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TIPP31 transistor questionYesterday I had the time to try and repair a 4S issue 48k spectrum I had. First of all I replaced all the electrolytic capacitors. The tr4 transistor…
[QUOTE=gtsamour;187043]
A final question, for voltage regulator (7805) i used one with the indication "L7805CV", is it appropriate?[/QUOTE]
Yes, it this an 7805 regulator from "ST Microelectronics". :-) -
ZX Spectrum 128+ problemsHello!I recently purchased and got myself a spectrum 128+ from ebay.The item did not have an original power supply so i got a power supply of 9volts …
... Possibly you have killed the voltage regulator only, possibly far worse - ... and does cover the 7805 VRegs used by the ... br /> "Reverse polarity destroys the regulator almost instantly. To avoid this ... test' could destroy the regulator if a protection diode is ... -
ZX Spectrum 128+ problemsHello!I recently purchased and got myself a spectrum 128+ from ebay.The item did not have an original power supply so i got a power supply of 9volts …
... . Possibly you have killed the voltage regulator only, possibly far worse - the ... the 7805 afterwards and it checked out fine. If the regulator isn ... -
spectrum PSU'sI've read contradictory info on which psu(ie amp rating) is for which spectrum. :confused: The models and amp ratings are 1.2A, 1.4, 1.85 and 48k, …
... +2a/3) is a voltage regulator, the 7805. It's a pretty easy ... inside the Spectrum is another regulator, only this one is a ... - it converts the incoming voltage to three separate voltages, which ... the input voltage is less than around 7V (for the 7805) reference ... -
PC power source and Spectrums.I'm planning to use a basic PC ATX power source (300W) for all my sinclair equipment, but I have two questions: - I've read about some nasty things …
... +12v and relying on the 7805 (I think it will overheat ... +5v and bypass the 7805 or use another voltage regulator to get +9v ... /> You may use one variable voltage regulator like the LM317T or use ... -
Did the 128 really need that oversized heatsink?Quick question: Did the 128 generate extra heat (compared to the Plus) to warrant the new heatsink? Obviously the machine carried extra RAM and addit…
... generated more heat? Did the voltage regulator have to work harder, thereby ... +128K need about 1A. The 7805 have to supply more power ... -
R.I.P. spectrum 48kRecently one of my 48k rubber key (issue 4) machine bit the dust the other day when I tried to power it on. When powering it on, it gave a weird 'bee…
... , full check of voltages, new voltage regulator, new membrane... Also added a ... a better voltage regulator that can be used instead of the 7805 type ... possible to add an additional voltage regulator in case one fails (have ... -
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…
... (simple) switching mode step-down voltage regulator! The use of a transformer ... the design to provide various voltage outputs.
The LM2576 is ... use it to subsitute the 7805 inside the 48k but you ... -
Maximum number of Spectrum devicesHi! What is maximum number of devices i can connect to my rubber key Spectrum? Is there somekind of limit? Now i have Interface 1, Microdrive, Zx p…
... 8255)
Only internal voltage regulator 7805 i replaced by 3A switching ... regulator. I think, it was not ... -
Zx Spectrum 48k+ black screenHi A friend of mine gave me his 48k+ and when i tried to turn it on I just get a black screen of the TV. I don't have sound of the console. Where c…
... . the ZX spectrum uses a 7805 5volt regulator - its right near the ... .alldatasheet.com/view.jsp?Searchword=7805]click here[/url] as you ... look at replacing the unit - 7805 5volt regulators are VERY cheap ... 'll try to check the voltage regulator as soon as I can ... -
Grey +2 regulatorIv just checked the regulator and its a TS2940. Could someone tell me the equivalent please?
... (Grey) model it is a 7805 5volt regulator.
I have ... co.uk/5-x-7805-1A-Fixed-Voltage-Regulators-/320430515613?pt= ... here: 5x 7085 5volt Fixed Regulator 1Amp
[img]http ... paste/grease/compound between the regulator and the large heatsink ... -
Grey +2 regulatorIv just checked the regulator and its a TS2940. Could someone tell me the equivalent please?
... an original (factory mounted) voltage regulator. Originally should be 78[ ... replaced with a regualr 7805, which is used on ... ZX128 is an ordinary 7805, but in ZX+2 ... pcs) had a 78S05 voltage regulator. If there is a ... 1.5A or 1A regulator (especially non-fixed and ... -
ZX Spectrum 48k issue 3b power problem?Hi :) I was lucky enough to find a couple of ZX Spectrums at a car boot sale yesterday. I spent the evening fiddling about with one (issue 2) and t…
... internally regulated by a 7805 / 78S05 regulator for 5v, this is ... [/B]
The 7805 regulator is the crux of most ... in the chain is the 7805 5v regulator.
