I have a 4S which I successfully repaired by changing the CPU (not the same 4S as in my previous topic). I tried loading Bubble Dizzy from my Sony cassette deck, but partway through loading, the Spectrum returned to the copyright screen. I powered off, plugged in a Retroleum X-ROM card, and ran some tests. All RAM and the internal ROM are working. Partway through the lower RAM refresh test, the display changed to some wavy grey lines, and this is now all that I can get from this machine. The X-ROM will now not run; the Spectrum just beeps continuously when I try to run it. I suspect the URL may have died, and I have spares, but I'm hesitant to replace it in case the same happens again. Might there be an underlying fault with another component?
4S - wavy grey lines, no boot
4S - wavy grey lines, no boot
Hi,
I have a 4S which I successfully repaired by changing the CPU (not the same 4S as in my previous topic). I tried loading Bubble Dizzy from my Sony cassette deck, but partway through loading, the Spectrum returned to the copyright screen. I powered off, plugged in a Retroleum X-ROM card, and ran some tests. All RAM and the internal ROM are working. Partway through the lower RAM refresh test, the display changed to some wavy grey lines, and this is now all that I can get from this machine. The X-ROM will now not run; the Spectrum just beeps continuously when I try to run it. I suspect the URL may have died, and I have spares, but I'm hesitant to replace it in case the same happens again. Might there be an underlying fault with another component?
I have a 4S which I successfully repaired by changing the CPU (not the same 4S as in my previous topic). I tried loading Bubble Dizzy from my Sony cassette deck, but partway through loading, the Spectrum returned to the copyright screen. I powered off, plugged in a Retroleum X-ROM card, and ran some tests. All RAM and the internal ROM are working. Partway through the lower RAM refresh test, the display changed to some wavy grey lines, and this is now all that I can get from this machine. The X-ROM will now not run; the Spectrum just beeps continuously when I try to run it. I suspect the URL may have died, and I have spares, but I'm hesitant to replace it in case the same happens again. Might there be an underlying fault with another component?
Re: 4S - wavy grey lines, no boot
It was the ULA. The ULA was from another machine that had 6 faulty RAM ICs, so it's not surprising that it died. Time to look out for a cheap ULA...