Roberts Radio Alarm - clock not setting
 

Hi
I picked up a nice Roberts radio alarm at a car boot. It has a feature
whereby it automatically sets the time on it's own via the Rugby[1] time
signal.
However, this feature isn't working & a scan through MW has little to no
reception.
I deduce from this that there's no reception of the 60kHz signal getting
through.
I'm not averse to taking it apart & having a look inside, I'm guessing
an issue with the ferrite rod aerial inside? Anything else I should be
looking for in particular?

Cheers

[1] I know it's moved from Rugby now.

Roberts Radio Alarm - clock not setting
 

On 29/06/2020 12:10, Chris Hogg wrote:
Are you sure it gets its time signal from NPL Althorne? I ask because
I have a Roberts radio, much more recent than yours by the sound of
it, that gets its timing from the DAB signal. If the DAB signal is not
available, you have to set the time manually and hope it keeps
correct.

Yes, it's pre DAB. I downloaded the manual that confirms it gets the MSF
signal.

If you're certain yours gets its signal from Althorne, then try just
moving the radio to a different place in the house, as in the past

I did go from down to upstairs but will try other locations.

Does your radio have a telescopic aerial?

It's a loose wire affair, common on clock radios. It gets FM on this OK.

Is 60kHz medium wave? I'm pretty rusty on that sort of
thing.

Not sure, maybe it has another antenna for the MSF?

Roberts Radio Alarm - clock not setting
 

On Mon, 29 Jun 2020 12:36:47 +0100, CD wrote:

Is 60kHz medium wave? I'm pretty rusty on that sort of thing.

It's rather long wave, technically.


Not sure, maybe it has another antenna for the MSF?

Probably a ferrite rod. Look for broken ferrite, or just a broken wire
(if the former, then almost certainly the latter; probably if it's been
dropped).

For the avoidance of doubt, it's ANTHORN.

Pretty picture!

https://goo.gl/maps/8maKpEy9aNcvkAMs7



--
My posts are my copyright and if @diy_forums or Home Owners' Hub
wish to copy them they can pay me £1 a message.
Use the BIG mirror service in the UK: http://www.mirrorservice.org
*lightning surge protection* - a w_tom conductor

Roberts Radio Alarm - clock not setting
 

CD wrote:

Chris Hogg wrote:

If you're certain yours gets its signal from Althorne,

Anthorn BTW

It's a loose wire affair, common on clock radios. It gets FM on this OK.

Is 60kHz medium wave? I'm pretty rusty on that sort of
thing.

Not sure, maybe it has another antenna for the MSF?

A ferrite rod is usual on dedicated MSF receivers

Roberts Radio Alarm - clock not setting
 

On 29/06/2020 12:36, CD wrote:
On 29/06/2020 12:10, Chris Hogg wrote:
Are you sure it gets its time signal from NPL Althorne? I ask because
I have a Roberts radio, much more recent than yours by the sound of
it, that gets its timing from the DAB signal. If the DAB signal is not
available, you have to set the time manually and hope it keeps
correct.

Yes, it's pre DAB. I downloaded the manual that confirms it gets the MSF
signal.

If you're certain yours gets its signal from Althorne, then try just
moving the radio to a different place in the house, as in the past

I did go from down to upstairs but will try other locations.

Does your radio have a telescopic aerial?

It's a loose wire affair, common on clock radios. It gets FM on this OK.

Is 60kHz medium wave? I'm pretty rusty on that sort of
thing.

Not sure, maybe it has another antenna for the MSF?

MSF is typically a coil on a ferrite rod connected to a tiny module that
decodes it to a signal. There is usually a 60kHz xtal filter there too.

They can be quite directional in that era so try rotating it 15 degrees
at a time and leave it to settle. You only need to do a quarter turn.

It is longer than old Longwave 200kHz band - indeed one quick way to
make a Rugby receiver was to slug an existing longwave coil with roughly
2x the initial capacitance to bring its tuning frequency down to 60kHz.

--
Regards,
Martin Brown

Roberts Radio Alarm - clock not setting
 

On 29/06/2020 11:38, CD wrote:
Hi
I picked up a nice Roberts radio alarm at a car boot. It has a feature
whereby it automatically sets the time on it's own via the Rugby[1] time
signal.
However, this feature isn't working & a scan through MW has little to no
reception.
I deduce from this that there's no reception of the 60kHz signal getting
through.
I'm not averse to taking it apart & having a look inside, I'm guessing
an issue with the ferrite rod aerial inside? Anything else I should be
looking for in particular?

Cheers

[1] I know it's moved from Rugby now.

You could try it again in the evening as they often stop transmitting
for maintenance during the daytime in summer:
https://www.npl.co.uk/msf-signal

Though the lack of MW reception is odd.

--
Max Demian

Roberts Radio Alarm - clock not setting
 

CD wrote:
On 29/06/2020 12:10, Chris Hogg wrote:
Are you sure it gets its time signal from NPL Althorne? I ask because
I have a Roberts radio, much more recent than yours by the sound of
it, that gets its timing from the DAB signal. If the DAB signal is not
available, you have to set the time manually and hope it keeps
correct.

