Wikipedia:Reference desk/Archives/Computing/2016 August 17

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August 17[edit]

Setting up email on a Galaxy S5[edit]

I want to connect the phone to a Yahoo account. I've had trouble with the Yahoo account (too many people trying to adjust it), but now it is correct. Two devices, a Dell all-in-one and a Lenovo MIIX, can access the account okay.

I'm looking at the Samsung instructions here. However, when I enter the correct email address and password, I get "Unable to set up account, authentication failed."

I'm frustrated. Why would it work with two devices but not another? Can you help? --Halcatalyst (talk) 02:02, 17 August 2016 (UTC)[reply]

I have windows 10, why cant i store files larger than 4GB?[edit]

I have windows 10, why cant i store files larger than 4GB on my C: drive? — Preceding unsigned comment added by 76.24.101.161 (talk) 14:49, 17 August 2016 (UTC)[reply]

Check the volume type. Open the Properties dialog for the drive and check what it says against "File system". If it's NTFS, you should be able to store files of up to 16TB. If it's FAT32, then 4GB is the maximum possible file size. This link mentions a CONVERT command that will allow you to change the format of the disk, but I'll let someone who knows what they're talking about to suggest how to use it. Rojomoke (talk) 15:49, 17 August 2016 (UTC)[reply]
There's something fairly weird here. By C drive, do you mean the drive with Windows on it? If so, it's very weird that this would be FAT formatted. AFAIK, Microsoft hasn't even supported installing Windows on a FAT drive beginning with Vista [1] [2] (not surprising since they began to symbolic links etc even though these often weren't essential). I guess it's possible this changed with Windows 8 given the attempt to get Windows on tablets etc, but I doubt it. It may be possible to run Windows on a FAT drive [3], but still if your Windows drive is really FAT this is a very unusual config. Did you install Windows yourself or what? If your system/Windows drive is really FAT I think you should establish why before doing anything. Nil Einne (talk) 15:22, 18 August 2016 (UTC)[reply]
Do you actually have 4GB available on C: drive, or is that drive nearly filled up? Akld guy (talk) 20:11, 18 August 2016 (UTC)[reply]

Radio alarum gaining[edit]

I have a Morphy Richards electronic radio alarum clock, model 28009, which gains consistently a few minutes a week. Out of curiosity I have investigated the innards, and it is driven by an SC8560 digital-alarum-clock-on-a-chip [4] - it looks something like this inside. This chip takes the mains frequency (50 Hz) on pin 25 and drives the clock from that. The mains frequency in the UK is incredibly accurate in the long term - it is not allowed to "drift".

I'm wondering how the clock is gaining, and if there's any fix I can implement. There are a couple of trimmable components near the chip, they look like chokes.

All the best: Rich Farmbrough, 20:29, 17 August 2016 (UTC).[reply]

Is the clock plugged into an outlet that is shared by an appliance that draws a large current at startup, such as a fridge/freezer, power saw, or stove? I'm thinking that transients at startup may be causing extra pulses. Akld guy (talk) 22:04, 17 August 2016 (UTC)[reply]
No, there's a lamp and a laptop (usually on charge) and a few chargers. The only interesting sidelight is that it seemed to not gain as much when I plugged in another radio alarum. I was thinking there could be a sycnhronization effect, but I suppsoe it's possible that it soaked up some noise. All the best: Rich Farmbrough, 23:08, 17 August 2016 (UTC).[reply]
(ec) Most alarm clock-radios I've owned have a compartment for a 9V battery for backup in case of a power failure. When the power comes back on the time is spot on. That tells me it is not reliant at all on the mains frequency to provide a timing signal. Rather, it probably uses a 555_timer_IC or a variant thereof. I just don't see why one would use the mains frequency for timing when such very stable and cheap timers are available. The clock and radio circuits are DC. Any mains frequency timing making it through the step-down transformer is going to be bad quality. Anybody care to comment please? 196.213.35.146 (talk) 11:57, 19 August 2016 (UTC)[reply]
You may well be correct about the timing chip (no doubt someone will know whether or not the design relies on the mains frequency), but
A conventional (wire-wound) transformer, even of the very cheapest design, retains the exact properties of the mains frequency which, as Rich says, has a long-term accuracy that far exceeds cheap timer chips. Dbfirs 14:07, 19 August 2016 (UTC)[reply]
My experience is somewhat different from the IP. I've found the the battery backups tend to be inaccurate after a few hours. See also [5]. (Note one point not well discussed there but mentioned by one respondent and of relevance to the suggestion of it being a coincidence based on when the time came back, all radio alarm clocks I've owned have made the time flash when it hasn't been set after being first turned on.) In addition, most radio alarm clocks I've owned have had a 50/60 hz frequency selection button and I don't see why you'd bother with one unless the clock is influenced by the frequency. AFAIK, there's generally little relevance of the utility frequency to the radio portion. Admittedly my experience is probably over 15 years old however I'm not sure how old the OP's clock is. Nil Einne (talk) 14:25, 19 August 2016 (UTC)[reply]
The user manual for that model specifically states that timekeeping will be inaccurate when running on the 9v battery, so clearly mains frequency synchronicity is the principal timekeeping method. I suppose it's just possible that the Switched-mode power supply of the laptop (or the dimmer of a lamp) is introducing distortions in the waveform that the clock is interpreting as extra cycles, but this seems unlikely to me. Dbfirs 21:04, 19 August 2016 (UTC)[reply]
Yes, that has been my experience. They are stunningly inaccurate on battery power, like off a minute every 10 minutes. Seems like it must be somehow dependent on the voltage of the battery to be so incredibly inaccurate. I never understood why they would use such a system, as a quartz crystal is cheap and accurate, but perhaps not quite cheap enough. StuRat (talk) 21:21, 19 August 2016 (UTC)[reply]
This system has one other chip a CD7613CP single chip AM/FM radio. There is no 555 or crystal. The clock must rely on a simple discrete component timer when on battery power. The single-chip alarum clock includes "built in battery-backup CR oscillator",[6] although for the period of observation, no battery was used. All the best: Rich Farmbrough, 10:56, 21 August 2016 (UTC).[reply]
BTW, why do you use the archaic "alarum" instead of the modern "alarm" ? StuRat (talk) 21:22, 19 August 2016 (UTC)[reply]
Use it or loose it. All the best: Rich Farmbrough, 10:56, 21 August 2016 (UTC).[reply]
  • I'm going to try this on a surge protected power outlet. All the best: Rich Farmbrough, 16:53, 22 August 2016 (UTC).[reply]
    • On the surge protected outlet it reverted to much greater gains. When it was sharing with the replacement clock (which gains very slightly) it was only moderately awful. So I have binned it. All the best: Rich Farmbrough, 23:01, 28 August 2016 (UTC).[reply]