Apple III can’t tiping on prompt

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Apple III can’t tiping on prompt

hi guys, let me start by saying that I really have zero knowledge of Apple III, I bought an Apple III and replaced all the capacitors on the power supply, the machine turns on and the word retry appears, if I try to detach the keyboard it loops in a diagnostic ram (I don't know if it's normal), seeing some videos however by pressing ctrl + apple open an arrow appears and then I can write, I tried to press the same combination too and the arrow appears and you hear a beep but it doesn't allow me to write anything, it's a malfunction I assume, does anyone have any suggestions?

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Booting the A III

Retry means it didn't find a boot disk. Does the internal drive spin/seek at power on?  The -> (arrow) means you got into the monitor. You should be able to type something like ff00.ffff (then press return) to see a short hex dump of the rom. There is no built-in BASIC like the Apple II's have, so you always need a disk in the internal drive.

 

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 yes the unit runs for a few
 

yes the unit runs for a few seconds, I also tried to put a game on, the word apple sos comes out and then after a while of loading I get I/O error, as far as after the arrow I can't digital anything, whatever keyboard key I press doesn't work, the dash flashes after the arrow so it's not locked

 

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No keyboard

Make sure the power light works - there is a small "on" indicator between the closed/solid apple key and the space bar. If this doesn't light up, the system does not think a keyboard is connected. If the light is functional, you may have to look into replacing the keyboard encoder chip.

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yes the keyboard is powered,

yes the keyboard is powered, as I wrote above the reset keys work as well as the ctrl and open apple keys, everything else seems dead, so the encoder is dead I presume?

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None of the modifier keys

None of the modifier keys (like control, reset and the apple keys) go through the keyboard encoder. Although there may be other chips that could cause this kind of failure, I have heard the original encoder chips are fairly static sensitive. Joe's Computer Museum (jcm-1.com) sells a "Universal Keyboard Encoder" module. Beyond this, I have no further suggestions.

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I'll try to measure if the

I'll try to measure if the correct voltages arrive at the encoder, if the -12 and 5 volts arrive correctly I'll buy a universal encoder

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