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  1. marcophys

    A Recalculate a range by variable 'Median'?

    Point taken. Clearly this one was over the hills and far away. I don't mind ... it's always good to try to push past the limits, because it is in that way that we find ourselves setting new limits. Thanks again, for your time :smile:
  2. marcophys

    A Recalculate a range by variable 'Median'?

    Thanks for the reply pbuk :smile: Apologies for certain omissions ... and thank you for your median equation. I simply totalled the population groups and divided by 2 (mimicking the method that is often quoted). The Data Set The data set population is * 1000, to match the 'State Count'...
  3. marcophys

    A Recalculate a range by variable 'Median'?

    Hello everyone :) I'm struggling to wrap my head around recalculating a data set based upon median. The data set represents a fixed distribution pattern of population to income group. There is no data available for 'population to income group' at differing medians, hence we accept the...
  4. marcophys

    Can glucose combine with sodium bicarbonate?

    Following up on your request for a list of published studies, I have put together a short list. I've pulled key statements from each, to provide a rapid overview to go with the titles. The first four involve oral administration, and therefore directly pertinent to the question. The fifth...
  5. marcophys

    Can glucose combine with sodium bicarbonate?

    Yes; but the buffering is not inherently stable - probably from the age of 50 onwards (or whenever it becomes unstable). Bicarbonate is produced by the kidneys as a buffer against excess acidity in the blood, and is capable of performing this task until the kidneys decline in function (and then...
  6. marcophys

    Can glucose combine with sodium bicarbonate?

    Here's one that might be worth a read. http://cancerres.aacrjournals.org/content/76/6/1381 There are a number, but I've closed everything down ... time for zzzzz. I didn't spend any time studying the details. Primarily, I was looking for general published support for the assertion. ... it was...
  7. marcophys

    Can glucose combine with sodium bicarbonate?

    I fell upon an article outlining the general health benefits of a balanced pH, and specific anti cancer benefits. ... both concepts are well supported in published studies. The article then went on to describe a protocol, whereby sodium bicarbonate is dissolved in liquefied honey. The principal...
  8. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Ha! Not this time :biggrin: I do provide general engineering knowledge - particularly specific tips for universal application. Here's one I put up two days ago that I did live. Putting it all on the line helps students believe in themselves :wink: So as you can see, the project is a small...
  9. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    I do agree. The knowledge at our fingertips is... enabling. I struggle for words to describe this dramatic change that we have witnessed I make sure that I contribute... the engine rebuild is also being shared.
  10. marcophys

    What's the purpose of this dual coil?

    It's an offshoot from the turntable thread. I was tidying up all the mess (trying to move on) :biggrin: ... and I found this dual coil, with only two cables. I thought, before putting it away, I'll find out what it does. After some feedback, I figured it was safe to test on the window winder motor.
  11. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    It is very possible that a windscreen wiper motor would be better. Of course, I am very happy with our project as it is... the difficulty is deciding when to stop learning. For the brain, it's no longer a question of the specific 'here & now'. ... it's more like "oh... so below a certain...
  12. marcophys

    What's the purpose of this dual coil?

    I may be confused, but... https://en.wikipedia.org/wiki/Electrical_ballast indicates that this is the purpose of electrical ballast. I noted a crossover between choke and ballast - choke ballast. This may be correct or incorrect. Perhaps if we knew why, what was happening to the current, as it...
  13. marcophys

    What's the purpose of this dual coil?

    I just tried it in series with a motor. The PSU puts out 19v DC no load. With the motor running, it drops to 7v. It can be dropped down to 4v and still run. With the coil in series - still 19v no load. With the motor ON the voltage drops to 4v but no sign of life from the motor. Therefore it...
  14. marcophys

    What's the purpose of this dual coil?

    Yes... specifically blue & red - reading 2.3 Ω This is what confused me. Only two connectors (each end of the windings). Almost no resistance. Yet cabled blue and red (traditionally +ve -ve). I looked up choke, but so far, enlightenment has not arrived. ...Ah... but electronic ballast...
  15. marcophys

    What's the purpose of this dual coil?