reading ... uk/10-X-L7805-Voltage-Regulator-L7805CV-5V-7805-FastPost-/150462834416?pt= ... -
what is this crazy modfound a speccy in my loft yesterday,and it seems to have an external heatsink modd i havent the foggiest about speccys heres a few pics [url]http://i…
... the motherboard and the 7508 voltage regulator (the three pin component) when ... you use a linear regulator like the 7805 you DEFINITELY need a ... -
ZX Spectrum TowerHi all, i am working on a ZX Spectrum 48K build in a PC tower case. Is there anyone who did it before? I have some questions duo the PSU. I have to g…
... -12v/+12v/-5v and a 7805 for the +5v.[/QUOTE]
voltage regulator with a DC/DC converter. I believe the 7805 is ... -
Misbehaving 128K toastrackI acquired a toastrack some time ago off ebay and it worked just nice up until recently. It arrived with no PSU or cables so I paired it with a grey …
... where to start. Luckily, the 7805 replacement is as easy as ... chance of replacing the 7805 with a Recom voltage regulator, would 1.5A ... -
Misbehaving 128K toastrackI acquired a toastrack some time ago off ebay and it worked just nice up until recently. It arrived with no PSU or cables so I paired it with a grey …
... chance of replacing the 7805 with a Recom voltage regulator, would 1.5A ... -
16 colours on a Timex Sinclair 2068I'm putting a few videos up on YouTube, the first one shows the colours on the TS2068. [url]https://www.youtube.com/watch?v=1tJ1qIMcTUE[/url] Brigh…
... +7.5V and use a 7805 linear voltage regulator to drop that +7 ... -
Issue 3 board... How to resurrect?Dear Everyone, Now I have a working 48k Issue 3, a sort of working Speccy+ (still having problems with the keyboard, more of that in another post) a…
... you sure about the voltage readings? With 5V missing ... your meter to the voltage regulator heatsink (as I did ... power on measure the voltage between that and the ... facing you) of the 7805. This should be the ... 5V output from the regulator. If the 5V is ... try a new 7805. -
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…
... would also add the 7805 power regulator as something than I would ... the heat generated in the 7805, add two 3A rectifier diodes ... and helps the 7805 regulator by having to drop less voltage across it ... -
Issue 2 crashes after about 30 minsHi Guys, I have an Issue 2 zx spectrum that seems to get graphic corruption after about half hour of playing, then finally falls over and crashes. …
[U][B]ZX Spectrum Pre-regulator Design[/B][/U]
regulator circuit. This is some ... heat dissipated by the 7805 internal voltage regulator and heat sink.
Instead, the pre-regulator ... -
Didaktik Gama and M manualsI?m looking for manuals for the Czech Spectrum clones Didaktik Gama and M. Thought this would be an easy task, but I couldn?t find any user or servic…
... any number of solutions (SMPS, 7805 etc). For the 20V, since ... get a higher-voltage SMPS and an adjustable voltage regulator, something like an ... -
Toastrack refurbishmentYesterday I opened a drawer in my old desk and discovered 2 complete toastrack 128s and a board only for the same. As I already have a fully working…
... eyes all have 1 amp 7805 voltage regulators.
[QUOTE=jimre ... /> [QUOTE=guesser;780970]With the 7805 regulator switching replacements there's nothing ... ?trip? current, the regulator will reduce the output voltage until the current ... -
Toastrack refurbishmentYesterday I opened a drawer in my old desk and discovered 2 complete toastrack 128s and a board only for the same. As I already have a fully working…
... the +5V rail from the 7805. So as the keypad runs ... , it will not affect the 7805.
As for expansion ... have its own voltage regulator circuits (meaning use another 7805) drawing power from ... -
Burned finger temp on rubber 48k heatsink normal?Ok so i opened it up because a few keys started to act up and i noticed that after burning my hand the heatsink was that hot i could actually smell t…
... here for the switch mode 7805 compatible regulators :)
... 100Hz ripple on it. The voltage regulator
inside the Spectrum ... Does this mean that the voltage regulator has another purpose, besides bringing ... instead of a 'true' voltage regulator? -
Burned finger temp on rubber 48k heatsink normal?Ok so i opened it up because a few keys started to act up and i noticed that after burning my hand the heatsink was that hot i could actually smell t…
... ripple on it. The voltage regulator
inside the ... Does this mean that the voltage regulator has another purpose, besides ... 'true' voltage regulator?[/QUOTE]
Both the 7805 and the ... a voltage regulator circuit. The purpose of a voltage regulator is ... -
Weird symptom number 2...I got a new keyboard membrane for my Spectrum+ plugged it in and low and behold the weird left to right printing of the copyright message disappeared…
... />
I could switch the 7805, could one of you gents ... /p/ts7805cz-1a-positive-fixed-voltage-regulator-to220-case-ql31[/url]
Weird symptom number 2...I got a new keyboard membrane for my Spectrum+ plugged it in and low and behold the weird left to right printing of the copyright message disappeared…
... metal tab of the 7805 regulator is electrically connected to ... ts7805cz-1a-positive-fixed-voltage-regulator-to220-case-ql31[/URL ... ts7805cz-1a-positive-fixed-voltage-regulator-to220-case-ql31j"]http ... -voltage-regulator-to220-case-ql31j[/URL]
Yes, this 7805 ...Switched voltage regulatorIn the past a replacement voor the (hot!) 7805 has popped up a couple of times in various threads. As far as I know, Recom Power Inc. was always ment…
... replacement of the 7805 by a switched voltage regulator can cause problems at ... the fact that the operating voltage of the PSU runs very ... . This will reduce the operating voltage by 0.7V to 12 ...No display on a 128 toastrackHi All, I just bought a 128k off ebay with the usual, "it worked last time I used it", so I read into this "it does not work". True enough, it does n…
... , will normally destroy the 7805 5V voltage regulator and destroy the two transistors ...
