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SiriusHardware · 28th Mar 2020, 8:11 pm

You are quite fortunate that such an early machine (presumably with an early ULA) works OK with the LCD display after conversion to composite. In theory it should have the same 'dark screen' problem as ZX81 #2 which you gave away.

That location of yours seems to be some kind of Bermuda Triangle for cassette mechanisms (loading problems on PET, Spectrum and ZX81).

The first thing I am wondering is whether you are still trying to use a stereo lead, where the contacts on the ear / mic sockets on the ZX81 and Spectrum (which are the same) are designed / spaced for a mono plug. Are you now using a mono lead? If not, you are likely to have problems because the contact spacing on the sockets is such that one of them tends to short two sections together on a stereo plug.

When you say the machine freezes and you have to unplug, when exactly is that, you go load "", the screen goes blank and you don't see any squiggly lines when the program starts playing from tape? Can you break out of that state with 'Break'? If you can, the machine has not frozen or crashed, it is just failing to see any audio coming into the EAR socket for some reason.

28th Mar 2020, 8:11 pm	#211
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,559	Re: Zx81 You are quite fortunate that such an early machine (presumably with an early ULA) works OK with the LCD display after conversion to composite. In theory it should have the same 'dark screen' problem as ZX81 #2 which you gave away. That location of yours seems to be some kind of Bermuda Triangle for cassette mechanisms (loading problems on PET, Spectrum and ZX81). The first thing I am wondering is whether you are still trying to use a stereo lead, where the contacts on the ear / mic sockets on the ZX81 and Spectrum (which are the same) are designed / spaced for a mono plug. Are you now using a mono lead? If not, you are likely to have problems because the contact spacing on the sockets is such that one of them tends to short two sections together on a stereo plug. When you say the machine freezes and you have to unplug, when exactly is that, you go load "", the screen goes blank and you don't see any squiggly lines when the program starts playing from tape? Can you break out of that state with 'Break'? If you can, the machine has not frozen or crashed, it is just failing to see any audio coming into the EAR socket for some reason.