20 Most Recent Panasonic SC-AK78 CD Shelf System Questions & Answers

Need to know how to get rid of F-61, cause my stereo is completely dead...model# SA-AK78

STK-470-040 ic is blown and needs to be changed.

F61 usually means the amp has detected a short or a severe microprocessor error.


Generally speaking, an amp attempts to protect itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.

Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

If it protects immediately on a cool power up you should disconnect the speaker connections and try it 'naked'. If it comes up then diagnose which lead(s) are shorted. If it does not come up the problem is internal and should be left to an experienced and competent hands-on tech.

You may have the same problem as I had..broken solder joints on power amp board..namely the power relay.

This is a sign of a power supply problem. These units use what is called a "switch mode" power supply. These use a capacitor to kick-start the power supply. While I can't say for sure, this is the most likely cause. There are other components that can be close to failure later in the circuit that can cause this as well. Without seeing the actual unit and testing the circuits, there is really no way for me to know. You should expect to pay in the $20 range for parts for this repair.

Dan

Generally speaking, an amp attempts to protect itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.

Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

If it protects immediately on a cool power up you should disconnect the speaker connections and try it 'naked'. If it comes up then diagnose which lead(s) are shorted. If it does not come up the problem is internal and should be left to an experienced and competent hands-on tech.

Check for loose speaker connections at the speaker as a root cause for intermittent shutdown.

Have a Panasonic SA-PM53 pulled a CD trays out to get stuck CDs out. So how do I get the 5 CD trays back into the carriage and in sync?

keep pressing display demo button for sometime.it will show no demo and you're done

ic STK 470-040 is blown

Stk 470-040 ic is blown and need to be replaced at service cntr.