RL and RLC (+ others) circuits

I'm doing an electrical apprenticeship and we are working on RL and RLC (+ others) circuits which involve a lot of different formulas that need to be memorized and I was looking for a calculator that would store these formulas for me. I was also wondering what the point is with the USB cable?
The calculator I have now is a TI-68 I love it but it does not have the memory I require.
could someone tell me if this is the right calculator before i go out and spend over $150 on this unit, + would are the limitations on this thing, will it store words along with the formulas for example could I put into memory: series=2*pi*F*L

Thanks for any info

I don't actually have a 68, so I'm not going to say that it's a bad choice for your needs, but I will say that the 83 and 84 series seems like a good choice, as they are programmable (the reasoning for this section of the DevHardware forums, of course), you can include words, although not for variables, and you can store equations like the ones you said you need memorized (which I would recommend you actually do).

The 83 + (One of the two graphing calculators I own) is about $100, has significantly less memory than the 84, and goes slower, but still has the speed and space for your needs and then some if you program it right, along with an almost identical programming language, just without some commands and the such, along with it being one of if not the most popular graphing calculator on the market. I would recommend buying this own if your 68 doesn't fulfill your needs, but for about $20-$30 more, you could get the 84 + SE, which has (I think) 9 times more memory space, and goes 2.5 times faster.

Make sure that you really need a different calculator before you buy one. And if you get a 83 or 84, send me a private message with all the equations you need, and I'll send you a program you can enter directly into the calculator, with everything you need.

Thanks for the offer. I ended up getting the TI-84 (silver edition) and seem to be doing ok with it. I am able to program it and use most of the functions, can't seem to delete any programs I make??? and I am currentlly trying to find out how to do number convertions (hex-to-dec, bin-to-hex). any insight to these problems by all means, help.

To delete anything, press [2nd],[+](Mem),[ENTER](1. All), and you'll be able to archive, unarchive, or delete anything. For the 83 and 84, you have to have a program in the RAM to use, but the RAM is small, so if you have too many programs, you have to put them into the archive, which means you still have them, but you no longer can use them. Applications, AppVars (Application Variables), and some programs don't have to be unarchived to be used (These may not be the only ones, but I don't have my calculator on me at the moment so I'm going by memory). Any-who, on the 83 and 84, you can only use base 10 numbers, but you can make a program to convert one to another. I made a base 10 to binary converter way back when I was in Intro to Java, and we had to know binary, base 10, and hex, but I got rid of it a long time ago. If you want, I can make one for you with binary to and from base 10, and base 10 to and from hexadecimal. Doesn't seem like it'd be too much of a hassle, but I will tell you something. Because in base 10, you only use number characters (i.e. no letters), when I do make a hexadecimal converter (assuming you want me to for you), it will have to output the number as a string, because otherwise, it may think of it as a bunch of numbers being multiplied together (3A78B0, would be interpreted as 3*A*78*B*0). The binary converter can be a normal number (variable), but the calculator will still view it as a number (10 will interpreted as ten, not two).

Again, just tell me if you want me to make it for you. I don't mind. I will have some free time later today and Sunday. It shouldn't take very long at all to make.