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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 …
... to replace it ! Simply disconnect 7805 output pin (the one with ... -
+3 Sound Mod.Hi All, I am very much a novice when it comes to building electronics, but I thought I'd have a go at [url]http://www.geocities.com/sinclair_bitz/st…
... the output.
A 7805 needs at least 7v to ... not correctly feed (well, a 7805 with inverted polarity blew up ... -
ZX Spectrum 48K +Hi, I have a ZX Spectrum 48K + which I bought like a million years ago (1984) My Spectrum has been out of duty for quite some time and I guess I ke…
... out,some transistors inside and 7805 chip.
b)z80 ... -
Does anyone have any working Ferranti's?Does anyone know where I might get hold of a Ferranti ULA5C112E-3?? I think this is the problem with one of my rubber key 48K's as it otherwise wor…
... a bit thicker than the 7805 heatsink) and made many ula ... -
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 …
... series diode (1N4007) from a 7805 regulator ground pin down to ... /> [code] +-----+
| O |
+-----+
| 7805|
| |
+-----+
| | |
+12 ... -
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 …
... /> [code] +-----+
| O |
+-----+
| 7805|
| |
+-----+
| | |
+12 ... -
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 …
... 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 …
... question time, then: what is 7805 actually regulating? both of those ... -
Eprom blowerdoes anyone know a site with plans for an eprom programmer project that'll blow 27C256s. I attempted to build one called Kisseprom, but the software …
... , depending on type.
The 7805 is powered from the external ... -
ZX81 power supplyFriend gives me ZX81 without power supply and i want to test whether he work or not. Can i use Spectrum p.supply for that purposes? I dont want to d…
... , as the ZX81 has a 7805 regulator to bring the input ... -
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, …
... ) is a voltage regulator, the 7805. It's a pretty easy ... ".
Note that the 7805 chip (it is an integrated ... than around 7V (for the 7805) reference ground, the device won ... -
ZX81 power supplyFriend gives me ZX81 without power supply and i want to test whether he work or not. Can i use Spectrum p.supply for that purposes? I dont want to d…
... and "grey" +2.
- Minimal 7805 heat dissipation ! -
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, …
Another thing, is that an unregulated PSU will give more ripple into the Speccy, and so make the 7805 "work harder" to compensate for this, which will lead to even more heat. -
PC Power supply for SpeccyHi all, after 13 years with out playing spectrum games I am eager to play the old games. Thus I got up to the garret checking my old stuff. Two of m…
... peripherials (which utilize regulators like 7805 to make own power out ... -
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…
... the 3rd pin in the 7805 chip is´t the same ... -
I want to build a new, super spectrum ;-)only kidding Andrew :-) my brain's going at a mile a minute at the moment, so I thought I should put some of the ideas down in case one of them is w…
... vastly more efficient than a 7805 regulator, and will generate very ... sink). Having said that, the 7805 is very robust, and provides ... rushing to replace it. The 7805 has built in thermal and ... -
I've got a divIDE. Now what?I've purchased a divIDE and after a month it's at home. What can I do now with that? I've got a 48k+, a +2B and a +3. The +2B has the original ROMs,…
... interface has it's own 7805 reg yes, but the drives ... -
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 ... ), using +5v and bypass the 7805 or use another voltage regulator ... -
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 …
... 9V anyway.
The 7805 regulator needs at least 7V ... -
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…
... supply. If good check the 7805 regulator IC and this +5V ... -
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…
... 't cure it, the regulator 7805 which is mounted on the ... -
Interface rom - Need help to dump itHi, I have temporarily an interface that is similar to a multiface. It has an NMI button and displays a menu where states can be saved and pokes ent…
... . Is it possible that the 7805 is not working correctly? I ... -
Input/Output on Edge ConnectorI would like to sense a pulse on the data bus via the edge connector, i.e. on or off. How do you decide what port it is on? I would also like to send…
One thing you might want to do, then, is get hold of some breadboard - and a collection of 74-series logic, and a 7805 regulator (so you can get 5 volts), a bag of 50 or so 5 volt LEDs and experiment for a bit. You'll find it very instructive. -
Input/Output on Edge ConnectorI would like to sense a pulse on the data bus via the edge connector, i.e. on or off. How do you decide what port it is on? I would also like to send…
... like bags of capacitors, timers, 7805 regulators and various miscellaneous stuff ... -
Look what I got!Look what I just got in the post: [url]http://www.alioth.net/tmp/W5100.jpg[/url] But, please... don't hold your breath :-) Coming to an edge connec…
... me is already on the 7805 for the 5v supply to ... -
Look what I got!Look what I just got in the post: [url]http://www.alioth.net/tmp/W5100.jpg[/url] But, please... don't hold your breath :-) Coming to an edge connec…
... me is already on the 7805 for the 5v supply to ... -
Faulty +2 Grey :(Hello everyone... i was trying to fix a +2 grey board the other day, i had it for some time now. It gave a black screen (paper and border) with two …
... .
Also i tried another 7805 (from the working grey, the ... whole heatsink and 7805 that is screwed on it ... -
Composite Video output problemHi everyone, I?ve got a problem that?s really bugging me. I have one Spectrum 48K and one Spectrum +3, both with Composite Video output modification…
... be a problem with the 7805 regulator that´s supposed to ... -
Composite Video output problemHi everyone, I?ve got a problem that?s really bugging me. I have one Spectrum 48K and one Spectrum +3, both with Composite Video output modification…
... be a problem with the 7805 regulator that?s supposed to ... . It is pushed through the 7805 regulator which provides a stable ... -
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…
... +128K need about 1A. The 7805 have to supply more power ...
