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I Just Listed some games on eBay[URL="http://shop.ebay.co.uk/shineyflower/m.html?_nkw=&_armrs=1&_from=&_ipg=&_trksid=p4340"]I've just listed some games on eBay, and a couple of Larg…
... .. thats how I knew the lower ram on 1 machine was knackered ... -
Speccy repairs?I've finally got round to testing all the various Spectrums that I seem to have accumulated over the years and discovered that "my" two machines (i.e…
... or lower RAM is bad, most of the time it's lower RAM that ... />
Again, most likely bad RAM.
[quote]
[*] ... .
With suspect bad lower RAM you also need to check ... , then it actually kills the lower memory chips, the TMS4116 data ... -
Spectrum lost upper memoryHi again, I have a Rubber key Spectrum(issue 4S) which lost it's whole upper memory. It's worked okay, but i forgot it on over last night. My son wa…
... />
the heat on the lower ram is how a friend said ... -
The Sadness of my Decaying Speccies.I've been avidly collecting ZX Spectrums since the late 90's and whilst at the time of the late 90's and early millennium my Spectrums and associated…
9 times out of 10, RAM problems are with lower RAM (the 4116 chips ... more fragile than the upper RAM. Usually it's just one ... edge connector to test the RAM and tell which chip is ... bad.
4116 RAM was pretty much obsolete in ... -
The Sadness of my Decaying Speccies.I've been avidly collecting ZX Spectrums since the late 90's and whilst at the time of the late 90's and early millennium my Spectrums and associated…
... times out of 10, RAM problems are with lower RAM (the 4116 chips ... more fragile than the upper RAM. Usually it's just one ... edge connector to test the RAM and tell which chip is ... bad.
4116 RAM was pretty much obsolete in ... -
The Sadness of my Decaying Speccies.I've been avidly collecting ZX Spectrums since the late 90's and whilst at the time of the late 90's and early millennium my Spectrums and associated…
... saying, to be problems with lower RAM.
To amplify why ... the edge connector, thus killing lower RAM and usually the switch mode ... -
Maybe a bargain ?Hi guys, just won this on Ebay, Fingers crossed it all works ok, I may have got a bargain, what do you think ? [url]http://cgi.ebay.co.uk/ws/eBayISA…
the problem with speccy's is well people don't test em / sold as seen..
main 2 issues that could be a problem is bad membrane or lower ram prob.. hopefully neither and both are fixable. -
Help with broken SpectrumHi There, Just received a ZX Spectrum computer. It's an issue 3B (48k version). When I power it up (9V centre pin -V) nothing happens. It's complete…
... do that is on the lower RAM chips (lower left corner of board ... left) = -5V
Pin 8 (lower left) = +12V
And ... to remove the upper 32K (RAM chips in middle of board ... -
zx spectrum +2 troubleshootingHi There I am new here and I need some advise as to where to look for issues on my zx spectrum +2 it was working fine this morning .. then while pl…
... map you have contains a lower RAM region (16K) which belongs to ... contended bank, and an upper RAM region (32K) which belongs to ... />
If the non-contended RAM is damaged, the machine can ... .
If the contended RAM is damaged, the computer hangs ... -
Do ULAs die?Thought I'd start this thread as people often think their ULA is dead, when it's actually the RAM or power circuits. Searching the forum in the futur…
Anybody here an ebay sniper?Been bidding on [URL="http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=220692283001&ssPageName=STRK:MEDWX:IT#ht_500wt_1156"]this[/URL] and would …
... 'll find out if the lower ram is ***ed when I plug ... if the first bit of lower ram is broke (it replaces it ...ZX48K: KILLING keyboard membrane?Hi. My friend - JAD - decided to get back from C64 to ZX Spectrum 48K after some break (that's the man who coded this program [url]http://www.pouet…
1. Likely, lower RAM and/or the internal switch ... data sheet for the 4116 RAM and test the voltages to ...I wonder how many still goingThere is always a healthy stock of 48k rubber keyed speccys on eBay. However whats the guess on the amount world wide that are still working/used? +…
... all showing symptoms of bad lower RAM - well, except the one that ...So frustratingI'd recently socketed the lower 16k only to find the upper 32k also had issues. While removing 4 of the chips I've managed to break two tracks. The c…
if you've ripped up tracks you can certainly replace them with thin insulated single strand wire. I tore up an address line doing exactly the same as you, removing the remains of the pins of a couple of dead lower ram chips.Powering up a Speccy after long-term storage.Staying at my folks for Christmas. Feels good to be back in God's country again, even if it is -12C outside at the moment. :-o Anyway, I was plannin…
... could damage the, yet fragile, lower RAM chips.
