Old Tech

The other day, while searching for something completely different in the darker recesses of our house I came across this piece of old tech, and got totally side tracked. For those with GPS watches and mapping apps to help guide your way up a mountain, across the Clyde or even to the local chippy, this trip down memory lane will hopefully be of interest.   

Known affectionately as “the brick” for obvious reasons, this for the uninitiated was one of the first mass produced hand held GPS receivers which, as we all know, revolutionised how we navigate, search and locate offshore wrecks. Before GPS and high definition echo sounding equipment, finding and locating wrecks any further offshore than 1-2 miles in a small boat was a bit pot luck. We had to rely on transits or bearings lifted from hydrographic charts, and then trawl about with a grapnel on the end of a rope in a bid to hook some metal. If you could afford it, a paper trace echo sounder was most useful as the revolving red diode sounders were not worth the bother.

Ian Crawford and I purchased the GPS unit in 1990.  At the time it was a pound short of a grand, a lot of money back then but the salesman at Boat Electronics in Troon seemed happy enough. We soon got our head round the inch thick instruction manual and started searching for new and perhaps un-dived wrecks in the Clyde and off the West Coast. 

Without doubt it opened up many new sites and wrecks to us, which we were able to dive and write about in our books. The ability to provide GPS positions certainly gave us the edge and was most useful for our readers, as long as you had your own GPS! One downside to the unit was its ability to chew through 6 AA batteries in under an hour, and this was resolved by another visit to Boat Electronics and the purchase of a 12v adapter.

Today we use a MFD unit or multi function touch screen device that is packed full with software and gizmo’s for position fixing, CHIRP sonar, side and downscan sonar, radar, controlling aerial drones, monitoring your engines and fuel consumption, music etc etc. Below is a typical example of what information a unit in the price range £1-1.5k can provide you with on one screen, which are now user defined into 2, 3 or 4 windows per screen. I would caution you to do your research before buying, some are better than others and the sales literature always looks better than practice, definition is always reduced as you go deeper and most of these cheaper units are pretty poor below 55-60m.

Hindsight is a great thing, and while this unit still functions perfectly a quick look on Ebay confirms its probably worth about £20. The advances in marine electronics in the last 20-30 years have been astounding, new technologies and computer chips bring improvements in speed of operation, size, quality of image. The functions available continually change so its maybe worthwhile if you update your kit every 4-5 years, to avoid being left with a battery munching £20 brick!