Instruction: Analyze a question and its supporting document. Predicting answerability based on the information provided in the document. Output yes if the document contains relevant information to answer the question, otherwise output no.

Input:
Question: How many hours of sunlight does it need to charge up?
Document: This is incorrect. If you think the battery is not getting fully charged, then you should set the switch to "ON" during the day, and then "OFF" just before dusk so that the battery does not discharge. Do this for a few days, and even in a location without much direct sunlight, the battery should eventually fully charge.Once I got the mobile working, it works perfectly and is absolutely gorgeous and captivating.
When the lights are on at night, the total current is only 25 mA. Thus, when fully charged, the birds should stay lit for more than 24 hours, which is obviously longer than any night, except north of the arctic circle.I have verified these theoretical calculations in actual practice: the birds did indeed stay on all night after a full day outdoors in the sun.One note: the unit does NOT charge if you set the switch to off.
However, if you hang the birds INDOORS next to a double-pane window in full sun, and orient the solar collector to face the sun, it takes twelve hours to provide enough charge to run the birds all night. If you instead simply hang the mobile so that the solar collector is facing directly upwards, rather than facing the sun, this triples the time required to charge compared to the outdoor figure.
To my surprise they are much brighter than I expected. They also stay on all night with the single daylight charge. Even looks good during the day.
These lights are very beautiful. I have them in my back yard and they light up beautifully at night. Once fully charged you get 6-8 hours of light from them.
I didn't know they made AA batteries with this little capacity; most of them are around 2,000 mAh. If you take out the three screws under the solar cell, you can easily replace the battery (it is in a holder). However, there isn't any real reason to replace it with a super-high capacity AA rechargeable. Why? Well I measured the amount of current used to charge it, and it is only about 75 mA in full Northern California mid-day winter daylight.
The birds themselves are made of sturdy acrylic plastic and seem to be nicely made. [update]We got this mobile in the dead of winter, and after I got it working, I tried to figure out why it only stayed on for a few hours in the evening. I did some measurements with a little hobby solar cell and figured out the answers.
I received this as a gift, and initially it didn't work very well. It was absolutely beautiful and captivating, but would only run for a few hours after dusk. After a few days, it wouldn't run for more than a few minutes.I opened it up, and being an electrical engineer, immediately found the problem: bad solder joints. The circuit board that controls the charging was just dangling in space, not mounted to anything, and two of the wires were loose in the circuit board.
Oh yes, if the indoor location doesn't receive direct sun, even if it is near the window, then you only get about 1/20 the amount of energy that you get outdoors, and the birds won't light for more than a few minutes.I have verified these calculations and have found that, when hung indoors next to a southern facing, double-pane window with the solar collector in a horizontal position, the birds stay lit for only 2-4 hours.
Very unique when this item lights up. Looks just as great during the day....love this one and may buy a coupke more for Christmas gifts as everyone who sees it wants to know where I got it.
Answer: yes