Yes, it's pre DAB. I downloaded the manual that confirms it gets the MSF
signal.

If you're certain yours gets its signal from Althorne, then try just
moving the radio to a different place in the house, as in the past

I did go from down to upstairs but will try other locations.

Does your radio have a telescopic aerial?

It's a loose wire affair, common on clock radios. It gets FM on this OK.

Is 60kHz medium wave? I'm pretty rusty on that sort of
thing.

Not sure, maybe it has another antenna for the MSF?

A 'loose wire' external aerial may work quite well on FM but will have
very little effect on MW or LW, it's the internal ferrite rod aerial
that will be used for those. The 60kHz time signal is right down the
low end of LW (well LF, it's below the broadcast band) so I think it
can only be using the ferrite rod for receiving this.

It's Anthorn not Althorne by the way.

--
Chris Green
·

Roberts Radio Alarm - clock not setting
 

On 29/06/2020 12:36, CD wrote:
On 29/06/2020 12:10, Chris Hogg wrote:
Are you sure it gets its time signal from NPL Althorne? I ask because
I have a Roberts radio, much more recent than yours by the sound of
it, that gets its timing from the DAB signal. If the DAB signal is not
available, you have to set the time manually and hope it keeps
correct.

Yes, it's pre DAB. I downloaded the manual that confirms it gets the MSF
signal.

If you're certain yours gets its signal from Althorne, then try just
moving the radio to a different place in the house, as in the past

I did go from down to upstairs but will try other locations.

Does your radio have a telescopic aerial?

It's a loose wire affair, common on clock radios. It gets FM on this OK.

Is 60kHz medium wave? I'm pretty rusty on that sort of
thing.

Not sure, maybe it has another antenna for the MSF?



I have a Roberts radio alarm clock that uses the MSF signal. On the
back it has a detachable aerial for the MSF which can be positioned for
the best signal.

Whilst I like the idea of the clock being accurate, I have never thought
that it worked very well. Some time ago whilst walking in Luxembourg I
saw a similar radio in a shop, with a different brand name!


--
Michael Chare

Roberts Radio Alarm - clock not setting
 

Michael Chare wrote:

Whilst I like the idea of the clock being accurate, I have never thought
that it worked very well. Some time ago whilst walking in Luxembourg I
saw a similar radio in a shop, with a different brand name!

Yes, Roberts Radios are mostly marketed as Sangean around the rest of
the world. It makes a mockery of the 'British' Roberts brand as
they're made in the Far East somewhere I believe.

--
Chris Green
·

Roberts Radio Alarm - clock not setting
 

No 60khz is longer than long wave actually.

I doubt the same receive er is used for the time as is used for the radio
am, but I guess both coils might share the same ferrite.
What wavebands does it actually cover? I had a radio medium and long which
was not good on those bands, somebody had dropped it and broken the ferrite
rod in half and the wires from one of the coils were severed. No real way to
repair it after that, sadly.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Chris Hogg" wrote in message
...
On Mon, 29 Jun 2020 11:38:05 +0100, CD wrote:

Hi
I picked up a nice Roberts radio alarm at a car boot. It has a feature
whereby it automatically sets the time on it's own via the Rugby[1] time
signal.
However, this feature isn't working & a scan through MW has little to no
reception.
I deduce from this that there's no reception of the 60kHz signal getting
through.
I'm not averse to taking it apart & having a look inside, I'm guessing
an issue with the ferrite rod aerial inside? Anything else I should be
looking for in particular?

Cheers

[1] I know it's moved from Rugby now.

Are you sure it gets its time signal from NPL Althorne? I ask because
I have a Roberts radio, much more recent than yours by the sound of
it, that gets its timing from the DAB signal. If the DAB signal is not
available, you have to set the time manually and hope it keeps
correct.

If you're certain yours gets its signal from Althorne, then try just
moving the radio to a different place in the house, as in the past
I've found the Althorne signal not easy to receive, and very dependent
on receiver location. Does your radio have a telescopic aerial? If so,
is it extended? Is 60kHz medium wave? I'm pretty rusty on that sort of
thing, but it has to be long wave or beyond, surely (the long
discontinued BBC Light Programme on Long Wave was at 1500 metres or
200kHz on the dial).

This may give you some more info https://www.npl.co.uk/msf-signal


--

Chris

Roberts Radio Alarm - clock not setting
 

It will be a very large coil, probably on a ferrite rod, from memory.

Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"CD" wrote in message ...
On 29/06/2020 12:10, Chris Hogg wrote:
Are you sure it gets its time signal from NPL Althorne? I ask because
I have a Roberts radio, much more recent than yours by the sound of
it, that gets its timing from the DAB signal. If the DAB signal is not
available, you have to set the time manually and hope it keeps
correct.

Yes, it's pre DAB. I downloaded the manual that confirms it gets the MSF
signal.

If you're certain yours gets its signal from Althorne, then try just
moving the radio to a different place in the house, as in the past

I did go from down to upstairs but will try other locations.

Does your radio have a telescopic aerial?

