Can anyone identify this ?

[G1MQQ]

Hi and greetings

I have been given the instrument shown below. It was the property of a deceased watchmaker who like myself was also a radio ham.

The donor believed it might be an item of radio equipment.

The instrument says VEGAL made in England. No other marks or serial numbers. When plugged in the unit hums, I don't think it's mains hum as the frequency sounds too high, the loudness being controlled by the volume knowb.

The switch is marked WATCHES, CLOCKS CLOCKS +  10 and T. FORK plus various numbers.

The display ("Nixie tubes" ) displays numbers, could be frequency, time etc.

The jack socket is simply marked INPUT

I recall back in the 60's (yes I'm that old) an acquaintance had a Bulova accutron watch who's mechanism was controlled by a vibrating tuning fork, which could be heard humming if held near the ear.

SO!! flash of inspiration.

1) The insrument was owned by  a watchmaker and the switch positions obviously relate to timepieces

2) It has a setting marked T Fork

3) It hums

Is it some sort of frequenct standard/calibration device/diagnostic aid for tuning fork watches ?

Can anyone help

Many thanks in advance

Geoff

[spectre6000]

You said it has nixies (super cool!)? What's the dial show? Anything on the back/sides/bottom? Data plates, markings of any sort, etc.?

[G1MQQ]

 

17 minutes ago, spectre6000 said:

You said it has nixies (super cool!)? What's the dial show? Anything on the back/sides/bottom? Data plates, markings of any sort, etc.?

Absoultely nothing. Not even a serial number. Numerous web searches turn up nothing either. I've evn tried reverse image searches.

Close up od dial in pic below but just numbers, no units

[spectre6000]

What are the numbers on the rotating dial? Neither image is clear enough to make out what's going on there. The scale/range might be a clue.

Take whatever cover(s) off, and let's see the guts. More clues there lie. There are enough EE types on here to possibly be able to figure out what's going on by the circuitry/layout.

[G1MQQ]

It's not immediately obvious how to ge the covers off. There are no obvious case screws. Only screws are holding the feet on. Maybe removing these and the chassis will slide out. I'l  give it a go. meanwhile here are the numbers.

 

[G1MQQ]

17 hours ago, spectre6000 said:

What are the numbers on the rotating dial? Neither image is clear enough to make out what's going on there. The scale/range might be a clue.

Take whatever cover(s) off, and let's see the guts. More clues there lie. There are enough EE types on here to possibly be able to figure out what's going on by the circuitry/layout.

Covers off.

No new info or markings except for component values as you would expect.

The device is obviously custom made. It's built on "Veroboard" and the Chassis is perspex with panels glued together.  Some components (large PSU capacitors) appear glued down.  The ic's as far as my researches show are part of the Nixi tube driver curcuitry Fairchild 9390/7490 so no help there!

 

[spectre6000]

My money is on a timing machine. I'd love to get my hands on something like that to just dissect the circuit. Looks a super clean and professional homebrew job, but homebrew all the same. The photos aren't high enough resolution or thorough enough to really tear it apart, but I imagine you've got your power supply section in the back (photo) left corner, and possibly continuing on the rear of the nixie driver board. I imagine that's an amplifier on the right side of the bottom of the case for the input, and then the board on the side of the case, front-right is where the money is made. Some sort of counter circuit.

I imagine the way it works, is the "T. Fork" setting is for calibration to a known, high accuracy/frequency reference, and the other settings are in hertz or aliased for common regulation frequencies. I'm guessing 1hz for big clocks ("Clocks"), maybe the other is for half second beat rate clocks ("Clocks +10")... one of the clock guys would have to weigh in. I imagine "Watches" is 4hz, and the rest are directly stated. The dial is probably registering #beats in some fixed time period. This is just an educated guess. It could be more confidently nailed down with an in person inspection, many more and more detailed photos, etc., but for what's available, that's the best I've got.