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Whites are yellow - 48k Issue 2I have a 48k issue 2 that appears to be working fine. I've replaced all but 2 of the electrolytic caps (mostly because the 2 were not in stock at my…
... more efficient replacement for the 7805 as detailed here:
http ... .uk/2014/11/zx-spectrum-voltage-regulator.html
The heat sink ... -
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…
... as the 7805 doesn't need to drop as much voltage :)
I mean, with this second voltage regulator are we getting more than ... -
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…
... /discussion/44637/zx-spectrum-pre-regulator-design
BITD, ... one design for a pre-regulator circuit. This is some ... heat dissipated by the 7805 internal voltage regulator and heat sink.
regulator available for purchase from ... -
Modern PSU: picture improvement?I've recently seen advertised some 'replacement power supplies' for Spectrums for which the claim is made that they may make an improvement in pictur…
... Sinclair PSU, yes the 7805 series voltage regulator will dissipate less power as ... polarity if DC. And the voltage rating (and range)
Issue 3b boarddiode ID5 and cap C47 are missing from my board will these have any effect on system powering up. I have checked the voltages on the 7508 and its …
... and output pins of the 7805 5V voltage regulator? I can only think ... reduce the heat from the regulator. But a 330 ohm resistor ...ZX Spectrum issue 4B acquiredI recently acquired a ZX Spectrum with serial number 138-363292 on the case, and a 1983 issue 4B board I got it for the purpose of repair. and have…
Have you checked -5V & +12V lines and transistors there?
I would also go for a replacement of 7805 (the 5V voltage regulator) with a dc/dc 1A converter like R78, TSR1 or OKI-78.ZX Spectrum issue 4B acquiredI recently acquired a ZX Spectrum with serial number 138-363292 on the case, and a 1983 issue 4B board I got it for the purpose of repair. and have…
... for a replacement of 7805 (the 5V voltage regulator) with a dc/dc ... .
I have considered the 7805 replacement, and will look into ...ZX Spectrum 48k output yellow and jumpyI have a ZX Spectrum that I modded for composite output a few years a go. Lately they output started to be a bit jumpy during the first half hour. Th…
... capacitors and taking away the voltage regulator (7805) and installing instead a DC ...Spectrum 48k Power Supply?Guys - I've got a Spectrum 48k inbound from the UK. I want to scrounge a power supply to use when it arrives. What size jack did it use and what ar…
If you replace the 7805 series voltage regulator (I dislike the term linear, ... as voltage regulators have very non ...Spectrum 48k Power Supply?Guys - I've got a Spectrum 48k inbound from the UK. I want to scrounge a power supply to use when it arrives. What size jack did it use and what ar…
... ;896619"]If you replace the 7805 series voltage regulator (I dislike the term ... linear, as voltage regulators have very non ...Spectrum 48k Power Supply?Guys - I've got a Spectrum 48k inbound from the UK. I want to scrounge a power supply to use when it arrives. What size jack did it use and what ar…
... ;896619"]If you replace the 7805 series voltage regulator (I dislike the term ... linear, as voltage regulators have very non ...How many interfaces can be paired up together (as a combo) on the Speccy's back edge connector?Well some would say none as it puts too much of a power strain on the Speccy's power supply . So ignoring this aspect the same question can be asked …
The +5V voltage regulator (7805) inside the Speccy is 1. ...How many interfaces can be paired up together (as a combo) on the Speccy's back edge connector?Well some would say none as it puts too much of a power strain on the Speccy's power supply . So ignoring this aspect the same question can be asked …
... /> [quote="Claudius;897442"]The +5V voltage regulator (7805) inside the Speccy is 1 ... lines there. [/quote]
Most 7805 voltage regulators are rated at 1A ... expansions have their own +5V regulator, so actually use current from ...128K + Toast Rack getting quite hot?Just wondering something if someone can put my mind at ease After using my 128k for around 10 minutes+ it seems to get quite warm around the heatsin…
Did you change the regulator with a 1.5A rated ... did you install a standard 7805 which is rated 1A only ... down, you could replace the voltage regulator with a modern DC-DC ...128K + Toast Rack getting quite hot?Just wondering something if someone can put my mind at ease After using my 128k for around 10 minutes+ it seems to get quite warm around the heatsin…
... is 7805 1A rated. Anyway LM78xx is not an efficient voltage regulator and ...Opus Discovery "the big switch on" (after 20 years)I have a few of these Opus Discovery's with different Eproms in that have not been swiched for 15-20 years or so . I am in no rush to switch any on …
... output current.
