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    powering a cordless drill with PSU in drill press DIY build

    Thanks for the replies. I did have at one time,a treadmill motor but no longer & I don't fancy my chances of getting another at low cost. To dave9 I think it's unlikely that a drill stall will occur, generally you'd have nouse to back off & even corded drills can stall but mostly don't burn...
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    not so cordless drill

    An old post I know. But some info I have gleaned while thinking along similar lines: Good cordless drills can almost match corded drills in power output. Typically a corded drill is rated around 450W, depending upon type brand & size. If a PC ATX PSU is considered you are limited to 12VDC &...
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    powering a cordless drill with PSU in drill press DIY build

    Prompted by several DIY builds on YouTube I decided that I should build a drill press. All the examples on YT used a budget commercial corded drill, generally single speed typically valued at about $50. I happen to have a 24VDC battery drill for which batteries are no longer available. So I...
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    Changing out Electrolytic Caps for Polymer Ones

    Again I note the disparity of views on the subject of caps, their properties, construction, typical use, specs & interchangeability. Not sure why the OP needed to use a reflo station for cap replacement, or even if the caps needed to be board mounted. And how did he determine the caps had...
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    Hello, Welcome! (Introduce yourself)

    I'm "newish" here & I guess I don't properly yet know the ropes. Today I received this message: "peterlonz, carlsweden replied to a thread you are watching at Electronics Forums." problem now is; I see no way (after experimenting for some time) of accessing this message. Some guidance...
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    14.4 V Lithium battery - re-purposing question

    Thanks to those kind folk who responded.Answering some of the questions: 1) The battery does have 5 "slots" but it appears only 3 actually have the sliding contacts to allow a male part to engage. 2) I had supposed 2 slots were for discharging to a power tool. One was to monitor battery...
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    14.4 V Lithium battery - re-purposing question

    I have a portable power tool battery, Lithium-ion, brand Einhell, 14.4V, 1300mAh. This battery, though maybe over one year old, has seen no use. The tool (drill) & original battery & charger are not compatible due to model/design changes . So I figured why not use this battery as the basis of...
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    240VAC Transformer based 12 VDC PSU - Problem

    It appears that opinions vary widely on the use of tantalum caps. If they are recommended in application notes from a recognised manufacturer, I can't see a good reason to steer clear, particularly as here I think we are still talking about a 12V LDO regulator?
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    240VAC Transformer based 12 VDC PSU - Problem

    Been wondering why I ever chose an LDO Reg in the first instance. Would not a plain Reg do the job, although I guess regulation losses would be about the same? No idea yet if a tantalum would still be required? Also to spread the loss inevitable in such a design would it not be wise to now fit...
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    240VAC Transformer based 12 VDC PSU - Problem

    I had read the specs but to some extent they are contradictory (on the tantalum output caps) & I note only the spec summaries show Max Vout as 18V. Compare page 2 spec sheet statement: "Maximum Input to Output Voltage Differential: LM1085-12 =18V" (IE a differential). Anyway I am new to this...
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    240VAC Transformer based 12 VDC PSU - Problem

    Output of tranni measured on AC scale DC scale not considered. I am referring not to a plug pack but a conventional transformer. Clear well lit pics very hard on ordinary phone camera, particularly with point to point wiring - it looks a bit like a rat's nest. My next build I will allow more...
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    240VAC Transformer based 12 VDC PSU - Problem

    " but before we continue answer the earlier Q's of mine " Ok here goes: 1) Transformer Vout (no load) = 12.9-13.0 VAC 2) Regulator, under no load: Vin = 16.8VDC; Vout12VDC 3) Across smoothing caps (Reg disconnected) = 17.4VDC PSU on only long enough to take readings but no heat build up at Reg...
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    240VAC Transformer based 12 VDC PSU - Problem

    The case cover (top & sides) is aluminium; chassis front,back & base is 16 mm plywood. The aluminium portion is connected to mains earth for safety as is transformer chassis. I doubt this is an LDO oscillation problem, or that the heat sink was being touched because this was a fairly sudden...
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    240VAC Transformer based 12 VDC PSU - Problem

    OK, sorry about delay in responding. Mislaid my original file on this build. It's point to point wired so pics may not help much - working on that anyway. Meantime details are: As-built details: Wiring: Point to point (no Circuit board) Mains supply 3...
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    240VAC Transformer based 12 VDC PSU - Problem

    Hello, I have just discovered that my "trusty" DIY PSU no longer outputs 12V. I see in fact about 0.5V The unit has been very reliable over the 6 year in intermittent operation; until now. I removed the cover & quickly found (under no load) the LM1085 IT-12 regulator (3A, fiixed 12V LDO output)...
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    ID glass cartridge fuses ???

    Steve & others, Thanks for the replies. Withe the info provided, together with info from other posts on fuses, I think I can proceed safely. I remain uncertain about fuses that carry only a current rating, with plain wire filament, what are these most likely to be? I noticed on another post that...
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    ID glass cartridge fuses ???

    The markings I see are not sufficiently distinct that I can say with confidence what they are. About half are clearly rated 250V, the balance seem to have zero info on voltage. Some of the current ratings are reasonably clear But many are not. I am using a jewelers magnifying glass to get a...
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    ID glass cartridge fuses ???

    I am just putting together a fairly simple Power supply. 240VAC mains powered with DC - DC converter. Max output 24VDC. Max current about 5A DC. I have accumulated quite a number of glass fuses of various sizes. But now I come to choose the best rating & size for my job -Horror - I ca't read...
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    Laser Beam Timer

    Bearing in mind that some form of reliable photographic evidence of the winner, especially in close finishes, will almost certainly be required, I think the video camera suggestion is likely the best. Of course this alone will not provide the winners time which might or might not be important...
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    More woes driving LEDs via PWM

    I'm confused; did you initially intend to merely drive the LED arrangement; you imply the Arduino was an attempt at a solution. So the question might have been why don't the LED's light up when supplied with the specified voltage & (constant) current - obtained from the makers specs? Why turn on...
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