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Fixing a poorly Issue 3 - Odd faults.Here's one for you Spectrum fixers, I warn you it's a long one. I've spent a couple hours this evening doing several repairs on a rubber keyed Speccy…
... and the machine passed lower and upper ram tests. Switched on without ... have a spare one those lower ram modules, I may replace all ... the ram with it and give that ... -
Fixing a poorly Issue 3 - Odd faults.Here's one for you Spectrum fixers, I warn you it's a long one. I've spent a couple hours this evening doing several repairs on a rubber keyed Speccy…
... removed all the old lower ram ic's and fitted ... shorts. Fitted a spare lower ram module and was greeted ... graphics garbage with no ram present. I also checked ... continuity between the ram module pins, and solder ... have to buy more lower ram ic's, or another ... -
Fixing a poorly Issue 3 - Odd faults.Here's one for you Spectrum fixers, I warn you it's a long one. I've spent a couple hours this evening doing several repairs on a rubber keyed Speccy…
... leading to one of the lower ram ic's. I've tacked ... a wire on between the lower ram and a resistor where the ... track was, a replacement ram ic had been fitted earlier ... ho and removed all the ram ic's which to ... was caused from the previous ram repair. So I've ... -
help with issue 3 48k speccy after recap and new tr4 and tr5I have a 48K speccy that was not working. After recapping and replacing TR4 and TR5 it came back to life However after a short while running weird …
I'd suspect the lower RAM chips first - obviously check ... corrupted - indicative of faulty RAM, and I'd say an ... messed up by a faulty RAM chip or two. Not ... you can still get a lower RAM board, but that may ... good way forward if indeed lower RAM is to blame, those ... -
Bit of fun - one change onlyI also posted this on another marque's forum (for their products) to see. Its just a bit of fun really. OK, if you could of made one change to a S…
...
Remapping memory, be it RAM or ROM is relatively simple ... ULA controls the ROM and lower RAM area, but 74 series ... control the upper 32k of RAM. The board design is ... out the ROM and put RAM in it’s place, ... ZX Spectrum with 80k of RAM and a built in ... -
48K Issue 2 RAM issuesI have 48K issue 2 board (I've checked, the upper memory is present!). It's not very well. I've not attempted to diagnose one before, so please bear …
... value on screen. If the RAM was working correctly, you should ... /> If BASIC works, then the lower RAM is fine.
The ... tests from the highest possible RAM address down to the lowest ... possible RAM address.
[b][i ... -
Another Spectrum is brought back to life.Hi Spec-chums. I have been having bit of busy afternoon with repairs today. I've brought back to life a Panasonic Super-VHS recorder, and more intere…
... it could still be a RAM fault.
If you ... , but that there is a lower RAM fault.
Note that ... -
ZX Spectrum rescued from a friend, has Issues.Hi guys, I've recovered this ZX spectrum 48K from a friend. It's a 1984 ISSUE 6A. He told me the last time it was turned on was about 30 years ago!.…
... and hence NOT accessing the ‘lower’ RAM, the value on the data ... -
ZX Spectrum rescued from a friend, has Issues.Hi guys, I've recovered this ZX spectrum 48K from a friend. It's a 1984 ISSUE 6A. He told me the last time it was turned on was about 30 years ago!.…
... and hence NOT accessing the ‘lower’ RAM, the value on the data ... -
More on the Cheetah RampackI should be more careful about doing "repeats" ( I should learn some manners) but I could not find anything recent on these . But here is on WOS …
... could read enough to see "Lower RAM error at 57FFB " And "32K ... Upper Ram OK" ( I think this means ... is OK) .Then it said "Lower Ram error encountered ". Two of the ... ,IC4 were listed in the lower middle right of screen.
The Different Approaches To Upgrading the ZX Spectrum from 16K to 48K This is probably something that has been covered before . I will take a look to see if I can find anything on WOS
... is also interesting that RAM pack wobble and other ... a common cause of lower RAM failure , I got ... job in showing up lower RAM failure though I cannot ... wobble from the Cheetah RAM pack I got with ... upfront initial RAM upgrade risk 2) ongoing Ram pack wobble ...The Different Approaches To Upgrading the ZX Spectrum from 16K to 48K This is probably something that has been covered before . I will take a look to see if I can find anything on WOS
... ve already brought an upper ram module from Retroleum. The 74LS ... that I repaired with a lower ram module. Only thing I will ... your replacing previously fitted faulty ram, then you have to do ... benefit with a lower current draw with the ram modules though. Other ...The Different Approaches To Upgrading the ZX Spectrum from 16K to 48K This is probably something that has been covered before . I will take a look to see if I can find anything on WOS
... had figured out that replacing lower RAM would be tricky with a ... . So the Ram modlues can replace lower and upper RAM leaving lower RAM in place ...The Different Approaches To Upgrading the ZX Spectrum from 16K to 48K This is probably something that has been covered before . I will take a look to see if I can find anything on WOS
... /offer/details/ZX-Spectrum-4116-(lower-RAM)-replacement-module.-2741"]https://sellmyretro ... .php?67363-An-alternative-Spectrum-lower-RAM-replacement"]amibay.com/showthread.php ... ?67363-An-alternative-Spectrum-lower-RAM-replacement[/url]
The Different Approaches To Upgrading the ZX Spectrum from 16K to 48K This is probably something that has been covered before . I will take a look to see if I can find anything on WOS
... excellent Joules per Colomb covers lower RAM replacement in this You Tube ...The Different Approaches To Upgrading the ZX Spectrum from 16K to 48K This is probably something that has been covered before . I will take a look to see if I can find anything on WOS
... 32K bytes of RAM.
