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ZX Spectrum power supplyHi, I'm looking for a small lightweight power supply that would be a perfect substitute for the original, it's meant for a video patched zx spectrum…
... a regulator to give approx. 8V for the Spectrum. This lower voltage ... -
ZX Spectrum power supplyHi, I'm looking for a small lightweight power supply that would be a perfect substitute for the original, it's meant for a video patched zx spectrum…
... a regulator to give approx. 8V for the Spectrum. This lower voltage ... -
128k +2 (grey) Ear mod - New ULA and still problemsBverstee kindly sold me a 128K ula since the one in my +2 seemed to have a broken ear in. But even with the new ULA, I still can not load games throu…
... /> I only need a 7805 regulator and a 9 volt battery ... , protected via a resistor or voltage divider and a zener diode ... -
WIP: ULAPlus hardware implementationThis aims to be an "almost" plug-in replacement for the Sinclair ULA chip fitted in Spectrum 16K/48K/Plus machines. It comes in a form of a small PC…
... another, for the non contended RAM. Also the board has been ... , thick components, such as the voltage regulators and the big capacitors ... -
Needing new capacitors. Where to buy online?Hi. I need new axial capacitors for a whole bunch of Speccy boards I have. Problem is, it's been hard to buy some of them online. Some shops will onl…
... can't find the exact voltage you can replace with the ... with one of higher voltage and got his RAM chips not working ... . He had to step the voltage rating ... -
12V -> 9VI found this simple dc-dc converter: [url]http://www.mcrent.com/workbench/dcdc1216/[/url] it converts 12V to 16V, can it be used to produce 9V by mod…
... what input voltage?
It's a step-up regulator, so ... -
Diagnosing a strange software fault in a 48kHi, A friend gave me a 48k, which I am very keen to restore. The spectrum 48k was my first computer over 20 years ago and I owe my ability to code t…
... ). You might replace the 7805 regulator too as it's known ... check is on 4116 RAM IC's in lower ... shows image (which needs lower RAM + video encoder to work), ... this). 3) Run more RAM software tests to determine if ... in place of the upper RAM.
Watch ... -
48k faultyHi guys! I have a 48k that, currently, presents 2 problems: 1 - Can?t sync to TV correctly. I get a lot of noise and the characters appear to be inc…
... electrolytic capacitors, and perhaps 7805 regulator too. When done, check supply ... and -5V) at the lower RAM.
Only when that ... -
Fixing a broken ZX Spectrum HELPHello I have no experience with computers predating the PC and this is my first computer of this sort S: One of my father's coworkers gave me his ol…
... smoke out of the 5v regulator. If you're lucky the ... the supply circuits and the ram won't have been fried ... -
Fixing a broken ZX Spectrum HELPHello I have no experience with computers predating the PC and this is my first computer of this sort S: One of my father's coworkers gave me his ol…
... smoke out of the 5v regulator. If you're lucky the ... the supply circuits and the ram won't have been fried ... -
My 48K Speccy has died.Hi fellow WoSer's! Wondering if you could help me with my rubber key 48k Spectrum, which died on me this afternoon. It is one I prevoiusly fixed up j…
... likely the lower 16K of RAM that has failed. Having said ... /> - Check the supply voltage to the lower RAM, make sure all voltages ... from radiated heat, but the RAM should not.
Removing ... you confirm it's bad RAM, remove all the chips, put ... -
Altera CPLD vs Xylinx FPGAI will dig into the world of FPGA's, mainly to find something that can replace one or more GALs for my current and new projects. And it's never bad t…
... to do something to shift voltage levels, so always make sure ... and lookup tables are all RAM-based. However, for larger designs ... amount of fast dual-ported RAM, and also the CLB look ... memory (Xilinx calles it "distributed RAM"). Many but not all FPGAs ... -
Faulty French +2 grayA friend of mine has a faulty french +2 grey model. The picture its giving out is this... [URL=http://imageshack.us/photo/my-images/19/post2036357600…
... ram. if not then one ore more of the components of voltage ... .
pending on the voltage loss - checking the schematics should ... to replace some of the RAM chips.
