First off, yes the instructions are in the EZNEC manual (page 60). I eventually found them by searching the manual. And a further yes, they are a bit less than intuitive.
With you licensed copy of NEC 5.0 X.13 downloaded, and EZNEC installed on your system:
- Unpack the NEC 5.0 X.13 folder, putting a copy of the whole folder in the \EZNEC 7.0\Docs\ folder EZNEC previously created.
- Start EZNEC, selecting Options>Calculating Engines>NEC 5
- When prompted navigate to the .exe in the NEC 5.0 X.13 folder and select the non-32bit .exe (unless you know you need the 32 bit one for your system, then us that one) (The manual file names are for an older X.11 version of NEC 5.0)
- The system should ask you to associate model file names with the engine, to which you say yes.
- Save the new configuration as Options>Default
- You can later confirm through EZNEC Utilities Menu that all is good.
If you are running the free trial version AutoEZ and have downloaded the NEC 5.0 X.13 test models AutoEZ provides, you will find they won’t run as they have too many elements for the trial version. The NEC 5.0 X.13 Antenna Model test files work under the licensed version of AutoEZ though.
Note that NEC 5.0 updated how Objects are Placed (read page 97) and there are some tradeoffs (see table on page 180). The appears to mean that if you want to run your models both with the built-in EZNEC NEC-2 (called EZCalcD) and the External NEC 5.0 engines, you likely will need to make two models to properly place the objects that make up your antenna model.
- EZNEC can be found at https://eznec.com/
- Link to the EZNEC 7.0 Manual – https://eznec.com/ez70manual.html
- Link to the NEC 5.0 LLNL Page – https://ipo.llnl.gov/technologies/it-and-communications/nec-v50-numerical-electromagnetic-code
- Link to AutoEZ – https://eznec.com/AutoEZ.htm