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Discussion in 'Antennas, Feedlines, Towers & Rotors' started by KD7MW, May 2, 2021.

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  1. KD7MW

    KD7MW XML Subscriber QRZ Page

    How do these two programs stack up against each other in terms of ease of use and getting things done with minimum fuss? Particularly for someone who would not use them every day and probably won’t attain guru-level proficiency?

    I’ve fooled with both EZNEC trial version and 4NEC2 over the years without really getting to know either well. Mostly for simple things involving dipoles, inverted vees and verticals on a suburban lot. I do have the impression that 4NEC2 has some very nice graphical features, but has both a steep learning curve and mediocre documentation. EZNEC’s entry seems more primitive, but the program seems more widely used and better documented.

    Today I was checking how far away the end of my 80m inv. vee would have to be from my neighbor to be in compliance with MPE standards. 4NEC2 did the job after a couple of hours of me head-scratching. It reminded me that I really ought to decide on one or the other program. Any thoughts on their comparative strengths and weaknesses?
  2. G0VKT

    G0VKT Ham Member QRZ Page

    I will follow this as I also need to work out my compliance but have never used any modelling software.

    Paul G0VKT
  3. WA7ARK

    WA7ARK Ham Member QRZ Page

    Both have a huge learning curve. Both ultimately use the same underlying NEC2 Method-of-Moments algorithms and computation engine.

    A lot of learning has to do with how antennas work independently of modeling. You need have an expectation for what an antenna is going to do before you model it. You need to have some basic electronics understanding, including voltage, current, complex RF impedance, power, efficiency, losses, transmission lines, SWR, transformers, impedance matching, resonance, LC circuits (traps), etc.

    A lot of the learning is the art of constructing a model which follows rules imposed by the NEC algorithm, such as how to model:
    3 dimensions and the cartesian coordinate system
    wire segmentation
    wire junctions
    sources and their placement
    earth connections,
    ground absorbtion
    feedlines and their radiation
    matching networks
    traps and other loads.
    testing the model for accuracy.

    For a casual "what if" interest in antennas, most folks do not have the motivation to get up the learning curve... It is easier to ask someone to "model it".
    KX4OM, WB5YUZ, K2XT and 1 other person like this.
  4. KX4O

    KX4O Ham Member QRZ Page

    I have the paid version of EZNEC Pro (Pro/4 at work) and 4nec2. Because EZNEC was my first foray into the NEC simulation approach I used it for years. Then I wanted to do some automated optimization. 4nec2 has such tools built in. Then I wanted to increase the speed of the NEC engine. NEC-MP was a drop in replacement for the underlying NEC engine 4nec2 happily uses. I'm still very happy to have both programs available for my use, but the nod goes to 4nec2 for my needs both amateur and professional.
  5. K6CLS

    K6CLS Ham Member QRZ Page

    4nec2 is free, the right price! Unlike eznec it has no silly limits on number of segments, memory, etc.
    EA1DDO likes this.
  6. WA7ARK

    WA7ARK Ham Member QRZ Page

    Since I have learned to write proper models, I have never run up against the 2000 segment limit imposed by EzNec+.

    The 20 segment limit in the free, demo version of EzNec is very limiting. It is just enough to properly model a dipole.
  7. K6CLS

    K6CLS Ham Member QRZ Page

    EZNEC+ is $150.

    it ran out of segments trying to simulate KF2YN Boxkite.

    Funny, the design was in an ARRL book, I would imagine they would have tried the design files on the included CD. In dact, the CD was missing about half of the designs in the book!! It is too much to ask for any editing and quality control from that book-of-the-month club.
  8. UA3TW

    UA3TW Ham Member QRZ Page

    4nec2 interface is difficult for me and it does not have transformer function. That is why i use EZNEC-6 and AutoEZ for optimization. They are dear and i would be hardly able to buy them but got them as a gift or rather a fee.
    But i need them only if phased arrays are calculated and transmission lines or hybrid couplers are included.
    Othervise i use MMANA for all antennas with parasitic elements as multiband yagis and the like. IMO MMANA reflects reality the best way if antenna is high enough, halfwave up at least, that i always have.
  9. K1LH

    K1LH XML Subscriber QRZ Page

    I'd have to agree with Nick :) I struggled with 4NEC2. Started with MMANA, moved to EZNEC to gain the ability to model complete systems including transmission lines, L-networks, wire insulation etc, and the high accuracy ground model for low HF antennas. The user guide included with EZNEC walks you through the features using practical examples. The cost is well worth it for the good manual and complete range of features, probably the best money I have spent on the hobby next to a good antenna analyzer and some good books in regard to how much it has helped improved my knowledge.
  10. EA1DDO

    EA1DDO Ham Member QRZ Page

    I´ve used, and I use, all of them.
    I would say;

    MMANA is the easiest one. I think is best option for entry level. That does not mean results are not good, in fact are as good as the rest of the options. Even, it is better for loop antennas because the use of Mininec engine.

    4NEC2 is my everyday option. Plots are best.

    Eznec has some very specific features but output plots are at lower level than 4NEC2.

    If you pay attention, Eznec is made by W7EL, for that reason it seems US hams are happier to use it. 4NEC2 has been made in Europe, hence is more used here. Mmana has been made in Japan, then improved by russian guys living in Germany, hence it has more users in Europe too.

    73, Maximo
    KX4O likes this.

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