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zx.zigg.net lower RAM replacement module: Still shipping?Hi everyone I'm trying to resuscitate my 48k issue 6a, and I bought the lower RAM replacement module from zx.zigg.net. The paypal payment went thr…
... 6a, and I bought the lower RAM replacement module from zx.zigg.net ... -
16K/48K Lower RAM (4116) replacement.You may want to read [URL="http://www.worldofspectrum.org/forums/showthread.php?t=37957"]this thread[/URL] for background information on the quest t…
... found an SRAM based replacement for the lower RAM that works in ... the column address to the RAM and so there isn' ... levels that appear on the lower RAM address lines. In particular, ... this is the ZX Spectrum Lower RAM Replacement Module, pictured below:
< ... -
ZX Spectrum upper RAM module (4532/4164 replacement)Following the [URL="http://zx.zigg.net/LRR/"]lower RAM replacement module[/URL], there have been quite a lot of requests for something similar for th…
... ="http://zx.zigg.net/LRR/"]lower RAM replacement module[/URL], there have been ... ="http://zx.zigg.net/LRR/"]lower RAM replacement module page[/URL] and place ... same circuit as the lower RAM replacement and emulates dynamic RAM.
Here ... -
Replacing lower RAM 4116 ZX Spectrum 48k - desoldering advice please?A long post, but interesting pictures perhaps. :) I'd like some advice: (also apologies I think I picked the wrong 'Hardware' category for this, plea…
... online seemed to indicate a lower RAM issue. It hadn't been ... chips, nine 16-dip sockets, replacement keyboard membrane. My plan is ... solder was applied to the lower side and it had travelled ... -
ISR's in lower ram, a.k.a. the snow effect - did any game or demo ever use this?Hi all I've been curious to see what the 'snow effect' looked like in real life for a while now so today I wrote a quick IM 2 ISR in lower ram to wi…
... quick IM 2 ISR in lower ram to witness it firsthand. Pretty ... -
Upper RAM replacement module issues with the DivideI got my new upper ram replacement module from Zorn yesterday and seem to be having some issues. When the machine is without the Divide it boots up …
... got my new upper ram replacement module from Zorn yesterday ... manages to boot, the ram passes the memory test ... When I put the upper ram chips back in place, ... />
The upper ram are not on the "OKI ... upper RAM and uses unusual timings that the replacement can ... -
12V ripple with lower ram installedI repaired a speccy this week. Before doing anything I replaced all caps and measured the transistors in the power section. When doing this I found t…
... Then removed and socketed all lower ram. turned the speccy back ... the scope. Inserted a lower ram module and the speccy was ... Then removed the lower ram module and reinserted all original lower ram ic's ... wasn't there when the lower ram module was inserted.
... -
help with my original issue 3b from when i was a teen. possible lower ram fault.hello, well ive tried to fix my old speccy, but haven't made much progress. could you help me out with some diagnosis. the fault occurred about…
... /> is this more likely a lower memory fault? or is my ... certain before I order a lower ram set. -
The Complete List Of The Causes Of Lower Ram Failure?Well the aim is to get a comprehensive list.I ask this because I know very little about it . I know that failure of "power supply" related capacitors…
Well the aim is to get a comprehensive list.I ask this because I know very little about it . I know that failure of "power supply" related capacitors can do this . But I suspect there are loads of other ways to damage lower RAM ICs? Any ideas? -
zx spectrum display corruption .. with lower ram module installed[img]https://photos.app.goo.gl/Gu6rjC5v21sZxwTX9[/img] [img]https://photos.app.goo.gl/FznVw8SkbbhWn5mh7[/img] another specie question : i have …
... with video corruption, it has lower ram module fitted.. can get it ... and it shows lower ram as good and upper ram not detected although ... start digging at the upper ram, or the 4 logic chips ... that drive the upper ram.. i am presuming that one ... -
Double keystrokes on zx spectrumHappy New Year everyone. I have this spectrum 48k issue 3b I?ve been working on now and then. I have replaced upper rams, installed a lower ram repla…
... replaced upper rams, installed a lower ram replacement module and it starts up ... -
Testing 4116 type DRAMsHappy New year All! I'm managed to find some time to repair some more Spectrums :) woo hoo. I have a couple with busted lower RAM, Sooo, I appr…
... have a couple with busted lower RAM, Sooo, I appreciate I could ... buy a swanky ZX Spectrum Lower RAM Replacement Module, but I think that ... feasible to actually make a ram module replacement with ease? -
ZX Spectrum 48k Issue 2 Faulty Ram?Hi, I have a faulty ZX Spectrum Issue 2 motherboard. Looks in very tidy condition. Though I'm getting random columns of blocks and flashing cursors…
... .zigg.net/LRR"]ZX Spectrum lower RAM replacement module[/URL]. [URL="http ... other faults, but overheating RAM ICs clearly suggests a problem ... by measuring voltages at the lower RAM's PCB pads - look ... ] that I made. The RAM replacement module only uses the main ... -
ZX Spectrum 48k Issue 2 Faulty Ram?Hi, I have a faulty ZX Spectrum Issue 2 motherboard. Looks in very tidy condition. Though I'm getting random columns of blocks and flashing cursors…
... /> Some advice on the replacement of the power RAM. It does not ... 4116 chips or use the lower RAM replacement module, you still have to ... -
ZX Spectrum 48k Issue 2 Faulty Ram?Hi, I have a faulty ZX Spectrum Issue 2 motherboard. Looks in very tidy condition. Though I'm getting random columns of blocks and flashing cursors…
... /> Some advice on the replacement of the power RAM. It does not ... 4116 chips or use the lower RAM replacement module, you still have to ... electrolytic caps, is there better replacement available? Or can I pick ... -
Poorly Issue One 16k spectrum diagnosis?Hello, everyone. :smile: I was lucky enough to buy an Issue One 16k rubber key the other week; I didn't know it was an Issue One till I opened it up…
... chips for Zorn's excellent lower ram replacement module. I get a different ... pins of the far right RAM chip with a bit of ... -
Poorly Issue One 16k spectrum diagnosis?Hello, everyone. :smile: I was lucky enough to buy an Issue One 16k rubber key the other week; I didn't know it was an Issue One till I opened it up…
... . I am assuming that the lower RAM replacement module is OK.
