A mechanical phase locked loop!

On 08/06/17 17:34, Gareth's Downstairs Computer wrote:


Perhaps you are right, but does that matter ?. Might not all have the tech ability of the past, but just as keen on operating and the social aspects of the hobby. We can't all be tech experts, but there are still plenty of deep tech areas for those interested.
Seems a bit of an elitist attitude really, speaking as one who built his first one valve set at 11 and always more interested in the tech side than operating...
Chris
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On 06/08/2017 19:58, Chris wrote:

Elitism, yes, and something to be jealously guarded.
AIUI, there are already countries where only commercially available rigs may be used, and by flooding this country with technical numbskulls risks the powers-that-would-be perceiving we all as operators only.
Amateur radio is primarily a technical pursuit with operation being a trivially simple follow-on; so trivially simple, in fact, that it is a nonsense to examine based upon operating. The 5-year-old with her smartphone does not have to pass an exam on her operating capability!
As to your last comment, Yes, more technician than operative, I still maintain a logbook, with all test and CQ calls logged, and yet after 47 years I'm only just half way through my 2nd log book.
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On 06/08/2017 20:18, Gareth's Downstairs Computer wrote:

If operating is so trivially simple why couldn't you tune the PA in the radio you bought? Even CBers can do that.
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Do you need to trade silly (and, yes, typically junior school stuff) abuse rehearsed from interminable local arguments all over the Internet? Why not keep this childish repetitive stuff for ukra where it "belongs"? You *are* an adult, aren't you? Gareth's silly comments are quite obviously silly comments without you clutttering the place up arguing with him about it. If you think his comments about operating being too easy and of no interest are inaccurate, why not say so, at least it will soon be obvious he is in a minority of one? I for instance have very little interest in operating but agree that it is an essential and worthy part of the hobby (and not so easy as Gareth thinks) so why not stick to the actual issue when discussing it internationally and outside of the AR groups?
--

Roger Hayter

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Jeff wrote on 8/6/2017 6:38 AM:

...and that is a measurement. It determines if the relative phase is plus or minus, a binary measurement. This is exactly the same as the measurement taken by a 1 bit ADC. Even though it is one bit it is still a measurement.

Totally wrong. The phase adjustment varies from a constant about to ZERO! Again it is a binary adjustment.
If there was a three level range of measurement and adjustment +, 0, -, would that be enough to constitute a measurement and adjustment so it becomes a PLL? If not, how many bits are required? If any number of bits can't do it are digital PLLs not PLLs?
--

Rick C

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https://en.wikipedia.org/wiki/Shortt%E2%80%93Synchronome_clock#Hit_and_miss_synchronizer
"This feedback loop functioned as an electromechanical version of a phase-locked loop..."
--
Jim Pennino

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..and of course everything on Wikki is correct!!!
Jeff
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The usual cry of those who have not bothered to do any research on a subject and are shown a Wiki article that contradicts their position is that Wiki can be edited by anybody.
Wiki is more correct than most of the babble on USENET and the Wiki article has 18 external references to back it up.
Where is your annotated list of references?
Here's another site that says the same thing:
http://www.meccanotec.com/shortt.html
"The slave is kept in synchrony with the master in a phase locked loop."
--
Jim Pennino

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On 8/3/2017 3:05 PM, Chris wrote:

In this case I have to (surprise!) agree with Rickman. A phase locked loop is never in lockstep with the reference - there is always a bit of drift in the oscillator.
It's no different than driving down a highway. You can aim your car straight down the road - but you need to continually make small adjustments to account for things like the road and the wind.
The Shortt clock is not that much different, except that it purposely runs at a slightly lower frequency than the reference, and the frequency at which the comparison occurs is much lower.
But the result is the same - a signal that is accurate due to compensation based on the instantaneous phase at specific times.
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