There's no mention of unscheduled outages on the NPL website here, nor a July shutdown.Switch-offs are only for short periods during scheduled outages, so perhaps your clock is suspect. I find that putting my instruments by a window can help them to find the signal.

A few days ago I noticed that my home made frequency standard (with built in clock) was not receiving MSF.

I checked the NPL website, there was no mention of an MSF outage. I guess the guys at the transmitter site were having a bad day!

JimB

My home is a poor radio location in a valley, and because most of the local power supply is delivered to houses on poles, not buried, it's electrically noisy here. Power cables and telephone wires transfer radio interference throughout the village.

I own a Very Low Frequency receiver, and can measure MSF (60kHz Cumbria, England) and DCF77 (77kHz Frankfurt, Germany) relative to what else is going on in the band. MSF is weak here, barely strong enough to work a clock, and local interference is often strong enough to drown it. This is listening on a deaf indoor ferrite rod antenna borrowed from an MSF clock.

A DCF77 clock might work here, the signal is several times stronger than MSF, perhaps because valley is more open to the east.

The very simple receivers and antennas used in ordinary radio clocks being weedy and vulnerable to interference probably explains why they work intermittently. On a good day, the signal from Cumbria is strong when the clock tries to synchronise, and the band quiet. Success! On a bad day, propagation is poor and the band full of noise, natural or man-made. Perhaps the chap next door is playing with his VFD powered 5kW lathe…

Dave

I built an MSF receiver and had a hell of job setting it up until I switched the computer monitor off that was nearby, this was years ago when monitors were CRT based. It was emitting a strong signal close to 60khz and swamping the MSF.

Mike

Edited By Mike Poole on 20/07/2023 11:21:57