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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…
... /> A final question, for voltage regulator (7805) i used one with the ... -
48K Speccy not workingHey, A few months ago (hope it´s not to late) I was loading a game into my speccy and from one moment to another it stopped working! I unplugge…
... photo i see a power regulator in the top right ... .tkk.fi/Misc/Electronics/circuits/7805.gif[/url]
We ... the following:
1. 7805 is dead => replace it ... only pin 3 of the 7805, powering it up (connecting ... appears on it, then 7805 is good and one of ... -
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 …
... you have killed the voltage regulator only, possibly far worse - ... , and does cover the 7805 VRegs used by the 128K ... />
"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 …
... you have killed the voltage regulator only, possibly far worse - the ... the 7805 afterwards and it checked out fine. If the regulator isn ... -
Voltage SchmoltageOk then. Don't flame for wanting to use a C64 tape deck for this - it was the only one I have to hand which may be cannibalised for the purpose. So …
... sides of the regulator, not just the ... code] +-----+
| O |
+-----+
| 7805|
| |
+-----+
| | |
The regulator only has one output - your ... -
Voltage SchmoltageOk then. Don't flame for wanting to use a C64 tape deck for this - it was the only one I have to hand which may be cannibalised for the purpose. So …
... :) I was thinking that that regulator outputted 12v and 5.7v ... question time, then: what is 7805 actually regulating? both of those ... -
Voltage SchmoltageOk then. Don't flame for wanting to use a C64 tape deck for this - it was the only one I have to hand which may be cannibalised for the purpose. So …
... :) I was thinking that that regulator outputted 12v and 5.7v ... question time, then: what is 7805 actually regulating? both of those ... -
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, …
... /3) is a voltage regulator, the 7805. It's a pretty easy ... inside the Spectrum is another regulator, only this one is a ... ".
Note that the 7805 chip (it is an integrated ... than around 7V (for the 7805) reference ground, the device won ... -
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 ... and bypass the 7805 or use another voltage regulator to get +9v ... be enough, so what other regulator?
[/QUOTE]
You ... may use one variable voltage regulator like the LM317T or use ... -
Broken 128+2 :(Just got my eBay Speccy through the other day, plugged it in and everything but the red light on the keyboard doesn't come on and there's no connecti…
... doesn't cure it, the regulator 7805 which is mounted on the ... -
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…
... more heat? Did the voltage regulator have to work harder, thereby ... +128K need about 1A. The 7805 have to supply more power ... -
Of soldering and whatnot.So. It looks like if I'm going to have any sort of active retrogaming habit in the future, I need to learn a bit more about the nuts and bolts. Emula…
... timer ICs.
- A 7805 voltage regulator, and simple wall wart power ... around the house already). The 7805 will give you the 5 ... -
True Spectrum laptop (no emulation)[url]http://user.tninet.se/~vjz762w/[/url] Hi All, I have build a speccy laptop, battery part is not ready yet.... I did it on 2 days, I will put s…
... of the 7805 + your reg, or all in your regulator.
