Antenna Noise Bridge Low Frequency Converter 60 kHz Receiver VLF Receiver 198 kHz Converter
50 & 70 MHz Converter Audio Oscillator MSF Clock Tunable Audio Notch Filter Programmable Chime
Antenna Tuner Speech Compressor Two Tone Oscillator Sound Meter 136 kHz Crystal Calibrator



Time wrong ? MSF Clock is Exact. Never gains or loses, SELF SETTING at switch-on, 8 digits show Date, Hours, Minutes and Seconds, 0.5" and 0.3" red LEDs, larger digit Hours and Minutes for easy "quick glance" time, 24 hour format, automatic GMT/BST and leap year - and leap seconds, expandable to Years, Months, Weekday and Milliseconds or use as a stopclock to show event time, also parallel BCD (including Weekday) output for computer or alarm and audio to record and show time on playback, precise minute and seconds pulses, uses 4000 series CMOS so no microprocessor interference, receives Carlisle (used to be from Rugby, callsign MSF - "standard frequency") 60 kHz atomic time signals accurate to 1 part in 10^13 (300µs in 100 years), built-in antenna, 1000 km range (provision for external antenna beyond), narrowband (100 Hz) superhet receiver, 50dB agc range, can drive "S" meter, 3 kHz (audio) IF, receiver board (antenna, serial data output, 10 mA supply) can be remoted (3 wires), serial data output 8 V = carrier, 2 V = break, Seconds, Minutes and BCD outputs 0 - 10 V, Weekday as Wednesday = 3 etc, connections by terminal block, polarity protected, needs 12 V at 150 mA, 5 x 8 x 15 cm, 400 g.

"complete and well documented", Radio and Electronic Constructor.
"particularly satisfied with the pcbs", BIL in Rochdale.
"neat looking", CMT in Malta.
"interference immunity higher than other makes", RAF in Sussex.
"worked first time ... superb kit", MDA in Luton.
"very good signal", RWD in Saudi Arabia.
"well made, very interesting", PC in Eire.

This fun-to-build kit used to include all parts, tinned drilled fibre-glass pcbs, pre-wound coils, case, connectors, screws etc as well as detailed assembly and operating instructions including circuit description and diagram, all decoding details and was priced at 97.90 including VAT and UK postage.
Please e-mail for the latest price reduction, details of payment and any extra parts now neeeded.

The MSF Clock was launched in the late 1970's (e.g. Short Wave Magazine Nov 1979 page 510) as the world's first commercial Radio Controlled Clock. By the early 1980's the volume of sales was enough to influence the National Physical Laboratory in finding another transmitting site to continue the time signals after the dismantling of the huge VLF antennas at Rugby.

BST to GMT Converter

BST to GMT (or any other time zone) converter circuit in Wireless World, 1981 Aug, page 56.

Analogue Display of MSF Time

Use the Seconds and Minutes outputs of the MSF Clock to drive analogue stepper clocks from the MSF Clock's internal 11 V supply as follows.
SYNCHRONOME needing 2 pulses/minute - adjust the potentiometerfor 2 pulses on the minute.
SYNCHRONOME with 3000 ohm coil needing alternate polarity 24 V each minute (just works with 11 V)
Domestic QUARTZ movement, 1.5 V battery driven, 60 ohm coil needing 1 pulse each second.

Telephone Answering

Find the date and time of every telephone call you receive. Record the 3 kHz audio output of the MSF Clock with the message, then play it back through the MSF Clock to see the Date and Time. Play back through a Tunable Audio Notch Filter set to 3 kHz to hear the message.


Find the date and time that an event occurred. Change the connection between "Data 1" on the RF board and "Data 1" on the Logic board to the diode gate consisting of the 2 diodes and 18k and 82k resistors shown for displaying Milliseconds. Use the event to connect 11V to the junction of the diode and the 82k resistor to freeze the display.