It's a loose wire affair, common on clock radios. It gets FM on this OK.

Is 60kHz medium wave? I'm pretty rusty on that sort of
thing.

Not sure, maybe it has another antenna for the MSF?

Roberts Radio Alarm - clock not setting
 

Brian Gaff (Sofa) wrote:
No 60khz is longer than long wave actually.

I doubt the same receive er is used for the time as is used for the radio
am, but I guess both coils might share the same ferrite.
What wavebands does it actually cover? I had a radio medium and long which
was not good on those bands, somebody had dropped it and broken the ferrite
rod in half and the wires from one of the coils were severed. No real way to
repair it after that, sadly.
Brian


It's a different ferrite.

It's also not a common ferrite for 22KHz to 60KHz.
The ferrite rods, some of them, come from Russia.

The ferrite and coil are also resonant, and a C is
added to the circuit which gives the desired resonant
frequency.

The coil of wire can be smaller, because the "clock module"
has to fit in all sorts of clock movements. Without the
ferrite, the loops of wire require many many feet of material.

In this picture, is a 60mm rod, with a 20mm wide section
of enameled fine wire. Under some black tape next to the
flat coil section, is a capacitor selected for "resonance".
The ferrite assembly in this case is tuned for 60KHz.
Other ferrites-plus-cap are tuned for 77KHz or whatever.

https://www.galsys.co.uk/modules/how...-receiver.html

Alaso shown on the page, is a "receiver" assembly, with
a glob-top chip on a module. The chip is raw silicon placed
on the module, wire bonded to pads on the module PCB,
then black plastic is poured over top. National Semi used
to make some early digital clocks this way, with glob top
chips. It's somebodies idea of a "money saver", which given
the bother this causes, likely does not save any money.

You can buy the receivers as a separate item sometimes,
and then the digital bits you design, have to pick up the
"defacto standard" output of the module and do something
with it.

Even wall clocks can use those module-solutions, for the
RF to digital part of the thing.

This module is for the German LW transmitter, at 77.4KHz.
it happens to have RS232 output (whereas other applications
may not want the RS232 level shifter to be present, and
instead, just have TTL or CMOS levels for the serial messages).

https://www.hkw-shop.de/out/media/FM...M_DCF-U_DD.pdf

You would connect a pre-tuned 77.4KHz ferrite plus capacitor, for
easy reception (compared to running out in the back garden
with a 20 pound spool of copper wire to make an "air core" antenna).

I think this may have been the site I visited years ago,
with some of the details.

http://www.creative-science.org.uk/MSF.html

And at the bottom here, is his "air core garden antenna".
90 turns of wire, on a square frame 2 foot per side or so,
so about 720 feet of wire. The wire looks fairly substantial too.
It's not 40ga magnet wire or anything. Probably an attempt at
reduced loss due to resistance.

http://www.creative-science.org.uk/MSF3.html

"Without the high permeability ferrite the air cored loop
has to be ca. 500 times the size for an equivalent ferrite rod antenna.
This one has 90 turns in total. I used the same Mosfet pre-amp with this.
It works well, about as good as the two, but not as good as the
eight ferrite rod antenna."

So he built one ferrite antenna, with eight rods of ferrite inside.

There was a guy in sci.electronics who had some sort of evil plan
to make an antenna with enough signal, it would go directly into
his DSP solution :-) I don't know if he ever succeeded or not.
People occasionally make a project out of this stuff,
even when it's been reduced to "easy module" status.

Paul

Roberts Radio Alarm - clock not setting
 

"Brian Gaff \(Sofa\)" wrote:
No 60khz is longer than long wave actually.

That's why I put 'LF' in brackets in my comment. LF is specifically
30kHz to 300kHz (with MF being 300 to 3000, HF the next decade, and so
on).

--
Chris Green
·

Roberts Radio Alarm - clock not setting
 

On 29/06/2020 12:36, CD wrote:
On 29/06/2020 12:10, Chris Hogg wrote:
Are you sure it gets its time signal from NPL Althorne? I ask because
I have a Roberts radio, much more recent than yours by the sound of
it, that gets its timing from the DAB signal. If the DAB signal is not
available, you have to set the time manually and hope it keeps
correct.

Yes, it's pre DAB. I downloaded the manual that confirms it gets the MSF
signal.

If you're certain yours gets its signal from Althorne, then try just
moving the radio to a different place in the house, as in the past

I did go from down to upstairs but will try other locations.

Does your radio have a telescopic aerial?

It's a loose wire affair, common on clock radios. It gets FM on this OK.

Is 60kHz medium wave? I'm pretty rusty on that sort of
thing.

Not sure, maybe it has another antenna for the MSF?



yes. given that the ferrite is brittle and heavy, it's probly been
dropped - the good news is that you SHOULD be able to glue any bits
together and resolder any broken wires


--
Climate is what you expect but weather is what you get.
Mark Twain

Roberts Radio Alarm - clock not setting
 

On 29/06/2020 21:48, Paul wrote:

It's a different ferrite.

Thanks for all that. I'll report back on what I find when I open it up...