On Sat, 20 May 2017 11:06:50 -0400, rickman <gnuarm@gmail.com> wrote:
>On 5/20/2017 7:22 AM, default wrote:
>> On Fri, 19 May 2017 16:58:54 -0400, rickman <gnuarm@gmail.com> wrote:
>>
>>> On 5/19/2017 3:18 PM, default wrote:
>>>> On Fri, 19 May 2017 10:03:02 -0700, John Larkin
>>>> <jjlarkin@highlandtechnology.com> wrote:
>>>>
>>>>> On Fri, 19 May 2017 06:55:25 -0400, default <default@defaulter.net>
>>>>> wrote:
>>>>>
>>>>>> On Thu, 18 May 2017 08:43:17 -0700, John Larkin
>>>>>> <jjlarkin@highlandtechnology.com> wrote:
>>>>>>
>>>>>>> On Thu, 18 May 2017 07:41:04 -0400, default <default@defaulter.net>
>>>>>>> wrote:
>>>>>>>
>>>>>>>> On 18 May 2017 06:00:58 GMT, Jasen Betts <jasen@xnet.co.nz> wrote:
>>>>>>>>
>>>>>>>>> On 2017-05-13, default <default@defaulter.net> wrote:
>>>>>>>>>> On Sat, 13 May 2017 08:35:23 -0700, John Larkin
>>>>>>>>>> <jjlarkin@highlandtechnology.com> wrote:
>>>>>>>>>>
>>>>>>>>>>> On Fri, 12 May 2017 06:47:01 -0400, default <default@defaulter.net>
>>>>>>>>>>> wrote:
>>>>>>>>>>>
>>>>>>>>>>>> On Fri, 12 May 2017 10:47:54 +0200, o pere o <me@somewhere.net> wrote:
>>>>>>>>>>>>
>>>>>>>>>>>>> On 11/05/17 00:42, Phil Hobbs wrote:
>>>>>>>>>>>>>> On 05/10/2017 02:31 PM, John Larkin wrote:
>>>>>>>>>>>>>>> On Wed, 10 May 2017 09:57:21 -0700, etpm@whidbey.com wrote:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> I have an automatic opening trash can in the kitchen that runs off of
>>>>>>>>>>>>>>>> batteries. I wanna run it with a wall wart. When the lid opens it
>>>>>>>>>>>>>>>> draws more power than the 750 mA wall wart I tried using to power it
>>>>>>>>>>>>>>>> could deliver. This makes sense. I don't want to use a bigger wall
>>>>>>>>>>>>>>>> wart and I don't want to have betteries in it all the time to provide
>>>>>>>>>>>>>>>> the current. I'm thinking instead of using a capacitor. If the current
>>>>>>>>>>>>>>>> and voltage draw as well as the duration to open the lid is measured
>>>>>>>>>>>>>>>> can that not be used to calculate the minimum size capacitor? And if
>>>>>>>>>>>>>>>> not excessive maybe a cap that would open the lid three or four times
>>>>>>>>>>>>>>>> in a row could be used in place of the 6 AA cells it uses now.
>>>>>>>>>>>>>>>> Reasonable?
>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>>>> Eric
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> A conventional cap, no. Maybe a super expensive supercap.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> I wouldn't want an electronic trash can. All that cheap, badly
>>>>>>>>>>>>>>> programmed microprocessor/LCD appliance junk will break in a couple of
>>>>>>>>>>>>>>> years, and be annoying meanwhile.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> *SIX* AA cells? How long do they last?
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> A couple of supercaps in series might work fine. For instance,
>>>>>>>>>>>>>> SCMT22C505MRBA0 AVX CAPACITOR 5F 20% 5V 0.065ohms $5.23000 in onesies
>>>>>>>>>>>>>> from Digikey.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Two of those in series, with a TL431 across each one (set for 4.8V or
>>>>>>>>>>>>>> so) to equalize the voltage, plus a charger with about a 50 mA current
>>>>>>>>>>>>>> limit ought to work, I should think.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Cheers
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Phil Hobbs
>>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>> Is there data on leakage or self-discharge of these beasts? The
>>>>>>>>>>>>> datasheet just says "low leakage current" and this could just mean
>>>>>>>>>>>>> anything...
>>>>>>>>>>>>>
>>>>>>>>>>>>> Pere
>>>>>>>>>>>>
>>>>>>>>>>>> The caps I'm using give the leakage at .16 ma.
>>>>>>>>>>>>
>>>>>>>>>>>> http://www.illinoiscapacitor.com/ic_search/super_products_detail.aspx?icpartnumber=700020
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> 50.625 watt hours???!!!
>>>>>>>>>>
>>>>>>>>>> It's magic, or a decimal point slipped 2 places. 1/2 watt I might
>>>>>>>>>> believe.
>>>>>>>>>
>>>>>>>>> more like 3 decimal places, 0.5*C*V*V/3600
>>>>>>>>
>>>>>>>> I agree. Did the math and posted as much on 5/14.
>>>>>>>>
>>>>>>>> I'm thinking they mistakenly used some "one size fits all" or
>>>>>>>> watt-hours per X farads.
>>>>>>>>
>>>>>>>> In a related experiment... I'm temporarily using some Maxwell "D-cell"
>>>>>>>> series caps to power the buoy flasher that got 6 months of use from
>>>>>>>> 3-AA alkaline cells, switching to a solar charged, 175 F, 3 V system
>>>>>>>> (using caps that cost $15 each). That system is flashing the strobe,
>>>>>>>> for 8 days on the charge it can get in one day. (cover the solar
>>>>>>>> cells with aluminum foil and wait till it dies).
