Self-combusting Speccy

From: Iggy Drougge <>
Date: Mon Oct 22 18:41:19 2001

Tony Duell skrev:

>> So I find this nice little program called "Toot", which "toots" Spectrum
>> snapshots into the earphone socket of said machine.

>I assume this involve a direct connection from a PC soundcard to the
>Speccy. Do you know if your PC is properly grounded? Do you know if
>either side of the Speccy PSU is grounded? Could you have shorted
>something out (or worse, applied half mains voltage across the Spectrum)
>via the ground connections

Actually, it would involve an Amiga, no PC. =)
The Amiga is routed through a "sound enhancer" (some filters to make the sound
crisper) into an amplifier, and the tape output of the amplifier would go into
the Speccy earsocket.
Only I never got that far. The Speccy started smelling before I ever got as
far as tuning into its RF signal or plugging it into the stereo.

>> What happens when I plug the machine in? A hideous smell, that's what. Now
>> I'm back at square one. No working Speccy. All I get is a black screen.
>> When fine- tuning the receiver, the border is sometimes visible. Is there
>> something irreplacable, like the ULA, which has broken, or is it the CPU
>> (I've got plenty of those) or just some discrete component?

>The most common problem (or so I am told) on early Spectrums is the
>transistor in the PSU converter circuit. It generates at least one of the
>supply lines for the DRAM. I would start by checking the power supply
>voltages at the DRAM pins.

Thank you, I'll do that as soon as I get to a multimeter.
It's rather nice that the system is so simple that there isn't a whole lot of
modules with various dependencies which may fail resulting in different

En ligne avec Thor 2.6a.
You can have SEX with a Dragon but not with an Apple.
  -- Tony Duell
Received on Mon Oct 22 2001 - 18:41:19 BST

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