    What's the purpose of this dual coil? It has a blue and red cable. It stood alone, mounted (isolated) on the chassis of a PC PSU. It's in good condition, so I'm keeping it, but what can be achieved with it?
  16. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Here's one that will fit... found in the PC PSU. The alloy is 5mm thick, 70 x 70. Re the heat paste. I found it amazing that 30 year old paste around a stereo chip was still a paste under the skin. However, I'm glad to know that silicone grease works, as I have plenty of that.
  17. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    The Lamp Modification This went well. There is another gain in motor operation. I ran the motor down to 7 rpm - I think that is the lowest yet seen. The difference is marginal, but worthy More Motor Knowledge Here's the pre-amble explaining how the knowledge was acquired: Lamp The lamp shines...
  18. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Actually... it is hours. I hadn't timed it... but it was switched off for hours. I looked down and thought hmmm that LED is still glowing. I flipped the switch to ON... the LED brightened and died. Development Pause - thoughts and observations With the product apparently developed - a pause...
  19. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    A warning about the CGS HA50 It gets hot... enough to cause a blister. So it definitely needs a safety guard. Also, the suggested lamp mod! It will be a good indicator that the system is powered. You run some tests, write it up, do something else. The motor isn't turning... so it is very...
  20. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Not boring at all. Moreover, very pertinent to the discussion. RE the LED across the capacitor. With the supply cut to the charger... the LED remains illuminated for a long time - 15 minutes at least. I'm guessing that this is due to the presence of two 680 uf capacitors. To drain the...
  21. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Here it is with an LED added and the diagram updated. The LED glows while the motor is drawing current, and is just slightly illuminated when live. ... but what's also interesting (and put a smile on my face) :biggrin: The LED varies the glow according to how hard the motor is working. If the...
  22. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    That's the info I was looking for... how it should be wired. I've drafted the wiring diagram as it currently stands, and added a bridge to the polarity switches. This was also the info I was looking for. It explains everything to me. I now understand why one side of the bridge rectifier was...
  23. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    That's fantastic information Jim. I really appreciate the sharing of that knowledge. I will never again disconnect the battery before switching off the battery charger. For the motor control, we now have two capacitors - one in the charger, the other across the RBV DC output. As it is currently...
  24. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Yes... if only the search for truth was not a dangerous area of interest. However, confusion does have additional benefits, as it stimulates discovery in areas that otherwise might have been missed. I gained knowledge of my DMM, which is very useful for future metering. ... but the error threw...
  25. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Ha!... good idea. Just checked a 1.3V DC battery... it shows a lovely 2.4V AC. I guess that confirms it :frown:
  26. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    No... it's digital. Sadly, also no!. I've just measured the charger output on Lo (with capacitor as per drawing) = 39V AC - 17.8V DC It remains stable within 0.2V for a minute. On Hi the output is 44.5V AC - 20.3V DC Note... It's Sunday evening: Mains supply is fluctuating between 230V -...
  27. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Absaar 108 NE/D2 12V Battery Charger With added capacitor for motor load Image Notes The image seems to have been re-scaled. Even opening in a new tab fails to show the image at full size. The only unreadable element is the capacitor spec: SAMXON 680 µF 200v LP (M) 85 deg Charger Notes...
  28. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Understood. It's the universal difficulty in documenting change. ... the current status as compared to previous status (and maybe in the same post, a mention of the planned mods). Of course, the writer knows what's happening, but as for everybody else... RBV 602 bridge rectifier...
  29. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Ah... so we are not completely in the dark :smile: Wrapping up what we have achieved Motor control panel As you can see... I fitted the resistor onto it's heat dissipating aluminium bracket ... and then fitted the bracket to it's natural place, only... The plug flex would tend to lay on the...
  30. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    I have changed the wiring of the internal capacitor. It is now wired across the output -ve and the +ve entry to the fuse, similar to Jim's recent suggestion above. Result This worked. I then wired in the 2nd capacitor after the RBV. The motor was slowed to 6.5 rpm. I then disconnected the 2nd...
  31. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Well... I wired it as per your photo: "Trial and error is the approach for this one. See if a 40 watt 12 V lamp on secondary behave noticeably different from a 40watt 240 volt lamp on primary ? To avoid rectifier drop he could connect it here" It shows 12V AC with dimmer feed... so it is in...
  32. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Ha! No... it was a failure. (Damn... I spent an age creating the wiring art) :biggrin: Result The moment that I switched the motor on... I knew. The first thing was that it wouldn't start - it needed more power. ... then the sound. I had another capacitor, so I quickly placed it after the...
