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FT-991 MARS mod?


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!
 
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!

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.
 
Last edited:
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.
 
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.
 
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.
i redid the jumper on jp3 and it is working fine.
 
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.
 
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I need help again masters, is there an MARS mod for the FT-991? Thanks in advance.
yea it really hard. have to pull off the front. best get some one to do it for you there r videos on YouTube but it lot just to get to the chip that has to come off. its behind the display
 

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