So.. you found your HP 41 the other day and want to relive some of the glory days.

Wouldn't you agree? The HP 41 Series is one of the most powerful mini-computers ever made. If you attended university in the 1980's, this was the device to have if you wanted to survive technical classes!

Back to the Basics

If you have lost - or have not read the manuals in a while you can find them for sale on ebay. This is a great start. If the regular and advanced users manuals were light reading for you, look for some of the following books:

• 41cx manuals (vol 1 and 2)
  
• PPC Rom Manual- book bound- Very comprehensive
  
• Synthetic Programming made Easy
  
• An Easy Course in Programming/Using the HP41
• Inside the HP-41 by Jean-Danield Dodin
  
• HP-41 extended functions made easy - Keith Jarett
  
• HP-IL system dictionary
• HP-41 M Code for Beginners by Ken Emery
• Synthetic Programming on the HP 41C by W.C. Wickes
  
• HP book, "HP 41/48 Transitions" by William Wickes
  
• Calculator Tips and Routines- Dearing
• PPC News letters
  
• CHHU News letters
  
• CONTROL THE WORLD WITH HP-IL Book By GARY FRIEDMAN
  
• Extend Your HP-41 by Jedrzejowicz
• HP 41 Advance Programming tips by Alan McMornack& Keith Jarett
• Programming the HP 41 C/CV/CX by Thomas Adams

Hardware -Upgrade your 41C/ 41CV

The 41c was the most basic Calculator in the series. Look for modules to expand the memory first and then the functionality:

• 4 Memory Modules or 1 QUAD memory module (these are unnecessary if you have the 41CV)
  
• Extended Functions Module- adds some critical functions, and a little Extended Memory
  
• Time Module- optional but nice to have if you want to use the timer.
  

If you have all three you are on par with the HP 41cx.

Hardware - Upgrade your 41cx

• Look for two single Extended Memories, a Dual X-MEM, or even a Rare TRIPLE module with X-Functions+2XMEM (41C/CV only)
  
• PPC ROM This is the most comprehensive and extensive programming tool available
  
• HP-IL module- This will allow you to start talking to other machines, drives, and printers
• Extended I/O Rom- This is hard to find, but nice complement to the HP-IL module.
• Optical Wand- This is the easiest way to get programs into the 41.
  
• Magnetic Card Reader- The second easiest way to load programs. They are prone to GUMMY wheel- watch out!
  
• Thermal Printer- Excellent optical output device. Uses no ink.
  
• Tape Drive- Good for backing up ROM images or other media
• Zenrom, CCD, or HEPAX- These advanced Programming ROMs are excellent for power users
• You can also expand your module collection. Check out the complete list of modules in the hp-collection
  

Custom Add-ons for the 21st Century

There are still some really cool add-ons for the HP-41 family. I recommend :

• Clonix,
  
• NOV-32
• NOV64
• MLDL-2000.

The HP41 in 21st Century

After you've mastered the hand-held tools, you may want to plug in your programs to the computer!!
I Recommend:

• EMU41- a PC emulator for the HP 41 family (also sister to the EMU71)
• Download One of several iphone apps that simulate or emulate the HP 41cx
  
• Get the full manuals on DVD from the Museum of HP and from HP41.org
• Get a ISA-PC card so you can connect to an older PC for program download
  
• Look for the PIL-BOX USB adapter from JFG- allows HP 41 to be connected VIA USB to a modern PC (release 2009)