Ems2s Msf Reciever Module

[wombweller]

Hi all

Recently I have be putting together a digital clock circuit nothing to difficult just using a bunch of 4026b decade counter / drivers to 6 seven segment displays showing 24hr's

I have this running fine under simulation using Livewire so now it's just a case of putting the circuit on board.

While playing around with this circuit I was thinking about timebase and the many ways to get to 1Hz but then I wondered about the MSF time signal from NPL. :
https://resource.npl.co.uk/docs/networks/time/meeting3/martin.pdf

This signal can be picked up by the "EMS2S MSF RECEIVER MODULE" made by Galleon:
**broken link removed**

Now I was wondering if I could integrate this module within my clock circuit and decode the MSF time signal .I searched the net for info and did not really find much that dealt with digital clock circuits that wasn't using a PIC.

My big question is- has anyone on the Forum used the "EM25S" in a clock circuit such as I am wanting to do.?
Also would anyone be able to advise me if this is really doable through the circuit I have built.?
It wouldn't really matter if I had to alter the circuit to accommodate for this.

Any advise would be a great help I also want to try and get my head around the time signal and how to manipulate it even if it doesn't end up in the clock

Regards Mark

 

[blueroomelectronics]

You'll need a microcontroller to decode your Ems2s reciever data.
Synchronizing time with DCF77 and MSF60

 

[wombweller]

You'll need a microcontroller to decode your Ems2s reciever data.
Synchronizing time with DCF77 and MSF60

Hi and thanks for the link, I will read through that.

So are you saying there is no possibility at all to use the module without the aid of a PIC ?

Mark

 

[picasm]

The MSF signal does provide accurate 1 second pulses, the pulse goes low at the start of each second for a duration that varies but is at least 100ms low and 700ms high before the next low pulse (except for second 00 which is just 500ms low then 500ms high.
https://www.electro-tech-online.com/custompdfs/2008/06/MSF_Time_Date_Code.pdf

You could just use it as a 1 second timebase and not bother decoding the data.
Although, you may find there are cheaper alternative solutions.
eg. use the 1 second pulse from an old quartz clock mech or perhaps the very accurate 1 second pulse available from some older GPS modules.

 

[wombweller]

The MSF signal does provide accurate 1 second pulses, the pulse goes low at the start of each second for a duration that varies but is at least 100ms low and 700ms high before the next low pulse (except for second 00 which is just 500ms low then 500ms high.
https://www.electro-tech-online.com/custompdfs/2008/06/MSF_Time_Date_Code-1.pdf

You could just use it as a 1 second timebase and not bother decoding the data.
Although, you may find there are cheaper alternative solutions.
eg. use the 1 second pulse from an old quartz clock mech or perhaps the very accurate 1 second pulse available from some older GPS modules.

Hi and thanks!!

Again the outcome seems to be that it is just not possible do what I was looking for!!

I was somewhat hoping that the decoded msf time signal way would work but I'm not surprised that it won't just a little saddened.

Never mind all is not lost.I have a number of options:

1) I learn PIC programming
2)Use the msf 1 sec pulse as the time base to my clock
3)GPS.
4)The many other options available to generate a 1hz signal.

I'm not too sure that by using the msf 1 sec pulse purely for that reason alone is worth the effort and cost, please see attachment.

I do have a PIC programmer and can flash PIC's but I have not yet got my head fully around the programming "e" for that
I have looked for seven segment clock via PIC tutorials but haven't found one yet.
If anyone knows of one perhaps they could point it out to me.

I would like to hear about GPS. can you please elaborate?

Regards Mark

 

[picasm]

The modules in that price list that you attached are quite high considering the same module is only about 11 Euro from a German web site:
HKW-Elektronik GmbH | A Passion to Precision.

Another way to get an MSF receiver is to buy a complete MSF clock (from ebay perhaps), but you then have to find the data connection by probing the pcb tracks around the resin blob chip.

GPS can be an option if you obtain an old gps module with a serial data interface.
Some of them also have an output pin with a very precise 1 second pulse (when they have a good signal)
You would need to find a data sheet for any prospective module to check that it has the 1 second pulse option.
You would also need a matching gps antenna ideally externally mounted or on a window ledge with a clear sky view may be just sufficient.

 

[blueroomelectronics]

You'll need to decode the GPS NMEA sentences. Swordfish BASIC has a NMEA module that makes it easy to do. Again you need a microcontroller. Your entire clock would probably take only a PIC and a few transistors and an extra IC or two.
**broken link removed**
The Dragonfly, clock source code can be found in the Dragonfly assembly manual.

