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Philips receiver 70FR260 does not wake up

Hi,

I am trying to repair a Philips receiver 70FR260 or FA260. It had shorted clamp diodes and open control transistor for the power relay. I replaced them, but still the microcontroller does not wake up. If I pull down the micro output, the power relay turns on the set. All supply voltages are present but the display is dead. Also removing the back up batteries for a while didn't help. The micro controller oscillator is running, all of its signals seem to be ok, including the key scanning pulses. So its program is probably running. I would appreciate suggestions to wake up this stubborn receiver!

Best regards,

Gerhard

Reply to
Gerhard
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What about the reset line to the micro?

Mark Z.

Reply to
Mark D. Zacharias

"Mark D. Zacharias" schreef in bericht news:P2Iij.4435$ snipped-for-privacy@newssvr22.news.prodigy.net...

Mark,

Thanks for your response. The /res line is high when the supply voltage is present and is pulled down as the supply voltage drops. So I don't think the reset line is the cause.

Best regards,

Gerhard

Reply to
Gerhard

Had a Denon recently which looked like a bad micro - a bad PLL chip on the tuner board was pulling down a data line. You could try unplugging some of the peripheral boards and see if that allows the display to come up. Of course the micro itself could be bad, you may just have to replace it to see.

Mark Z.

Reply to
Mark D. Zacharias

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