>>>>>>>>
>>>>>>>> So a pair of the $1.29 50 F caps should easily last a day, or perhaps
>>>>>>>> just use one 50 F and go with 2.5V. (specs on the controller that I'm
>>>>>>>> using says it works down to 2.2V, and it seems to recover and start
>>>>>>>> running it's program from the beginning when the voltage gets to about
>>>>>>>> 2V)
>>>>>>>>
>>>>>>>> The buoy that I'm illuminating belongs to the city.. So I have to keep
>>>>>>>> the cost low in case they discover that I've modified the buoy and
>>>>>>>> decide to remove my strobe, or vandals (or Visigoths) make it to that
>>>>>>>> end of the lake and steal or destroy it...
>>>>>>>>
>>>>>>>> It's become a "thing" to tweak the buoy with something different each
>>>>>>>> year. I go kayaking at 3:30 AM to avoid the summer heat, but it's a
>>>>>>>> challenge to find ways to see where I'm going in the dark on a lake
>>>>>>>> that's 2 miles long.
>>>>>>>>
>>>>>>>> Radio beacon? or perhaps a super strobe that I can trigger from 2
>>>>>>>> miles away?
>>>>>>>
>>>>>>> Tritium light?
>>>>>>>
>>>>>>> Strontium aluminate paint?
>>>>>>>
>>>>>>> Both would be fairly short range visibility. For longer range, why not
>>>>>>> use GPS?
>>>>>>
>>>>>> Tried that too. Got a Magellan "waterproof" little hand-held thingee.
>>>>>> Cost a small fortune and wasn't waterproof enough to take dunking in
>>>>>> water. Since they stopped the extended warranty plan, I stopped
>>>>>> taking it kayaking. It was hard to read too...
>>>>>>
>>>>>> The nice thing about it was when I was on a new creek, I could see my
>>>>>> progress.
>>>>>
>>>>> There are some cool cmos-sensor night vision cams around these days,
>>>>> not expensive. We use one to film wildlife in the back yard at night,
>>>>> skunks and cats and raccoons and things. But they are not as sensitive
>>>>> as a real microchannel multiplier, and mostly not waterpoof.
>>>>
>>>> I'd love to have a small light waterproof camera to attach to my kite
>>>> when kite-yaking. Daylight is good enough for that, I only used the
>>>> kite twice in the dark and hundreds of times in daylight. Small and
>>>> lightweight are easy enough but waterproof is a whole 'nother thing.
>>>
>>> I have a Fuji XP-something I bought at Costco. I saw the other day they
>>> have a similar model. I haven't tested its waterproof qualities, but it
>>> is rated for pretty significant immersion.
>>
>> Individually, all the problems are solvable, together it is a
>> different story.
>>
>> The problems
>>
>> I need days with wind in the 8-16 mph range from the NE or SW.
>> Preferably steady with minimum gusting and within a range of arc of
>> ~30 degrees downwind. (that's just to test a new idea)
>>
>> Then there's the matter of pointing the camera without a lot of extra
>> lines and stuff to fool with because launching a kite from a sitting
>> position is tricky enough with three bridle lines, tow line, and four
>> drogue lines.
>>
>> It helps if the kite goes up the first try, because launching a wet
>> kite is harder. (assuming things aren't so twisted and knotted that
>> it still seems possible)
>>
>> Then the boat has to be traveling slower than the wind or the kite may
>> go in the drink and the boat drifts over it. That takes rafting to a
>> buoy or structure, or adding more lines with a sea anchor. The kite
>> sinks and will fly upside down in water too - so there's an extra
>> float attached to the drogue to deal with that.
>>
>> And miracle of miracles it all comes together for a new try - only to
>> discover that there's enough moisture inside the camera housing to
>> create condensate when the top half gets heated by the sun, and the
>> bottom where the lens is, is covered with water droplets.
>>
>> Just launching and flying a kite from a kayak is a challenge. I've
>> made every mistake in the book (if there were a book) and adapted and
>> created, and managed to get it to work when the wind cooperates. Even
>> on the best of days there will be times when I'm busier than the
>> proverbial "one-armed paper hanger."
>>
>> This is a lake with trees around it creating their own brand of
>> turbulence, wind eddies, down drafts, and shielding. Landing the kite
>> can be as challenging as launching, steering the boat so I don't
>> parallel the waves and capsize, pulling in line, keeping the paddles
>> from hitting the water while winding in line, worrying about getting
>> it all together before the kite drifts over a road or power line. The
>> kite has 300 lb line on it and it takes both arms just to pull in one
>> wrap around the winder some days. (I fly 4 kites depending on
>> conditions from a tiny one to a mammoth one)
>>
>> It can be exhilarating when the boat is flying along, but it's scary
>> too. I've only capsized three times and all three times I was using a
>> kite... The boat is pulling you along while you tread water trying to
>> get the kite line in. When the water temp is 40, that adds a whole
>> new dimension to the problem - the initial shock is bad, but after
>> awhile a kind of lassitude takes over and putting on the life jacket
>> just seems like too much hassle. "stay safe, have fun, don't get
>> caught"
>>
>> If it were easy, where would fun be in that?
>
>You don't wear a life vest?
No, too restrictive. A mini-vest with CO2 cartridge might be a good
idea, especially in the intra coastal water way or around the inlets.
No trees so it's excellent for a kite, but the river traffic is a
hassle.