Help with installing a LM386 Module 20 Times Gain Audio Amplifier Module F Raspberry Pi Arduino, on to a ZX board

Discussions about Sinclair ZX80 and ZX81 Hardware
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1024MAK
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Re: Help with installing a LM386 Module 20 Times Gain Audio Amplifier Module F Raspberry Pi Arduino, on to a ZX board

Post by 1024MAK »

Sorry, it’s hard to tell. Strangely audio amplifier manufacturers don’t design amplifiers or provide specifications for use with 1980s home computers…

Can you hear the loading sounds from the internal speaker in the Spectrum that is not loading?

If however it’s working fine with one Sinclair computer, then it does make me wonder if your other computer has a fault.

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Re: Help with installing a LM386 Module 20 Times Gain Audio Amplifier Module F Raspberry Pi Arduino, on to a ZX board

Post by petercushion »

Yes, you can hear the internal speaker, so I'm guessing the amp is working but the screen just stays grey. I loaded Jet Set Willy on the working Spectrum and it makes the same sounds as the Spectrum that isn't working when its loading apart from after about seven seconds the tone changes and then goes back to the loading sound like an old modem.

I've just now tried it without the amp and it makes exactly the same noises, so I guess it could still not be amplifying the sound enough.
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