-
How the DC-DC converter worksI've not seen this before. The DCC-DC converter inside the Speccy has always been quite a mistery for me: [url]http://www.tablix.org/~avian/blog/arch…
I've not seen this before. The DCC-DC converter inside the Speccy has always been quite a mistery for me:
[url]http://www.tablix.org/~avian/blog/archives/2006/05/spectrum_dc_to_dc_converter/[/url]
Apologies if it's a double posting. :) -
R-785.0-1.0 5v 1A DC-DC converter Group Order.As discussed in the other thread there seems to be interest in getting a consignment of these devices. I can get 50 @ [strike]?4.40[/strike] and pos…
As discussed in the other thread there seems to be interest in getting a consignment of these devices.
I can get 50 @ [strike]?4.40[/strike] and post them out to people.
who would be interested in buying some? These are the 1 Amp ... -
Need some advice about electronicsI have wired up an ATX power supply to power my spectrums through a DC-DC converter that gives 9V from the +12V rail. It works well. However, I also …
... power my spectrums through a DC-DC converter that gives 9V from the ... -
Using an ATX power supply - Spectrum 48kOK... I have an Issue 3 48K model and the DC-DC converter does not work and I can?t make it work. :( There is a MOD to use an ATX power supply on the…
... 3 48K model and the DC-DC converter does not work and I ... -
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…
I 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 modifying R1 and R2?
is there some better solution? -
48K misplaced coloursHello to everybody! Slowly recapping a otherwise working Issue 6A 48K. All new caps aroud LM1889, 7805 and DC-DC converter, which improved ripple an…
... caps aroud LM1889, 7805 and DC-DC converter, which improved ripple and noise ... -
Harlequin Rev. G - error of labels at J16Hi, a German user found an error at Harlequin Rev.G board regarding the labels of J16. The labels of -5V and +12V are interchanged! That could be …
... dangerous, if anyone connects a DC-DC-converter to J16 and plugs in ... -
Timex Computer 2048 restoration projectHi All, I would like to share with you my restoration project of a broken TC2048. Make the story shorty it was my first computer in late eighties …
... the voltage regulator with a DC-DC converter and re-capped the unit ... -
+2/+3 replacement power supplyI'm getting a black keyboarded +2, it has no power supply so I'm trying to source a possible equivalent if i cant get a genuine one, I know an atx s…
... -12V-suply-Q-60B-ac-dc-converter-good/1981293734.html?spm=2114 ... -12V-suply-Q-60B-ac-dc-converter-good/1981293734.html?spm=2114 ... -
Modifying a speccy to +5v only operation.Just a thought experiment so far. Let's say i wanted to make a more resilient spectrum by getting rid of the DC-DC converter circuit. This would remo…
... by getting rid of the DC-DC converter circuit. This would remove the ... upper pin 22/23 (12v DC / 12v AC).
I would ... -
48K power supply coilHi guys, been thinking about making a small quantity of PSU coils for the original 16/48K machines. My problem is, although I can (and have, with gr…
That whole part of the circuit is there just to generate the -VE supply for the memory, right? - Why not do away with it completely and use a more modern dc-dc converter module?
MikeW -
Portugese SpectrumI've just acquired a Speccy 48K which states "made in Portugal" on the back. I thought Portugese "Spectrums" were actually some illegal copy of a Tim…
... ... In my two models, the DC-DC converter oscillator is replaced by a ... -
Multiface 128 problemHello everyone i have a 48k plus speccy which i firstly thought was working perfectly. It passed all the test of the official Sinclair test tape (cpu…
... whole circuit with a small DC-DC converter module?
MikeW -
Interface 1 electrolytic capacitorsInterface 1 has three 47μF electrolytic capacitors. Is it necesary to replace them with fresh ones? I always do this with old speccys but is it…
... Speccy are those from the DC-DC converter. I'm still using my ... -
Interface 1 electrolytic capacitorsInterface 1 has three 47μF electrolytic capacitors. Is it necesary to replace them with fresh ones? I always do this with old speccys but is it…
... ...:D).