I would ... -
The new Superfo cloneHi In the spanish forum speccy.org some guys and me have optimized the superfo clon to have less ICs. The actual design has 39 ICs versus the 45 ICs…
... ) I think that's the ram pages for screen, anyway, those ... this is an issue of Voltage compatibility, It should appear on ... -
The new Superfo cloneHi In the spanish forum speccy.org some guys and me have optimized the superfo clon to have less ICs. The actual design has 39 ICs versus the 45 ICs…
... have nothing to do with voltage levels ;-)
... to access the video ram and the Z80 to ... access the upper ram without collision. But when ... doesn't need the video ram, the Z80 has unhindered ... is coupled to the video ram through resistors, in this ... -
Difference between brands of 4164 chips?I have gotten my hands on a batch of several brands of 4164 chips. Examples are NEC D4164C-3 and Mitsubishi M5K4164ANP-15. Anyone knows if any type …
... "find alternative for the RAM". Not that RAM or ROM will ever ... Speccy die or modify the voltage convertor to meet issue 4 ... -
Rocky Gush Floppy Drive InterfaceI have a Rocky Gush Floppy Drive Interface which I would like to post the details under the Hardware section of the website. What is correct procedur…
... data corruption. When the supply voltage is dropped with the LED ... =>not busy), and that RAM is at 0x3000 and ROM ... -
Spectrum 128K +2 problemhello, i am try to repair my spectrum 128k +2 grey, i remove all ram chips and i have some new ones spares, now i have remove all ram chips, i want …
... up/reset, before accessing any RAM. I would imagine the 128 ... all of them get some voltage? i have a multimeter.
Spectrum 128K +2 problemhello, i am try to repair my spectrum 128k +2 grey, i remove all ram chips and i have some new ones spares, now i have remove all ram chips, i want …
... up/reset, before accessing any RAM. I would imagine the 128 ... all of them get some voltage? i have a multimeter.
RAM or ROM chips).
< ... should also go to one RAM chip and each data ... ULA should go to one RAM chip (the data bus ...Setting up an IDE HDD on the +3e helpHello, Just installed a HDD in my +3e (ROM ver. 1.11). When turning on it takes a few seconds longer but then shows 2 IDE (available) as well as 1 fl…
... can operate happily on either voltage so long as it is ... the same as the logic voltage. i.e. You mustn't ... have an optional 3.3v regulator since parallel ATA uses TTL ...Repair 128k +2 grey part2hi all, i am trying to fix it couple of weeks now, i bought a working one for tests and parts check so until now, power TRs are all news memory IC'…
... RAM IC's
also very important is to check regulator ... 78S05 and TR8/TR9 (replace them)
critical RAM ... IC's 25-32 (contended RAM) if these IC's works ...another faulty zx spectrum +2 to fix!!!Hello to all, I'm new here... I have got a faulty +2 (gray) and start to try fix it... I have read the treads of xaris_sm and Pluto63 as background…
... very hot...
Two ram chip (IC28 and IC30) ... want remove the two ram chips... but with my ... replacement for the two dead ram...
thanks to all ... because it puts out a voltage out of specification. TTL ... and then change the hot RAM chips, WITHOUT TRYING TO ...48k + Spectrum Issue 4S Display IssueHi all! Brand new user here. Growing up I had a zx spectrum for a little bit, and recently I have bought a working 48k + Spectrum (Issue 4). I was…
... a replacement. Its a 5V regulator correct?[/QUOTE]
Wait ... BEFORE changing electrolytics and removing RAM chips, and 2.5V After ...48k + Spectrum Issue 4S Display IssueHi all! Brand new user here. Growing up I had a zx spectrum for a little bit, and recently I have bought a working 48k + Spectrum (Issue 4). I was…
... use capacitors with a lower voltage rating than the originals, then ... may not with the lower RAM removed)?
I can ...Power led for the Spectrum+?Hi, is there a way to make a power led for the Zx Spectrum+? I'm looking a safe way to connect the 2 wires to board. Becase i'm new to the spectrum h…
... the external PSU (before the regulator) or on the 5V rail ... normally 20mA and the typical voltage normally ranges from 1.4V ... .
For example the voltage of the LED is 1 ... rail, then first measure the voltage so that your resistor calculations ...another faulty zx spectrum +2 to fix!!!Hello to all, I'm new here... I have got a faulty +2 (gray) and start to try fix it... I have read the treads of xaris_sm and Pluto63 as background…
... while rising the input voltage if the voltage at the output is ... as ULA, CPU, ROM and RAM.
Maybe it is ...Is This PSU Useable on the Speccy?I just got my Speccy and the PSU has had some 'work' done to it. Somebody has added an extra length of cable on it but rather than soldering or crim…
... ) and that is a lower voltage than from the original in ... of heat generated by the regulator inside the Spectrum is reduced ...Is This PSU Useable on the Speccy?I just got my Speccy and the PSU has had some 'work' done to it. Somebody has added an extra length of cable on it but rather than soldering or crim…
... regulated DC input (actual measured voltage). For a unregulated input ... with a slightly greater input voltage.
However, the higher ... input voltage, the higher the heat level from the regulator (and ... have a multimeter, test the voltage. Test off load (not ...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…
... net/LRR"]ZX Spectrum lower RAM replacement module[/URL]. [ ... other faults, but overheating RAM ICs clearly suggests a ... voltages at the lower RAM's PCB pads - ... that I made. The RAM replacement module only uses ... 'll still want the voltage converter to be working ...
