Hi. Hope this thread is kosher. Unless I do build a power supply in the end, I may want to purchase a power adapter or unit for a tuner board I have (from a Pioneer F-X77ZL). I'm guessing that board will not take more than 10W. I can identify some power adapters for sale, but I don't think I've yet come across one, or a type, that would be suitable for this tuner board. The adapter or unit needs to have pretty good ripple specs. I'm not sure whether I strictly need a linear unit or not. Are there suitable power adapters or units out there for sale that would be suitable for my tuner board? Thank you. I'm in UK. Rich EDIT: I'm in process of trying to buy a service manual for the F-X77ZL so I can glean wattage and supply voltage.
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Attached is the service manual for the Pioneer DC-X77Z, which contains the power supply for the F-X77ZL tuner. On the schematic you can see that the tuner needs 12 Vdc.
The 12 Vdc is taken from a rail that consumes 420 mA. Even when all of that 420 mA would go to the tuner (which is certainly not the case) the tuner would be consuming at most P = I x V = 0.42 x 12 = 5 Watt from this supply.
There's also an AC voltage going to the tuner, taken from the centre tapped secondary of the power transformer. I estimate the voltage at the transformer to be around 25 Vac, but since there is 600 Ohm of resistance (R164 + R165) in the lead to the plug and since I don't know how much current the tuner is taking on this connection, I can't calculate the required voltage at pin 9. But maybe (or probably?) this AC voltage is for dial lamps or something like that so if you only want to operate the circuit board of the tuner you maybe (or probably?) don't need that AC voltage.
Im not very into adapters so I can't advise you on that one. Maybe it's best to get your hands on a adapter that gives of a higher voltage (18 Vdc) and than use a voltage regulator (like for instance a L78S12C) so that you are sure your 12Vdc is clean.
The 12 Vdc is taken from a rail that consumes 420 mA. Even when all of that 420 mA would go to the tuner (which is certainly not the case) the tuner would be consuming at most P = I x V = 0.42 x 12 = 5 Watt from this supply.
There's also an AC voltage going to the tuner, taken from the centre tapped secondary of the power transformer. I estimate the voltage at the transformer to be around 25 Vac, but since there is 600 Ohm of resistance (R164 + R165) in the lead to the plug and since I don't know how much current the tuner is taking on this connection, I can't calculate the required voltage at pin 9. But maybe (or probably?) this AC voltage is for dial lamps or something like that so if you only want to operate the circuit board of the tuner you maybe (or probably?) don't need that AC voltage.
Im not very into adapters so I can't advise you on that one. Maybe it's best to get your hands on a adapter that gives of a higher voltage (18 Vdc) and than use a voltage regulator (like for instance a L78S12C) so that you are sure your 12Vdc is clean.