Not only the DC-DC converter capacitors, i replace all electrolytic ... -
Interface 1 electrolytic capacitorsInterface 1 has three 47μF electrolytic capacitors. Is it necesary to replace them with fresh ones? I always do this with old speccys but is it…
... ...:D).
Not only the DC-DC converter capacitors, i replace all electrolytic ... -
128k heat sink - ULA problems and a hintHello, I had two ZX Spectrum 128k with a similar behaviour. One item worked only a short time after switching on and then there were increasing RAM …
Wow, I didn't know about that little DC-DC converter module. Personally, I'd still make my own module because I have the kit to do it, but if you can't do your own SMD stuff that looks like the way to go. -
Broken ZX Spectrum? :(Hi! I bought a 2nd hand ZX Spectrum half a year ago. It worked perfectly fine when I first tried it. I put it back in its box which it was sent in, …
... . It's caused by a DC-DC converter that uses TR4 and TR5 ... -
ZX Spectrum Power SupplyHi All, I've come across a power supply that is currently registering 14.5v before it is plugged into the Speccy. I have another one that registers…
... excessive voltages will destroy the DC-DC section which runs off the ... direct +12 supply or another DC-DC converter Or create some horrendous /YUV ... -
Spectrum 48K with a thyristor PSU possible?Is it posssible to use a Spectrum 48K with a thyristor switched PSU? I have a PSU with a thyristor, 4 diodes, one electrolyt capacitor, some resistor…
... the schematic for a small DC/DC-converter.
Not to be confused ... -
Spectrum 48K with a thyristor PSU possible?Is it posssible to use a Spectrum 48K with a thyristor switched PSU? I have a PSU with a thyristor, 4 diodes, one electrolyt capacitor, some resistor…
... the schematic for a small DC/DC-converter.
Not to be confused ... -
Where is the other side from the ZX 48 PCB?Has anyone the other side from the PCB? [url]ftp://ftp.worldofspectrum.org/pub/sinclair/technical-docs/ZXSpectrumIssue3-PCB_Bottom.gif[/url] Micky
... , and a YPrPb to RGB converter instead of noisy composite video ... two things would render the DC-DC converter useless and simplify the overall ... -
7805 Regulator HelpI am hoping to replace the 7805 regulator in my issue 3 48K Spectrum soon. Unfortunately I don't know exactly what to buy to replace it with (my fat…
... ]
It is a DC - DC Converter. A transformator is AC - AC ... -
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…
... all transistors in the switching dc/dc converter. The 4116's survived, as ... -
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…
... and chuck in a proper DC-DC converter module for the 12v needed ... -
Spectrum 48k PSU voltageI have been running into problems with my rubber key speccy. To cut a long story short I did a voltage check of my power supply. It seems to fluctuat…
... it will do to the DC-DC converter section.
Someone in ... -
Amperage drastic reduction in a rubber 48KWell, I am now with the approach of a drastic reduction ZXSpectrum amperage. As a first step would change the Z80 processor for other (Z80C). Unfortu…
... supply circuitry and fit a DC-DC chip with a 5v output ... , However, you can replace the DC-DC converter section with a dedicated 5v ... -
Amperage drastic reduction in a rubber 48KWell, I am now with the approach of a drastic reduction ZXSpectrum amperage. As a first step would change the Z80 processor for other (Z80C). Unfortu…
... , However, you can replace the DC-DC converter section with a dedicated 5v ... is to re-route the DC input voltage (from battery in ... the video circuitry. Then with DC-DC converter in place of the 7805 ... -
Spectrum not working, can anyone help this lady?[URL="http://www.retrogamer.net/forum/viewtopic.php?f=6&t=29734#p674152"]http://www.retrogamer.net/forum/viewtopic.php?f=6&t=29734#p674152[/URL]
OK. Then I can assume that the DC-DC converter is working. If every time you turn it on, the border is white, I'd say you likely have a damaged chip from the RAM at low bank. Less likely a problem with the multiplexers or the RAM at high bank. -
Spectrum not working, can anyone help this lady?[URL="http://www.retrogamer.net/forum/viewtopic.php?f=6&t=29734#p674152"]http://www.retrogamer.net/forum/viewtopic.php?f=6&t=29734#p674152[/URL]
... I can assume that the DC-DC converter is working. If every time ...
