1. You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
    Dismiss Notice
Dismiss Notice
This forum does not allow a single user to have more than one username. If anyone wants to change their username contact an admin and it will be done. Multiple accounts belonging to the same member will be deleted without warning.

FT-991 MARS mod?

Discussion in 'Yaesu' started by Singularity35, Oct 5, 2017.

  1. Singularity35

    Singularity35 DU7DVE

    Joined:
    Jan 16, 2014
    Messages:
    425
    Likes Received:
    89
    I need help again masters, is there an MARS mod for the FT-991? Thanks in advance.


     

  2. sp5it

    sp5it Master of puppets

    Joined:
    Jul 9, 2009
    Messages:
    1,616
    Likes Received:
    1,536
    Google claims there is.
    Mike
     
  3. ButtFuzz

    ButtFuzz Anti-BS Advocate ● WO0WOO ● Reverend Doctor

    Joined:
    Aug 11, 2005
    Messages:
    573
    Likes Received:
    294
    Yes.
    http://radioaficion.com/cms/ft-991-mars-mod/
    This opens TX from just above the AM broadcast band to~30 MHz.
    Disclaimer: You break it, you broke it.
    Now for the next question: What about opening up UHF/VHF?
    NOPE.
    (only known way to transmit out-of band VHF-UHF is convoluted, and involves going into the service menu each time you want to have a "tx session".)
    Use the concept show here to pretty much TX anywhere:

    DON'T BOOGER IT UP!
     
  4. Singularity35

    Singularity35 DU7DVE

    Joined:
    Jan 16, 2014
    Messages:
    425
    Likes Received:
    89
    Thanks. Much appreciated. Not mine though. Friend new to HF.
     
  5. jesse everett

    jesse everett Member

    Joined:
    Mar 1, 2019
    Messages:
    30
    Likes Received:
    14
    i have done a lot of searching on this mod,i have seen the mars mod done by jumping #3 or#5.the board shown may be a japan or eu. version,it shows jumper #1 and #2 bridged. i have seen this as a way to open up uhf and vhf.do your own research on utube or or internet before trying this .as buttfuzz says "don't boger it up.".tons of info out there..also the pic. shown is backwards from what you will see from the front of the radio with the front cover removed .so #1 is on the left seen from the front. also the 991 and 991a may not be the same mod. update my 991a is one month old i did the jumer deal on jp #3 IT DID NOT WORK,i reversed it and all is good now.
     
    #5 jesse everett, Sep 8, 2020
    Last edited: Sep 9, 2020
  6. Justme

    Justme Well-Known Member

    Joined:
    Jan 28, 2008
    Messages:
    471
    Likes Received:
    430
    I did mine Mars mod, just closing the 3rd set of solder islands, 1 and 2 were factory done in my EU radio from March production run this year.
    that mod only opens up H.F., 2 meter and 70 cm are software limited in bandwidth, and several versions of the radio for different markets have it open or limited to the bandwidth used locally.
    There is no reversable way to open up 2/70 till today except softwware solutions we don't have.

    THe Mars mod needs the front taken off, removing the metal plate behind it and there is the board where the solder pads are on, be carefull what you do, i found it easy but then i have experience and good tools to do the job and take care of static.
     
  7. w9cll

    w9cll W9WDX Amateur Radio Club Member

    Joined:
    Jan 19, 2013
    Messages:
    4,094
    Likes Received:
    3,310
    Assuming they want 11 meter access?
     
  8. Justme

    Justme Well-Known Member

    Joined:
    Jan 28, 2008
    Messages:
    471
    Likes Received:
    430
    Or open up 60 meters....;)
     
    AudioShockwav likes this.
  9. ButtFuzz

    ButtFuzz Anti-BS Advocate ● WO0WOO ● Reverend Doctor

    Joined:
    Aug 11, 2005
    Messages:
    573
    Likes Received:
    294
    If all you are seeking is 11m access, just leave the radio alone. Buy a vintage 148 or something similar.

    11m performance (a misnomer) on this radio AM mode is abysmal.
     
  10. jesse everett

    jesse everett Member

    Joined:
    Mar 1, 2019
    Messages:
    30
    Likes Received:
    14
    i redid the jumper on jp3 and it is working fine.
     
  11. Justme

    Justme Well-Known Member

    Joined:
    Jan 28, 2008
    Messages:
    471
    Likes Received:
    430
    am can be improved considerably as i described in an earlier post, just a setting wrong in the engineers menu.
     
  12. ButtFuzz

    ButtFuzz Anti-BS Advocate ● WO0WOO ● Reverend Doctor

    Joined:
    Aug 11, 2005
    Messages:
    573
    Likes Received:
    294
    AM can, indeed, be improved considerably. But nowhere near the quality of a high-level AM modulated radio such as a Cobra 29 or Cobra 148. If you want to talk on a CB, buy a CB.
     
    AudioShockwav likes this.
  13. Justme

    Justme Well-Known Member

    Joined:
    Jan 28, 2008
    Messages:
    471
    Likes Received:
    430
    If you mean overdriven AM and unlimmited AM yees i bet the CB radio's have it on the FT991a.
    After you corrected the fault the am is actually quite good on the FT991A, as my counterpart QSO'ers told me even in the AM nets.
    No wideband modification known as by now so AM is limited to3200 hz, usin the EQplus settings it still is quite good.

    AM use is limited to our "green" stuff and army nets and am nets here a few times a week on 160/80.
     

Share This Page

  • About Us

    The WorldwideDX Radio Forum was originally established in 2001. We pride ourselves on welcoming Radio Hobby enthusiasts of all types, while offering unbiased, informative, and friendly discussion among the members. We are working every day to make sure our community is the best Radio Hobbyist's site.
  • Like us on Facebook

  • Premium VIP Member

    The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. Care to buy us a beer? We'd really appreciate it!

    Donate to us!