7805 voltage regulators are designed for ...
The LM317T adjustable voltage regulator is designed for upto 1 ... set the output voltage to whatever voltage you want (within ... the choice of which voltage regulator to use very much ...Replacing voltage regulators - need to sanity check a few things pleaseHi Everyone I'm in the process (with a lot of help from some friends at Greenford Computer Club), of giving my three Speccys some much needed prev…
... confirm what variant of 7805/78S05 regulators are in ... 7805 (or equivalent), so a 1A 5V DC/DC converter / switching regulator ... 5V DC/DC converter / switching regulator would be suitable.
... the case (the 78xxx series voltage regulator), the inside of the ...PowerI am looking for a Zx Spectrum+ power supply and a cable to monitor. Does someone have one that they do not use, and want to give it away, I cannot …
... for the internal 7805 type regulator. Any higher voltage just means more ... heat loss in that regulator, ... supply of a suitable voltage but rated for more ... damaging the Spectrum. So check voltage & polarity with a ...Power supply voltage regulator circuitRelating to [url="https://www.worldofspectrum.org/forums/discussion/56142/"]this topic[/url] I have managed to acquire this little accessory, which I…
... org/wiki/Voltage_regulator#Transistor_regulator"]Zener regulator[/url] to me. You ... b] pre-regulator to make the Speccy's 7805 happier.
This type of voltage regulator is ... of a ripple voltage on the regulator's input is ...What % of WOSSERS use "old school" tape loading when playing their Speccy games.My guess is .000000001% ( but I might be slightly out on this! ) Do people still enjoy doing it "the old way"?
... only one 7812 three terminal voltage regulator chip (for the +12V supply ... design. It uses a uA723 regulator chip (in a 14 pin ... your Spectrum has had the 7805 replaced with a DC/DC ...Finding a good (UK) external switch mode power supply for the basic 48k and 128k ZX SpectrumsThis idea has probably "done the rounds" by now . I think I have heard about it a bit late . This thread with look at replacing the original "heavy l…
... separated from the low voltage secondary winding by being ... capacitors and a new voltage regulator (7805 or DC/DC converter).< ... to correctly regulate the output voltage, it is possible that ... to replace the 7805 three terminal voltage regulator with a modern ...Help request for an injured Issue 4A spectrumHi folks, I'm hoping to resurrect an issue 4A spectrum that has been in my hoard for a couple of decades since buying it for spares. Someone ha…
About the Disciple heat problem.I was wondering if anyone knows how to solve the problem that Disciple interfaces have that start losing it after some time of usage. I know that the…
... with a sinkcooler on the voltage regulator but I don't know ...Did all Spectrum 128Ks have that large heatsink?Question as per title. I can't seem to find the answer to this. I'm sure I've seen a picture of one without it. Would this be because someone has car…
Question as per title. I can't seem to find the answer to this. I'm sure I've seen a picture of one without it. Would this be because someone has carried out a voltage regulator mod in order to do away with the need for it?+3 PSU PoorlyI have a +3 that just stopped working. Its the psu thats gone and opening it up discovered a blown fuse. After replacing the fuse it still doesnt wor…
... on it. Looks like a voltage regulator. Has anyone got one of ...4164 and 4864 ChipsI have a stock of 4164, 4864 memory chips and 7805 voltage regulators if anyone needs them. Cost would be ?1.50 each plus postage for anyone on here…
I have a stock of 4164, 4864 memory chips and 7805 voltage regulators if anyone needs them. Cost would be ?1.50 each plus postage for anyone on here!
They are mainly 20ns
RichFaulty 128 toastrackHello, I hope someone of the hardware gurus can point me in the right direction for fault finding. My speccy crashes often (sometimes after a short,…
... before (apart from changing keymat, voltage regulator, applying the video fix or ...Help with broken SpectrumHi There, Just received a ZX Spectrum computer. It's an issue 3B (48k version). When I power it up (9V centre pin -V) nothing happens. It's complete…
ZX Spectrum 48K, issue - works fine till it gets hot (?)ZX Spectrum 48K, issue 2, works just fine, tested with Winston's diag board. At a certain moment in time however, it seems to run hot and stalls. Whe…
... the same problem.
Voltage regulator and ULA both get very ...2 48K speccys dead..Hey guys! I've got two of our rubbery friends with me that need some help. They've been like this for some time, but I would like to try and fix th…
... though it might be the voltage regulator at first but all the ...
