I certified (NAUI) in 1978 in Hawaii with local instructor by the name of Joe Ho while stationed there with the 25th Division. We did ALL our work in the ocean on Waikiki beach. The tanks were steel 72's with a little plastic backpack with D ring's on the straps to fasten them (no fastex buckles). You had to know how to rig the belt with a loop through the D ring so you could just pull the end and it would pop open. We used old May West vests as BC's and I still have my original mask and snorkle (can't use them, plastic and rubber is all shot). Had to take the reg out of your mouth to adjust bouyancy.
Our open water checkout dive in Haunauma Bay on Oahu included a 30' free ascent with an instructor with our reg in hand. Then swim back down and watch everyone else do it. Longest 30' of my life but a great thrill when it was done.
We too learned to breath off a tank valve (strain the water out with your teeth, Joe said) and with a regulator with no diaphram in place (toggle the valve with your finger).
Dive plan was the same as the others mentioned, set your watch when you went in the water so you know how long you were down. One of my buddies had a depth gauge and we ran off the navy tables. Did reef exits in the surf and always cut my knees on the coral, then had to douse them with peroxide so I didn't get coral poisoning. Usually made two dives in the morning and then drank beer all afternoon.
Newest technology then was an aluminum backpack with hook shaped, padded aluminum straps over your shoulders and a web waist belt. Seems to me we used to call this a Hawaiian Pack or some such thing. I remember the first time I saw a fellow with an Octo, couldn't figure what it was for as we always shared a regulator when in need. In training we once kept 10 people passing around the same regulator for 10 minutes, just for practice. That same fellow had a US Divers rig, with a HARD wing. Plastic covers with a soft bladder inside on either side of his tank. Just the latest thing from Jac Cousteau!
I LIKE the new gear that we use now. I think octos and such are a good idea and I carry a pony bottle when I dive wrecks and deep. I LOVE the drysuit technology and wouldn't be able to dive here in Michigan without it. A dryhood, and drygloves make great sense when the water is 36 degrees at depth. Backplates and wings work so well, that I wouldn't consider going back to the old jacket style rig. Dive computers are some of my favorite things as well. The new technology is really nice and makes for easy diving in all conditions.