RAM and ROM removed you get ... pure white. With only the RAM removed you get a black ... -
Poorly Issue One 16k spectrum diagnosis?Hello, everyone. :smile: I was lucky enough to buy an Issue One 16k rubber key the other week; I didn't know it was an Issue One till I opened it up…
... of it while developing the lower RAM replacement module. Are you using one ... -
Poorly Issue One 16k spectrum diagnosis?Hello, everyone. :smile: I was lucky enough to buy an Issue One 16k rubber key the other week; I didn't know it was an Issue One till I opened it up…
... of it while developing the lower RAM replacement module. Are you using one ... -
ZX Spectrum upper RAM module (4532/4164 replacement)Following the [URL="http://zx.zigg.net/LRR/"]lower RAM replacement module[/URL], there have been quite a lot of requests for something similar for th…
... ="http://zx.zigg.net/LRR/"]lower RAM replacement module[/URL], there have been ... similar for the upper 32K RAM in a Spectrum.[/QUOTE]
replacement modules are in, compared to ... -
Poorly Issue One 16k spectrum diagnosis?Hello, everyone. :smile: I was lucky enough to buy an Issue One 16k rubber key the other week; I didn't know it was an Issue One till I opened it up…
... :
1. (With 4116 RAM installed): Speccy sends a low ... symptom (2.) appears when the lower RAM replacement module is being supplied with ... effect of making the 4116 RAM only just readable.
Fixing my old ZX Spectrum 48K issue 4AHi Guys, I trying to fix my old Spectrum 48K. Looks like my dad used a wrong power supply as the ULA had a bit missing and so did the 7805. So I rep…
... on screen, the rest of lower RAM might be OK.
lower RAM replacement module from here: [URL]http ...ZX Spectrum 48K AV IssueOK so I dugout my old 48K Speccy today and decided to AV mod it. I did the mod (pretty easy) but the picture I am getting is this. [url=http://posti…
... start off by replacing TR4 (replacement would be either a ZTX651 ... this point.
4116 RAM can be sourced on eBay ... Zorn on here sells a lower RAM replacement module.
BZX Spectrum 48K Issue 3, loss of -5V rail.Hi all, I've googled this problem and poured over the electrical diagrams for the circuitry concerning the power supplies and I believe I know what …
... matter if you use the lower RAM replacement module, but it'd still ...'Interesting' Issue 2 modSo I've been lurking on this forum for a while and I've got to the point where I want to see if I can repair a speccy.. so I bought me a 'broken' one…
... /> [*]Fit one of Zorn's lower RAM replacement modules
[/LIST]
With ...48K Ram Check Command not workingI am trying to repair my Spectrum 48k. It is having issues loading games, sometimes they load all the way to launch and then the speccy resets. Oth…
I'd just swap them all out if it was me. Put sockets in and fit nice new ram modules or use Zorn's lower RAM replacement module.The Spectrum Resuscitation ThreadKicking off this thread as a place where people who are fixing/restoring Spectrums (or indeed any other piece of related hardware) can show off their…
... ="http://zx.zigg.net/LRR/"]Lower Ram Replacement[/URL] (LRR) module from zx ... aspect of the Spectrum (4116 lower RAM) and result in a power ...The Spectrum Resuscitation ThreadKicking off this thread as a place where people who are fixing/restoring Spectrums (or indeed any other piece of related hardware) can show off their…
... ="http://zx.zigg.net/LRR/"]Lower Ram Replacement[/URL] (LRR) module from zx ... aspect of the Spectrum (4116 lower RAM) and result in a power ... having a look at a replacement for the 7805 in the ...Faulty 48+ Help NeededHi, This is what I get when I plug in the spectrum, this is tuned in. Vid shows a reset. Any ideas, or pointers on the first thing to check. Keyboa…
... the thought of Zorn's lower ram replacement got ever more appealing, these ... off the rest of the lower ram IC's, their legs are ... thinking that to buy the lower ram replacement module is the next step ...Faulty 48+ Help NeededHi, This is what I get when I plug in the spectrum, this is tuned in. Vid shows a reset. Any ideas, or pointers on the first thing to check. Keyboa…
... I could identify a bodged replacement of IC6 I was curious ... was going on underneath every lower ram IC, I uncovered nothing, but ... 'll probably go for the lower ram replacement module or buy a few ... mean the TR4 and TR5 replacement was a success also?