Therefore, it ... : your computer could be damaging RAM chips as time happens, if ... (if not already) to the lower RAM chips.
- Try to be ... lucky again: one or some lower RAM chips are gone.broken 48K, strange screenwell I finally socketed all lower 16K ram chips, (8 of them in a row near corner, not those 4 in two rows) and replaced them with new ones but it did…
... works, supply voltages restored & lower RAM replaced, there isn't much ...broken 48K, strange screenwell I finally socketed all lower 16K ram chips, (8 of them in a row near corner, not those 4 in two rows) and replaced them with new ones but it did…
Lower RAM is quite(!) different from upper RAM.Testing memory/transistors etc with multimeterAnyone have a rough guide to show how to do this properly? Im using the diode setting on the multimeter to test various components, im touching the b…
... em but unless it's lower ram or ula I've not ...Testing memory/transistors etc with multimeterAnyone have a rough guide to show how to do this properly? Im using the diode setting on the multimeter to test various components, im touching the b…
... boards that ive tested the lower ram at least seems sound, went ...repaired a 48K, yay :)I just managed to repair one 48K. After socketing all eight lower RAM chips (hard work!) and replacing few of them, it showed the familiar "Sinclair …
[QUOTE=orange;504687]question: does that mean all lower RAM is now OK? (if so, I could use it to test chips)[/quote]
Yes. Each chip is in charge of one bit of data.Speccy 128 Shadow screen.How much is the shadow screen used in 128k commercial software? I ask because I am looking at putting 128k of memory in the 48k setup I have been bu…
... seperate ram for the ULA ram and the non-ULA ram, ... reading the non-ULA ram (So i dont care ... two pages the ULA ram is presenting), which means ... is the Refresh of the lower ram, which i will probably ... currently using with a static ram chip instead.
How the spectrum generates the video from ramHi everyon, I know that most people here allready know this but i think i found out how the spectrum acctually dispalys stuff and why the LD x, (HL)…
... the ULA reads the video ram in a real spectrum by ... or writing to the lower 16k of ram in a real spectrum ... is the master of the lower ram and even takes care of ...How the spectrum generates the video from ramHi everyon, I know that most people here allready know this but i think i found out how the spectrum acctually dispalys stuff and why the LD x, (HL)…
... the ULA reads the video ram in a real spectrum by ... some other area than the lower 16K, there is no conflict ... is the master of the lower ram and even takes care of ...Was the +3 a missed opportunity?I just wanted to gauge WOS opinion on this. Do people think that the +3 was a bit of disappointment that didn't really advance the hardware as much a…
... /12v supply fails and the lower ram burns out! :smile:[/QUOTE]
lower ram failiure in my speccy 48 ...Fully integrated ZX+Hi, I just want to show some inspiration for integration HW to ZX+ case ;-) - ZX48 issue 3 board, without all parts regarding video generating (pa…
... tell the difference between a lower Ram read by the CPU (Always ... page 5) and a lower ram read by the ULA (Page ... 7 depending on the shadow ram pin), so i havent been ...Some 48k+ packages for saleSoon! Rwap is sending over a few membranes for 48k+ machines, so far, got two fully functional (and looking good!), soon as the membranes are in the…
... an interface 2 to detect lower ram probs.. if horace on cart ...2 48K speccys dead..Hey guys! I've got two of our rubbery friends with me that need some help. They've been like this for some time, but I would like to try and fix th…
... /> Indeed check voltages on the lower RAM chips - the above looks OK ... keyclick, ULA (most likely) or RAM / ROM / Z80 fault.
2 48K speccys dead..Hey guys! I've got two of our rubbery friends with me that need some help. They've been like this for some time, but I would like to try and fix th…
... ]Indeed check voltages on the lower RAM chips - the above looks OK ... keyclick, ULA (most likely) or RAM / ROM / Z80 fault.[/QUOTE]
2 48K speccys dead..Hey guys! I've got two of our rubbery friends with me that need some help. They've been like this for some time, but I would like to try and fix th…
... and replaced 7805. On the lower RAM I'm getting -5V/+10V ...Hi everybody! Need help trying to rescue a ZX 48K...Hi, since this is my first post, a bit of info about me: I'm an Italian guy, now living in Poland (Warsaw), informatics and electronic geek since…
... hot.
The lower 16K RAM is more exposed to failure ... chance that some of the lower RAM is defective.
Check if ... any of the RAM-chips are hotter than the ... just have to replace the RAM and see if it helps ...