  33. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Thanks Jim. But to be fair, it was alarm & confusion that was the driver. Seeing AC everywhere on my meter. I needed this confirming, not only for this project, but for future metering. It seems that you are right - my AC meter shows just over double the DC value, even after passing through the...
  34. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    I fitted the RBV 602 to the output - the two centre pins. The two outer pins (marked + - ) delivered similar readings... AC just more than double the DC. I presume that this confirms that something is amiss with my meter. Anyway, having got the rectifier... I'll see how it works with the motor.
  35. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    I've metered it again, on both fast and normal charge (without capacitor across output). in both cases AC is showing slightly more than double the DC. Re the capacitor. I've found a couple of 50V 0.1 µF capacitors. I also came across an RBV 602 bridge rectifier...
  36. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Thanks Jim. I was merely reading the meter @ AC & DC settings. ... but let's see what happens with your tests. All readings below taken on Mains supply fast charge setting no load DC output = 13.5 V AC output = 29.1 V capacitor connected across output DC output = 20.6 V AC output = 44.8 V...
  37. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    ... or is it? Tidying The Loose Ends The 2 speed motor We never discovered how the motor reduced speed when it's polarity changed. Jim put it down to mechanical or electrical wizardry :smile: That's a perfect holding position for the moment. The spare motor/drive will be opened in the near...
  38. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Yes... that halogen lamp is even smaller, and would sit rigid between solid cores :) Alternative to the lamp concept CGS HSA50 1.8k Ω resistor Typically used as demister heating elements in camera housings, beneath the glass face of the housing. I do believe that somewhere I have a spare...
  39. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Final test of this session Confirm the need for the dimmed mains supply 'solution'. With the capacitor wired in parallel with the DC output & the 40 watt lamp in parallel with the dimmed mains supply ... ... the motor was slowed to absolute minimum, yet could be stopped and started. By...
  40. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    SAMXON 680 µF 200v LP (M) 85 deg (has polarity) This was a major success vis a vis visible effect. Test Method - Lamp & Capacitor With 40 watt lamp across the primary The motor was slowed to the absolute minimum. If stopped... the motor could just restart. The capacitor was placed across the...
  41. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Notes on the popped capacitor LTEC LZG 105 deg PET 8628D http://www.compostar.com/Ltec/LZG.pdf It had seen use in a PC PSU. The top was flat when tried. I'm wondering if I could have damaged it during soldering. I'll look for an alternative.
  42. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Further thoughts... and note that the capacitor failed in the edit above. Transformer Sound Clarification With the ear on the transformer chassis: When powered by standard mains supply The transformer hums. In addition: there is also an inconsistent minor ticking When powered by dimmed mains...
  43. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Okay, the 5A is implemented :smile: Found a 330 µF 25v capacitor on the PC PSU board. It was difficult to desolder. The solder cooled instantly before the solder pump could work :frown: ... but got it out. 330 µF 25v capacitor across DC output This had a similar noise reduction effect to the...
  44. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Pauses in development are useful. They are usually caused by external forces, but in fact they are anyway required. I must clear up something else tomorrow, and then I'll get back on this. I'll implement the fuse as suggested, and then look again at resistive loads. I have the typical 240V...
  45. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Thanks Jim! Yes... development engineering is most definitely fun. Fine to take a drawing and bring it to life... that hits a different pleasure receptor. ... but creating something, and solving the problems that are encountered, is simply unbeatable. The final stages are upon us. The turntable...
  46. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Great. Two lamps in the battery charger enclosure would indicate that it was on! However, I am interested to understand the difference between a lamp filament, and a resistor. IE. is the resistor idea wrong? The reason being that I don't have a small 240V lamp. Neither do I have the resistors...
  47. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Just reading up on resistors: It seems that I would need one rated at 400v. If: Current I = V/R 240/1000 = 0.24 Amps Power consumed P = I2R = 0.242 x 1000 = 57.6 W 10K Ω would consume 5.76 Watts. 100k Ω would consume 0.576 Watts Is this correct? I wonder if the resistance could be even...
  48. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Yes, TBH I was thinking about a resistor bridging the dimmed output (resistive load). 100W or 40W lamp seemed to make no difference. Perhaps if the wattage reduced significantly... I think that I have an 8W lamp - or used to have, as it hasn't turned up (and I've been looking). Or perhaps it...
  49. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Wiring a 40W lamp in parallel to the Transformer feed Haha... thanks Tom... it worked! The buzzing dropped substantially - barely perceptible (as you'll see in the video below) You've just jumped the development process... thanks for contributing :smile: Metering the DC voltage The video...
  50. marcophys

    DC12V 12A car window motor - what spec for a 220V PSU?

    Measuring the Dimmed live feed ... at DC setting 200V The reading is up and down, varying from a peak of 1.3V DC to 0.1V DC. This is a repeating cycle, that hovers mid range then goes up... and then down. ... but max is always momentarily 1.3V DC. Therefore well under the 2V DC that you warned...
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