How do I use the %CHG function on my 30S?


For example Percent Change from 4 TO 5 is 25:

Keystrokes are [2nd][%CHG]4[2nd][,]5[ENTER]
You will see 25.

The calculator will supply the enclosing parenthesis around 4 and 5 automatically. The [%CHG] is the 2nd function above the multiplication [x] key and the comma [,] is the 2nd function above the division key.


Thank you rsenzer. That must have been the only bloody combination I didn't try.


Not trying to "teach my grandmother to suck eggs", but you can download the little user's guide from HP:



The HP website also has manuals for the 20S and 32SII to download, but only in Spanish and Portuguese.





you touched one interesting point: why Spanish and Portuguese?

I have my own guesses, and they are related to parallel-marketing sales, but I do not understand that. I tried to download the English version of the 17BII's manual and I got only the Portuguese and Spanish options, too. I thought it was so because I was downloading from Brazil, but now you called my attention. It seems that only the HP12C (Solutions Handbook, not Owner's ManuL), HP10B and HP10BII offer the Portuguese, English and Spanish options. And the manuals I downloaded (HP17BII Portuguese and HP10BII English and Portuguese) are *.PDF files built with scanned, bitmapped images, not ASCII encoded text. Too big and no search options (HP19BII Spanish Manual is more than 23MBytes big).

BTW, I was looking at the HP10BII design and I felt something strange. I got to check for my fear feelings and I could see that it resembles the Xpander... It has the same top and bottom plastic "slice" (forgive-me I did not find the correct term for it) present in the Xpander. I also checked the HP30S, and its keyboard, with rounded-corner keys, tries to imitate the Xpander keyboard. Are these signs related to what is about to come from HP? Please, correct me if I missed something....



I think those manuals are pre-internet and probably were not saved in electronic format. The 12C applications manual is also scanned. As for why just Spanish and Portuguese, I'm curious too! I wasn't able to download them but I think my computer is very low on disk space, it has been doing some other funny things. I want to download them in the hope that I might learn a little of the languages (I'm supposed to know some Spanish already).

BTW, Luiz, are you familiar with the TI business models? I have a Business Analyst (the original one, from the family of the TI57 and TI30) and recently tried to figure out how to use it. The statistics functions I figured out because I have the booklet for the SR-51, which seems to be their source. Also the cost-price functions I figured out from the HP14B manual. When I tried to figure out the TVM program by comparison to HP manuals, some things worked but some didn't. I looked on datamath.org and rskey.org but they don't have any manuals but rskey.org did have advice on finding manuals and pointed out that TI has them for current models online. I looked there and found the BA Solar which works very similarly but with more functions, but still many things I tried on my machine gave "ERROR" or just calculated 0 instead of the correct value. Then I found a page of information for users of the Business Analyst II. It said that on that machine, the TVM program only lets you control four of the five values (N, %I, PV, PMT and FV) and the fifth has to be 0. I had been entering 0 for some simple examples, but just entering a number is unacceptable to the original Business Analyst, after pressing "clear" you must not store anything in one of the registers. For the annuities calculation either PV or FV has to be left cleared, and in the compound interest calculation (a separate mode on the Business Analyst) PMT must be left cleared, entering anything into PMT gives an error right away. Actually, I found that on the annuities I could enter 0 into either PV or FV as long as it is before I enter a value into the other. The note in the BA Solar manual explained how this limitation reduced the types of calculations that can be done.


Hi, Ellis;

which one is yours? I have an old, old BA55 and Joerg Woerner helped me sending some scanned pages - English - of the BA54. I also have the QRG, and it is in Portuguese. I told Joerg I would be working on an English version of a Brief Guide I'm about to finish.

There is one thing I did not figure out about TI's PAYMENT input. It seems to me if the PAYMENT is money paid it's positive, and if the PAYMENT is money received, it's negative. In all HP calculators, PAYMENT paid is negative, and PAYMENT received is positive. A matter of interpretation, I think.

I'm finding the scanned pages (it is in one of my 4 computers, and they are connected with each other, and I thought the pages were in this one, and they're not) and I'll send them to you. Also, the brief reference guide, even if written in Portuguese, will help clearing stuffs up.

Does it help? Is it your TI a BA54 or BA55? The most amazing thing about the BA55 is the fact that it has printing commands and it accepts a two-wire standard TI printer (from that time). We must accept that TI calculators were also innovative, and their prices (against their quality) were affordable. I had one TI57 that worked for a long time. Amazing little fellow! Easy to use and program. I used to dream of the TI58C/59 because of their programming memory (499 steps, if I am not wrong). After the release of the HP41, I simply lost their footsteps. But I still have TI calculators in great consideration.

Let me know which TI business calculator is yours.

Best regards


Yes,I think those will help because the BA55 and 54 should be closer to my model than the BA Solar. Mine is just called TI Business Analyst, it is the same family as the TI57. Here is the datamath.org page:


On this page at TI, you can download a QRG for a BA-35 Solar and a complete manual for a BA Solar, which I think TI must have supplied with the BA-35 Solar. This page is for the English version and the only other choice is French. The BA Solar manual has the notes on page viii "Special Note to BA-II Owners" which helped me understand my machine better, especially the section called "Enhancements" at the bottom of the page:


The TI website also has manuals for the BAII Plus and the BA Real Estate. I downloaded the BAII Plus manual and it appears to be much more advanced than my calculator. Here is the TI page where you can choose a manual to download:


You could be right about the "polarity" of money - here are some notes I made from the BA Solar manual (I don't think they apply completely to my BA because for annuities, it requires one of PV or FV to be 0):

PMT=0 : Compound Interest

PMT<>0 : Annuity

PMT + (discounted backward) : mortgages, loans, leases, bonds - have PV, FV may be 0 - PV, PMT flow opposite directions

PMT - (compounded forward) : savings - have FV, PV may be 0 - FV, PMT flow opposite directions

I wonder if the two wire TI printer you mentioned is the PC200? I have one that I got in a package with the TI66 from a closeout catalog. (Datamath.org indicates the PC200 was only used with the BA55 and the TI66.) The TI66 is the LCD version of the 58/59: it has a little more memory than the 58, 512 steps (the 58 had 480 and the 59 had 960) but like the 58, the 66 has no card reader. BTW, there is the 58 and the 58C, both have 480 steps but the C has constant memory. I wonder what kind of courage it takes to type in a 480 line program knowing your batteries could go out at any time? These calculators allow you to partition memory between program and registers (8 steps per register), and as has been pointed out here, some small programs need a lot of storage space.


Hello, Ellis;

I did not find the scanned pages (yet), but I had a look at the TI Business Analyst. It does not have some of the features available at the BA55, but I think common features will work the same.

I'm gonna send you further e-mails about this subject before being cut-off by censors... We are out-of-business talking about TI in a HP-exclusive forum. (I know, I'm kidding; people in here would not blame us for that... would they?)

Thank you, guys.

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