[time-nuts] time-nuts Digest, Vol 58, Issue 51

Robert Atkinson robert8rpi at yahoo.co.uk
Fri May 22 06:39:52 UTC 2009


Hi Paul,
Glad I didn't say no aircraft clocks use a 60Hz timebase! I wonder if they used a commercial (non-aircraft) movement? The design seems to break the normal aircraft design premise that a single failure should not cause the loss of more than one duplicated system. Unless the clocks have some kind of back-up osvillator loss the the clock source would kill all three clocks. In the UK regulations, clocks sort of slip through a gap. You have to carry one, but it doesn't HAVE to be specifically approved for aircraft use. We used to gent them repaired by a local clockmaker.

Regards,
Robert. 

--- On Fri, 22/5/09, Paul Nelson <drhydro at qwest.net> wrote:

> From: Paul Nelson <drhydro at qwest.net>
> Subject: Re: time-nuts Digest, Vol 58, Issue 51
> To: time-nuts at febo.com, "Robert Atkinson" <robert8rpi at yahoo.co.uk>, "Charles Rushing" <crushin2000 at austin.rr.com>, "Bill Hawkins" <bill at iaxs.net>
> Date: Friday, 22 May, 2009, 5:28 AM
> Well, I found some stuff on this
> clock... from a few handwritten notes I made several years
> ago, there exist both types; those that have an internal
> timebase, and those that require an external timebase. The
> clock that I can put my hands on right now is an A15586; I
> have a couple more. The timebase is an E13832-P1, and it
> consists of a TCXO with an output frequency of 983.040 Hz
> and a couple of chips (CD4013 and CD4020) which output a
> two-phase square wave signal at 60 Hz to drive the stepper
> motor inside the clock. Basic wiring is as follows- there
> are usually two connectors on the clock, one of which
> matches the connector on the timebase- a 12-pin circular
> connector, MS27034H12B12PN. The other, larger, connector is
> for the ARINC bus stuff.
> 
> I've had all of mine working with that timebase.
> 
> If your clock has an internal timebase, it should work
> simply by powering it with 24v on pins 3 and 4. I don't know
> which ones do and which ones don't- there's a whole bunch of
> variations.
> 
> Pin        Clock     
>                
>   Time base
> 1            5v
> lighting             
>       n/c
> 2            5v
> lighting             
>       n/c
> 3            +16to32v
> ----------->   +16to32v
> 4         
>    -16to32v ----------->   
> -16to32v
> 5            Case gnd
> ------------>   Case gnd
> 6            Ph 1 drive sig
> in --->    Ph 1 drive sig out- capt clock
> 7            Ph 2 drive sig
> in --->    Ph 2 drive sig out- capt clock
> 8               
>                
>                
>     Ph 1 drive sig out- F/O clock
> 9               
>                
>                
>     Ph 2 drive sig out- F/O clock
> 10               
>                
>                
>   Ph 1 drive sig out- F/E clock
> 11               
>                
>                
>   Ph 2 drive sig out- F/E clock
> 12               
>                
>                
>    spare
> 
> time-nuts-request at febo.com
> wrote:
> > 
> > Message: 2
> > Date: Thu, 21 May 2009 17:50:33 +0000 (GMT)
> > From: Robert Atkinson <robert8rpi at yahoo.co.uk>
> > Subject: Re: [time-nuts] 747 Chronometer
> > To: crushin at ieee.org,
> Discussion of precise time and frequency
> >     measurement   
> <time-nuts at febo.com>
> > Message-ID: <240600.56920.qm at web27104.mail.ukl.yahoo.com>
> > Content-Type: text/plain; charset=iso-8859-1
> > 
> > 
> > Hi Charles,
> > I had a dig, but could only find info on the current
> clocks that receive time info on an ARINC 429 serial bus,
> and an earlier hybrid LCD / mechanical model that needs an
> external 1PPS (I'd like one of those).
> > I've never seen an aircraft clock that needed an
> external 60Hz signal. Unfortunatly Hayden have been bought
> up and no longer list instruments. Keep Googling!
> > 
> > Robert G8RPI
> > 
> > --- On Thu, 21/5/09, Charles Rushing <crushin2000 at austin.rr.com>
> wrote:
> > 
> >   
> >> From: Charles Rushing <crushin2000 at austin.rr.com>
> >> Subject: [time-nuts] 747 Chronometer
> >> To: time-nuts at febo.com
> >> Date: Thursday, 21 May, 2009, 7:45 AM
> >> Greetings To All,
> >> 
> >>  
> >> Please accept my apologies in advance if this is
> >> off-topic.? I have just
> >> acquired an aircraft clock, which I've
> tentatively
> >> identified as coming from
> >> a Boeing 747.? It's way cool looking and would
> make a
> >> perfect dust collector
> >> in my ham shack if I could only power it up.
> >> 
> >>  
> >> There is a multi-pin military-style twist-lock
> connector on
> >> the back, but no
> >> indication of what the pinout may be.? The unit
> is
> >> identified as:
> >> 
> >>  
> >> "CLOCK, 3" 24 HOUR GMT ELECTRONIC
> >> 
> >>  MFD BY A.W. HAYDON CO. PRODUCTS
> >> 
> >>  NO. AMER. PHILIPS CONTROLS CORP.
> >> 
> >>  Cheshire, Conn.
> >> 
> >>  MFR'S. PT. NO. A15551-P1"
> >> 
> >>  
> >> I've searched the Net for technical documentation,
> but
> >> could only find the
> >> reference to the 747.? Does anyone have any
> >> information about these clocks,
> >> or can someone point me in the right direction?
> >> 
> >>  
> >> Many thanks in advance.
> >> 
> >>  
> >> Chuck
> >> 
> >> WA5MUV
> >> 
> >>     
> 
> -- Paul Nelson W5GNF         
>     "When I go, I want to go quietly, in my
> Ames, Iowa             
>        sleep, like my grandfather-
> not Senior Engineer (Retired)      screaming,
> like his passengers."
> Sauer-Danfoss Company
> (DrHydro at qwest.net)
>                
>               "More hay,
> Trigger?"
> ex-Cessna 140 N77149 (sigh)   "No thanks,
> Roy, I'm stuffed."
> 
> 


      



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