If Cookie is intending to replace the 7805 ... with a switch mode regulator, you'd be ... -
True Spectrum laptop (no emulation)[url]http://user.tninet.se/~vjz762w/[/url] Hi All, I have build a speccy laptop, battery part is not ready yet.... I did it on 2 days, I will put s…
... of the 7805 + your reg, or all in your regulator.[/QUOTE]
7805. When running off the 9v ... to replace the 7805 with a switch mode regulator, you'd be ... -
"Upgraded" broadbandTo cut a long story short, I have just had my broadband speed upgraded from 1meg to 5meg (it was free). Having just spent over an hour setting up the…
... router. Even a humble 7805 linear regulator circuit will do a reasonable ... capacitor (and no, a linear regulator won't inject more noise ... the mains. A switch mode regulator may well do, though - they ... solved and off the shelf regulator ICs will do the job ... -
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 …
... that (although a 90% efficient regulator sounds great!)[/QUOTE]
7805, but I would have to ... anything more than desoldering the 7805 and soldering a 3 pin ... -
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 …
... />
Place an additional 5V regulator (7805) inside the divIDE+ case with ... divIDE+ and so the 5V regulator inside spectrum has lower 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…
... check of voltages, new voltage regulator, new membrane... Also added a ... better voltage regulator that can be used instead of the 7805 type ... to add an additional voltage regulator in case one fails (have ... -
48k + Power supplyHi, Anyone know where I can get a replacement PSU for the 48k Plus? Nothing on Ebay at the minute. Looks like the end is Imminent for my one! Tha…
... get converted by a lovely 7805 to 5 volts at 3 ... onto the +5 (where the regulator would of been.) surely this ... -
ZX Spectrum not working - Please help.Hi there, I am new to this forum and was pointed in this direction by a fellow Youtuber after uploading the following video and then explaining that…
... , suspect a failure in the regulator 7805 or some other section of ... -
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…
... ) switching mode step-down voltage regulator! The use of a transformer ... use it to subsitute the 7805 inside the 48k but you ... -
My Spectrum has gone a bit dud since doing some Mods, HELPMy father in law and I did some modifications to my 48K rubber key Spectrum last weekend, and now it seems to be very keen to crash, especially when …
... ]Control the soldering from the 7805. Because the heatsink can damage ... /> Or a leg from the 7805 has a very fine broken ... on the heatsink. Change the 7805.
Micky[/QUOTE ... ]
Thanks Micky. The 7805 being the regulator I presume? -
My Spectrum has gone a bit dud since doing some Mods, HELPMy father in law and I did some modifications to my 48K rubber key Spectrum last weekend, and now it seems to be very keen to crash, especially when …
[QUOTE=Alien 8;439146]Thanks Micky. The 7805 being the regulator I presume?[/QUOTE]Yes.
Micky -
My Spectrum has gone a bit dud since doing some Mods, HELPMy father in law and I did some modifications to my 48K rubber key Spectrum last weekend, and now it seems to be very keen to crash, especially when …
Make a test and touch the heatsink and the regulator. Move the finger something. If the ZX then crashes it is the 7805. If not then I guess it is the keyboard membran.
Micky -
My Spectrum has gone a bit dud since doing some Mods, HELPMy father in law and I did some modifications to my 48K rubber key Spectrum last weekend, and now it seems to be very keen to crash, especially when …
... touch the heatsink and the regulator. Move the finger something. If ... then crashes it is the 7805. If not then I guess ... another thread that a new 7805 doesn't even need a ... -
My Spectrum has gone a bit dud since doing some Mods, HELPMy father in law and I did some modifications to my 48K rubber key Spectrum last weekend, and now it seems to be very keen to crash, especially when …
... to replace a 7805 with a switching regulator, often this involves ... from damage. With a switching regulator in its place, it' ... wiki/Low_dropout_regulator"]low-dropout[/URL] regulator, and input a [I] ... (around 6~7V depending on regulator type).
Does ... -
Remove +12 Volt itemsWhich items can be removed on a ZX48K issue 4b PCB if I don't need the +12 Volt? Micky
... possibly cause problems. The 5v regulator (7805) is then required to drop ... heatsink to avoid damaging the regulator. -
Remove +12 Volt itemsWhich items can be removed on a ZX48K issue 4b PCB if I don't need the +12 Volt? Micky
... possibly cause problems. The 5v regulator (7805) is then required to drop ... -
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…
... part, replace with another 7805. They are cheap, common ... The 7805 is what's known as a linear regulator, and ... The other common kind of regulator is known as a ... switching regulator (or switch mode power ... solder in where the 7805 used to be, they ... -
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…
... part, replace with another 7805. They are cheap, common ... The 7805 is what's known as a linear regulator, and ... The other common kind of regulator is known as a ... switching regulator (or switch mode power ... solder in where the 7805 used to be, they ...
