Bricked spectrum zx 128k and 48k

Soldato
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Ok this was many years ago and 2 of these computers i had got bricked by pulling out the joystick interface while they were powered on.
After that they showed a noise screen when turned on like you got on old crt tv when it got no signal.

I can't remember this proper since its well over 25 years ago but i got thinking about it and wanted to know what happened to the units and would they have been fixable? Both were binned.
 
Caporegime
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Probably binned, I used to work for Dixons when the Spectrum+ was a thing and we had countless returns of them, they were sent back to the distribution centre in a cage marked “waste” - along with other items not worth repairing, higher value items such as Video cameras etc went in a different cage and were directed to a repair facility rather than back to the D.C.
 
Soldato
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dang, not sure but this issue must have been common if people mistakenly pulled out the joystick interface card thingy while it was powered on. i cant seem to find info on it though. very curious to know if it was fixable.
 
Caporegime
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Yes , unplugging peripherals whilst powered on was a killler of early home micros, I’m guessing they were very sensitive to any voltage spikes caused by such an activity, I bricked a couple of Spectrums by accidentally unplugging sticks etc whilst demonstrating them :o

The Acorn BBC didn’t have such fragility, perhaps because it was designed with school use in mind? - you could plug in or unplug anything and whilst it would cause the machine to hang it would power up again without issue.

I recall the Amiga 500 - which admittedly was a later design - was immune from the same thing, the TV modulator would fall off if you so much as looked at it with no ill effects once it was plugged back in, same if you yanked the mouse lead out etc

Almost certainly repairable I’d say although wether it was economically viable to do so is probably doubtful hence so many old 8 bit machines getting skipped.
 

GeX

GeX

Soldato
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It can cause all sorts of faults;

"First, the reason for at least 80-90% of faults on these computers. The primary cause, is plugging or unplugging any interface onto the computer while it is switched on. Interfaces, are any add on unit that plugs into the expansion slot, found at the rear of the machine. The largest of which is the joystick interface. In a lot of cases, the customer does switch off before plugging or unplugging the interface. The reason a fault then occurs, it that the Keyway Locating Peg that is fitted on the interface plug, drops out, this allows lateral movement of the interface. This in turn allows the Spectrum O/P's to be shorted together. Considering that most of the IC's are hung on this O/P port, a multitude of faults can occur. Some of which can be uneconomical to repair. fig 4 - 8."

https://k1.spdns.de/Vintage/Sinclai... 48k repair guide (ian worsley)/rep_spec.html
 
Soldato
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Was the Spectrum 128k +2 less susceptible to this problem of bricking?

Reading all this, I'm quite shocked I didn't blow up my Speccy back in the day!
 
Soldato
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I did the same on my 48K+

it turned out there’s a see through fuse in them which blows when you do this. Replacing that fixed it for me.


M.
 
Soldato
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wish i had know about this fuse back then.

Yeah I learned about it and I think I fixed it (I can't remember exactly what happened but the joystick adapter got pulled out which fused it - hence why the later editions had a little clip that went around the power supply cable so if you pulled out the adapter it killed the power) but then the 48K+ got stolen and I moved to a C64.

Do miss my old computers.



M.
 
Soldato
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I've recently bought an Issue 3 rubber key Spectrum off Ebay that's been refurbed with a composite video mod, new membrane, and new power regulator (though the case isn't perfect), and in my research while getting one, I found that Spectrums are surprisingly fixable these days.

Parts are readily available, including modern replacements for the ULA chip which was prone to overheating and failure. You can even buy funky coloured cases, faceplates and keymats. It's relatively straightforward to diagnose problems as they're a very simple design by modern standards (any hobbyist who is halfway competent with a soldering iron can replace any of the parts, unlike modern tiny surface mounted components), and most of the faults and their solutions are known.

As they are rarer now it's probably worth fixing them up more too.

I've certainly enjoyed going back nearly 40 years to my teens and re-experiencing the old games on the original ZX hardware (but with instant, 100% reliable loading from SD card). It's a real trip down memory lane.
Next, it's time to get my ZX81 back up and running, and refurbed. I love that computer - my entire career started on the ZX81, but the one I have now is a faily tatty replacement as I sold my original (mint conditon one, with Memopak 16k) for £25 to help pay for a C64, back in 1984/5 :(.
 
Associate
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I must have been lucky with my 48k speccy as I'm sure the joystick got yanked out many a time and last time I checked it still fired up. Used to have some heated sessions on two players gauntlet with one person on keys and and other on joystick.

I am however missing a coupe of keys off the keyboard that have been lost in the mists of time!
 
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