 

[tunedwolf]

It was commonplace at one time to build and use a simple receiver to use the carrier frequency of a radio station, one that used an atomic source, to drive a divide/pll circuit to obtain a very accurate timebase. The accuracy obtained is as close as you will get without using an atomic source.

rgds

 

[ericgibbs]

hi,
As the high MSF and EMS are expensive in the UK, I decided to see if I could pick up the 1 second pulse
from a MSF wall clock, dial type with hands, value about £8GBP

I discovered on the back of the MSF module a small sticky label.

Peeling off the label revealed a 2 pin male connector, 0.1inch pitch.

Scoping the pins gave a 1second regular pulse, about 1.5V in amplitude.

After I had removed and replaced the battery, the clock started to adjust for the correct time.
During this time the pulse rate increased until the clock was correct, then a 1sec regular pulse.

This a very low cost way to get a MSF 1 second sync signal.

EDIT:
Checked a second MSF clock from another supplier, that also has the 2 pin male connector.
This must be a factory test feature, so its probably on most clocks.

 

[ericgibbs]

hi,
The wall clocks that always have the connector are the 'KLIK' model.
Available from CPC or Farnell.

Checking the latest prices show that the current lowest price is about £12GBP, thats inflation over the past 4 years!!.

When buying a clock for this MSF feature, check the inner module of the clock for the connector.

 

[wombweller]

hi,
As the high MSF and EMS are expensive in the UK, I decided to see if I could pick up the 1 second pulse
from a MSF wall clock, dial type with hands, value about £8GBP

I discovered on the back of the MSF module a small sticky label.

Peeling off the label revealed a 2 pin male connector, 0.1inch pitch.

Scoping the pins gave a 1second regular pulse, about 1.5V in amplitude.

After I had removed and replaced the battery, the clock started to adjust for the correct time.
During this time the pulse rate increased until the clock was correct, then a 1sec regular pulse.

This a very low cost way to get a MSF 1 second sync signal.

EDIT:
Checked a second MSF clock from another supplier, that also has the 2 pin male connector.
This must be a factory test feature, so its probably on most clocks.

Hi Eric

You're not kidding they are very expensive even when relative to the work you intend for it,Even more so if you only want it for the 1 sec timebase like I'm thinking.

I think that to add just a but of a touch to my basic clock I could purchase a secondhand radio clock from Ebay maybe and rob out the MSF. reciever and tap in to the signal.

One thought before I do this, you say the 1 sec signal you tested speeds up to set the time, I woudn't have that setting function as I don't have a PIC.that remebers where the time on my clock is at but won't this effect my read out by speeding up the timebase????

Regards Mark

 

[wombweller]

hi,
The wall clocks that always have the connector are the 'KLIK' model.
Available from CPC or Farnell.

Checking the latest prices show that the current lowest price is about £12GBP, thats inflation over the past 4 years!!.

When buying a clock for this MSF feature, check the inner module of the clock for the connector.

Looking like a good possibility there Eric.


Cheers Mark

 

[picasm]

One thought before I do this, you say the 1 sec signal you tested speeds up to set the time, I woudn't have that setting function as I don't have a PIC.that remebers where the time on my clock is at but won't this effect my read out by speeding up the timebase????

I have an MSF wall clock. When a new battery is fitted, it pulses the hands round very rapidly until it reaches a reference position, then it waits for a complete timecode and pulses the hands until it shows the correct time.

Also, it may pulse rapidly during the summer/winter time hour changes and finally, the MSF signal does have scheduled downtimes several times a year for maintenance.
During that period of no signal, the clock would use it's internal timebase and may have to pulse the hands to correct the time when the signal is restored.
(The scheduled downtimes are shown on the NPL web site)
**broken link removed**

 

[wombweller]

I have an MSF wall clock. When a new battery is fitted, it pulses the hands round very rapidly until it reaches a reference position, then it waits for a complete timecode and pulses the hands until it shows the correct time.

Also, it may pulse rapidly during the summer/winter time hour changes and finally, the MSF signal does have scheduled downtimes several times a year for maintenance.
During that period of no signal, the clock would use it's internal timebase and may have to pulse the hands to correct the time when the signal is restored.
(The scheduled downtimes are shown on the NPL web site)
**broken link removed**

Thanks picasm

This is my point, because the circuit I have does not have a pic. thus will not adjust for down time or winter/sunner time then using this signal may not be appropriate for this timebase ??

I was somewhat hopping that a solution for time setting would come up with these chats for a CMOS LOGIC circuit using differant IC's but now seems obvius that the only way is a PIC.

Does anyone know of a PIC project for such an application on the net?

Regards Mark