They may have mechanical reels, but those reels are driven by electric stepper motors that are fully controlled by a microprocessor. The pull-handle, which used to engage gears and cams that mechanically spun the reels, now simply operates an electrical switch connected to the same circuit as the switch under the SPIN button. Many progressive machines are also reel spinners, but this post only covers games with a static (unchanging) top jackpot.

Although the variety of spinning reel machines may seem endless, they come in just four main styles. All other differences have to do with the kinds of symbols used and the amounts of the payouts.

Following are the four basic types:

Coin Multipliers
In most casinos, multipliers are very popular machines. Multipliers are single-payline games where the number of coins bet on one spin multiplies the potential payouts. When this mathematical relationship is exact, the game is called a true multiplier. Bally’s “Double Trouble” is an example of a two-coin true multiplier.

In most games, however, the top jackpot is higher than the multiple when the maximum number of coins is bet. This version is called a modified multiplier (see illustration). The purpose of a modified multiplier, of course, is to encourage the player to bet the maximum on every spin. For instance, on most three-coin multipliers, if the top jackpot pays one thousand coins for a one-coin bet, the second coin will pay two thousand coins, but the third coin may pay four thousand coins (instead of three thousand coins), or even five thousand coins or more. Hence, the conventional advice is to always bet the maximum number of coins. However, this is not necessarily good advice, as will be explained in the strategy section.

Typical modified multiplier paytable.

Multi-Line Games
As you visit different online casinos, you will notice that there are plenty of reel spinners with multiple paylines. In the industry, they are called line games because the paytable is payline-driven. While a single-payline slot machine has one horizontal line across the window, a three-payline slot has two extra horizontal lines, one above and one below the center line. The extra Kinds of Spinning Reel Machines paylines are activated by betting additional coins, giving you two additional chances of hitting a winning combination. Although you may activate one, two, or three of the paylines by inserting one, two, or three coins, to qualify for the maximum jackpot benefit, you must play all three coins.

Some machines have five paylines, with two of them crisscrossing the window diagonally, giving you a total of five winning chances (see illustration). These machines take up to five coins, one for each payline, and here again, you must play the maximum number of coins to qualify for the top jackpot. From the standpoint of return on investment, the multi-line slots are perfectly fine machines if you don’t mind the higher bankroll requirement.

REEL GOOD ADVICE
Don’t assume that all machines with the same name are identical. The IGT game called Triple Diamond comes in several versions that have one, three, five, or nine paylines. Furthermore, the one-payline version comes as a two-coin or three-coin multiplier.

Testing Your Machine

Once you have found a suitable nonprogressive machine, it is prudent to first run a simple test to judge whether it is hot or cold. Do this by playing through one roll of forty quarters ($10) allowing the winnings to collect in the tray or accumulate as credits. In a two-coin machine, this will amount to twenty spins. In a three-coin machine, you will get thirteen spins, with an odd coin left over. When the roll is finished, count the number of coins that have collected in the tray, or look at how many credits you have accumulated. If your winnings are at least 75 percent ($7.50) of what you invested, stick with the machine. If not, move to another machine and repeat the test. Of course, in a dollar machine, your investment will be four times as large, but the testing principle remains the same. In any case, if after the first six spins of the test you have won nothing, the machine is cold, and you should vacate it without carrying the test any further.

If your test winnings are at least 75 percent, but less than 90 percent, the machine is marginal and you may want to repeat the test to find out if it is in an up cycle or down cycle. Should the second test turn out better than the first, the machine is probably in an up cycle. This means the machine is getting hotter, and you should stick with it. Otherwise, abandon the machine. This test does not determine how loose or tight a machine is, but only if it is running hot or cold. Even tight machines have hot cycles.

REEL GOOD ADVICE
Keep in mind that a hot cycle has a limited life, even on a loose machine. Consequently, you should be prepared to quit a hot machine as soon as it appears to be turning cold. An important clue is that it hasn’t paid off in six consecutive spins. In fact, the most conservative players will abandon their machine after five cold spins.
This testing procedure only applies to basic flat-pay machines, and not to progressives. The strategy with progressive slots is to go for the main jackpot, with little concern for smaller wins, as explained later.