Rewbichron MSF receiver module from Ambit

[DrStrangelove]

Does anyone remember this thing?

I bought one many years ago from Ambit & it never worked.

Another example I found in work that didn't work either.

Then again the 1976 receiver from Wireless World needed a lot of tinkering to make it function reliably especially in a steel frame building.

[PerdioPal]

I don't remember the Ambit one but I have made a few MSF receivers in the past, some even worked! The best ones today are the really cheap single chip jobs.
I have always fancied making a pendulum clock with passive MSF sync. i.e. a tuned circuit (probably with a large ferrite antenna) with detector and a solenoid to "kick" said pendulum. I did a few sums and there isn't enough energy to run the pendulum and associated clockwork, but maybe enough to sync one.

Picture of the Ambit may help.

[DrStrangelove]

I've always wondered if the Rewbichron receiver was designed by someone who lived a good deal closer to Rugby than I did.

[Mike Watterson]

I've an old VFD alarm clock radio with MSF receiver. It didn't work at all so I fitted a much larger ferrite rod. It can still take over a week before the time sets. Stupidly, like some DAB-FM clock radios, there is no manual setting.
I have a DAB-FM clock radio sold in a local shop and it can't use FM-RDS or manual time setting, only DAB. DAB was turned off ages ago and only had 43% coverage.

A cheap Lidl clock / thermometer works OK off the UK MSF, though outdoor temperature sender failed.

What will happen with 'dumb' MSF set clocks in Ireland if we abandon the twice yearly time hop foisted since about 1917 and UK does not? It won't happen while N.I. is in UK, but that has only been since 1922 and won't last forever. Demographics more than politics.

Try an outdoor 6″ rod aerial on the Rewbichron with either transformers for coax or just random ribbon using plastic spacers.

[Mike Watterson]

I've always wondered if the Rewbichron receiver was designed by someone who lived a good deal closer to Rugby than I did.

Possibly, though MSF has moved north? Not Rugby now.

[DrStrangelove]

It didn't work 35 years ago when the transmitter was in Rugby, so it's got very little chance of working now it's in Anthorn.

Some of my cobbled together MSF receivers work rather better than that thing did.

I must dig it out sometime & have another attempt to make it function.

Here's the article on page 76 of the April 82 Radio & Electronics World.

https://www.worldradiohistory.com/UK/Rad...-04%20.pdf

[Mike Watterson]

I see it's got no RF amp, just a FET buffer, and simply select on test for the ferrite rod tuning cap. A LW radio aerial coil on 4″ or longer rod and about 7x the normal fully closed tuning cap to approximately tune. Fine adjustment can be with a polycon tuning cap and/or moving coil to end of rod.

So fit a coax socket at C3 100nF and feed 100 Ohms from R1 to that point for supply (optionally via a 10mH to 100mH choke instead of 100 Ohms).

Put a coil & cap (tuned to 60 kHz) and FET source with fixed 2K2 decoupled with 100nF. Then drain to coax. The box can go on a windowsill top of cabinet or outdoors.

At 60KHz the FET has adequate input impedance as an amp rather than a buffer.

[DrStrangelove]

Found the afore mentioned Rewbichron receivers: one sans ferrite rod assembly, the other sans chip.

If I find a round tuit something may transpire but I'm not holding my breath.

My homegrown receivers seem more effective.

[Mike Watterson]

Certainly effort was put into the digital part and the RF part is clueless.

[DrStrangelove]

Certainly effort was put into the digital part and the RF part is clueless.

Yes it seems less than inspiring.