For the ‘lower’ 16k bytes ... of RAM, there are the following ... chips.
[*]Use a lower RAM replacement module (there are two ... br /> [*]Make your own lower RAM replacement equivalent to a LRR ...48K ZX Spectrum 48K Recap (Capacitors) Or Not?I have seen arguments "for an against" on this subject by some "high calibre" experts . So if the experts can differ on this question then my questi…
... 2 between the upper and lower ram. It gave symptoms of a ...48K ZX Spectrum 48K Recap (Capacitors) Or Not?I have seen arguments "for an against" on this subject by some "high calibre" experts . So if the experts can differ on this question then my questi…
... 2 between the upper and lower ram. It gave symptoms of a ...48K ZX Spectrum 48K Recap (Capacitors) Or Not?I have seen arguments "for an against" on this subject by some "high calibre" experts . So if the experts can differ on this question then my questi…
... are only "slightly damaged" (say lower Ram failture) so this is where ...How can I fix a problematic Retroleum Smart Card. I did not do anything "WRONG " with it but I did but it on a flexible cable and this seems to have "upset" it .Since then It does not perform the …
... this . It said lower RAM was OK . Upper Ram failure at $FFFE .Then ... colour palette test confirms upper RAM error encountered . Suspect IC21. IC ...How can I fix a problematic Retroleum Smart Card. I did not do anything "WRONG " with it but I did but it on a flexible cable and this seems to have "upset" it .Since then It does not perform the …
... 2 that had no Upper Ram at all . I connected up ... top of screen it said "Lower RAM error ar S7FF0 (the last ... said "No upper RAM detected"
The lower part of the ...Not bored with the Boards.Going through some old tapes stored rather badly I came across an unlikely item that that I must have stored away quickly with other low grade items …
... says now
Uper Ram "Value is Unstable"
< ... this result :-
Lower RAM error at $7FFF
Bad ... proceed further both upper and lower ram is bad .
... So I wonder why the lower RAM has suddenly "gone bad". Maybe ...Not bored with the Boards.Going through some old tapes stored rather badly I came across an unlikely item that that I must have stored away quickly with other low grade items …
... surprised this maybe caused the lower ram error but maybe soldering the ...The Diagnostic PCBIt arrived in the post today so this is my first go with the Diagnostic PCB. (bought on Ebay) This item , I think , does the same job as Retroleu…
... /> Then it states "upper and lower Ram OK"
ROM CRS ...Not bored with the Boards.Going through some old tapes stored rather badly I came across an unlikely item that that I must have stored away quickly with other low grade items …
... across an Issue 2 (lower Ram only) and managed to ... IC4
And lower RAM ERROR at $7FFB.
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Not bored with the Boards.Going through some old tapes stored rather badly I came across an unlikely item that that I must have stored away quickly with other low grade items …
... across an Issue 2 (lower Ram only) and managed to ... IC4
And lower RAM ERROR at $7FFB.
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Not bored with the Boards.Going through some old tapes stored rather badly I came across an unlikely item that that I must have stored away quickly with other low grade items …
... . This time ,the lower Rom tested OK so basically ... started , as the lower RAM failure shown with the ... speak with just the upper Ram problem.
RAM and suspect ICs in the lower RAM at ... So something had caused lower RAM failure this time What ...12V missing on an issue 3I’ve been working on an issue 3 Spectrum +. It shows thin distorted vertical stripes on bootup. +5 and -5V are all right but the 12V line measures ro…
... Card menu. I tested the lower ram in a known working motherboard ...If Sinclair computers had not been sold...I was just having a random thought. If Sinclair Computers (or the rights to them, not sure how it 'worked' back then) had not been sold to Amstrad…
... the Z80 to refresh the “lower” RAM (the 4116 DRAM chips) is ... write to this area of RAM, it is only freshed by ... documentation being wrong about the RAM banks used on the 128K ...
