors I wonder.
Thank you all for your suggestions.
The Bergquist SIL Pads look good and RS do a silicone gap pad with up to 8W/m.K conductivity which shouldn't break the bank (too much).
Jon the Sanken SAP15 devices have a design flaw where the built-in emitter resistors tend to fail before the transistors themselves and the result, well, you can see for yourself stuck to my heatsink! For this reason I'm going to replace them with STD03 and external 0.22R resistors (when I can get hold of some Fukushima Futaba MPC74).
The Bergquist SIL Pads look good and RS do a silicone gap pad with up to 8W/m.K conductivity which shouldn't break the bank (too much).
Jon the Sanken SAP15 devices have a design flaw where the built-in emitter resistors tend to fail before the transistors themselves and the result, well, you can see for yourself stuck to my heatsink! For this reason I'm going to replace them with STD03 and external 0.22R resistors (when I can get hold of some Fukushima Futaba MPC74).
Conrad have the MPC74 in stock
Fukushima Futaba MPC74 5W 0,22 Ohm 5% Metal film resistor 0.22 Ω Radial lead MPC74 5 W 5 % 1 pc(s) | Conrad.com
Fukushima Futaba MPC74 5W 0,22 Ohm 5% Metal film resistor 0.22 Ω Radial lead MPC74 5 W 5 % 1 pc(s) | Conrad.com
Thanks 'Audio Service'
By the way for anyone else looking for them, RS also stock the MPC74 but they're currently on back order.
By the way for anyone else looking for them, RS also stock the MPC74 but they're currently on back order.