Zero volts is induced into the head at zero speed, so if it slows down and reverses direction, it will lose track. Hard drive S/N ratios are not very generous as-is, and will degrade as the disk slows down.
Doubt it.
John
I'm crushed by your retarded attempt at playground bully retarded remarks. You almost made it.
Your entire, pathetic, cringing milksop hulk IS POO.
No, it will not. The track has direction specific bits laid onto it, and direction of rotation would ALWAYS be determinable.
You do not understand. Hard drives have things called "sector flags" and they are hard magnetized onto the platter, and cannot be erased. They tell the electronics where the platter is and the signals popping off the head as it traverses them is greater than the signals popping of the data areas. As the disk slows down, the signal would be no different than that of a floppy performing the same action. So, the hard sector flags are what get read, regardless of rotational speed or direction.
That is what I said.
You are too stupid to have any grasp where you could raise doubt in a real scientist, however. Nice try, shitbot. What shit spew is going to come out of you next?
Yes. Another alias for jack snipped-for-privacy@cox.net
Because you need d(phi)/d(t) to make a signal in a pick-up coil, John is correct. Are the heads using something else like, say, a hall-effect device to read that stuff these days?
most
I had a newly hired coworker put on rubber gloves before probing a
3.3V supply circuit he had just designed. When I asked him if he was worried about daming the compoents, he told me he was worried he'd be shocked.Mark DeArman
ing the
That's Jamie relying on his fertile imagination again. I don't use a spell checker when I post here - the advantages of posting through groups.google.com outweight Thunderbird's spell checking.
I have been known to go to a dictionary to check out a spelling checker's suggestion - their vocabularies are slightly smaller than mine - but Jamie shoudl hae been able to recognise that most of my spelling errors are the usual omissions and transpostions that you find in most typos, and which spelling checkers catch pretty effectively.
And Jamie is scarcely in a position to complain about anybody ignoring a valid error. He makes errors pretty much non-stop, and I've yet to see him acknowledge that he has ever got anything wrong. I do get things wrong from time to time - not very often and far less often than Jamie lies to think - and it happens that you can find one of my errors earlier in this thread, followed by my grateful acknowledgement of the correction.
-- Bill Sloman, Nijmegen
most
an
unfounded.
the
I suppose he'd never handled a 9-volt battery with his bare hands.
John
AKA AlwaysWrong.
John
The GMR heads are magneto-resistive, but I doubt you could get anything usable out of them at near zero speed. And he hasn't specified how he'd keep the head a few micro-inches above the platter, or how he'd servo for track alignment.
Optical with interpolation works well at millions of counts per revolution. There were (are?) inductosyn rotary encoders, but they are basically transformers.
Yup, still made:
John
an
lom=3D
al
t.
So you tell me. I'm not minded to believe you.
-- Bill Sloman, Nijmegen
That's Jamie relying on his fertile imagination again. I don't use a spell checker when I post here - the advantages of posting through groups.google.com outweight Thunderbird's spell ^^^^^^^^^ checking.
I have been known to go to a dictionary to check out a spelling checker's suggestion - their vocabularies are slightly smaller than mine - but Jamie shoudl hae been able to recognise that most of my ^^^^^^ ^^^ spelling errors are the usual omissions and transpostions that you ^^^^^^^^^^^^^ find in most typos, and which spelling checkers catch pretty effectively.
Not counting recognise vs recognize, you only had 5 misspellings in this one, Mr. Ph.D.
It doesn't run, fatal error on the missing value for R3. Also, no .tran statement.
Sad to see you attempt to cast doubt on his statement. Either you've read with bias the many thank you posts he's received, or haven't seen them. It's a fact: JF has received many thanks over the years for the skilled technical assistance he has provided on these newsgroups.
Ed
Wat is minded Mr. Slowman?
Awwww, John, he's crushed! Doesn't that break your heart?
Wow, John. You are starting to see the kind of EE graduate i see rather daily. Of course my CPE, paying near bottom of the barrel wages, gets a lot of such. Kind of funny how in general, but not quite always in specific, you get what you pay for.
?-)
This is a complete disaster. Your schematic beginning at Version 4 and ending at SYMATTR Value 2V (above) is a circuit but with no value for R3 as Ed pointed out. Worse, the transistors are the default ones when initially placed on the schematic because there is no reference to the devices to your BFR90 or 92A on the schematic. You have a DC source that does nothing transient-wise or AC-wise.
It runs in LTSpice if simulated with the DC Operating Point. The out put is 1.2V if I use a 1k for R3.
Try using your spell checker. It's smarter.
That word is spelled differently 'over there'. Not a surprise that you did not recognize that fact.
most
an
absolute
unfounded.
the
participating
Or put his tongue on the terminals to 'taste' electricity? ;)
Grant.
Gotta let him use the Queen's English, born in .au? I've got to put up with a heavily bouncing keyboard on this lappy. Drives me mad in Agent, 'cos it doesn't run a spellchecker in the background. Three year old lappy's got dual cores, should be handle that? Grrr! I digress, this thread's been dragging on too long. Agent is showing its age, lack of development?
Grant.
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