Yaesu FT-901

Why on earth would someone still keep (and use!) a 30-year old, bulky, heavy ‘boat anchor’ transceiver? Good memories? Good performance? A bit of both.

Yaesu FT-901

My FT-901 -still shiny, no damage, and technically 100%.

Building on the success of the FT-101 line, the FT-901DM was crafted as a “hybrid” transceiver, using all solid state design except for the driver and final amplifier stages. It utilized plug-in circuit boards, popular in the 101 and 301 lines, and it featured a die-cast front panel and spectacular solid mechanical construction inside the case. The FT-901 was among the “cleanest” internal structures Yaesu ever created.

The “breakthrough” feature of the FT-901DM was its memory system. In a day when the only concept of “memory” was a quartz crystal, the FT -901DM allowed the operator to push a button, wait about five seconds, and in that time the synthesizer would lock in on the current operating frequency, storing it for later recall. No other HF radio in the Ham world had memory, and it was a huge performance breakthrough that set the stage for the memory-based transceivers of today.

Another area where the FT-901 shone was in its improved receiver performance. The 901 was the result of a concerted effort by Yaesu’s top receiver people, who included a permeability-tuned RF preselector (similar in concept to the “µ-Tuning” modules in today’s FTdx9000!), and the entire receiver section featured at least 10 dB more dynamic range than any previous solid-state receiver from Yaesu. At the time, the dynamic range of the FT-901DM was, by far, the best in the industry, and it led to the wide acceptance of this model in DX and contest circles.

For the fun of it: take a look at the receiver tests, done by Sherwood Engineering (link). Even after 30 years, the FT-901 is still ranking #12 – defeating numerous modern transceivers with ease.

On the transmitter side, the 901 used a pair of 6146B tubes in the final, and utilized RF negative feedback to ensure low IMD products. The 901 series was always renowned for its outstanding audio quality and signal purity. Will I ever sell my FT-901? No way.


24 comments on “Yaesu FT-901

  1. I have a 901 and really like it———–EXCEPT——-

    it requires a fairly closely matched antenna or it shuts down any RF output. I haven’t discovered any way to get it to put out a signal long enough to use an antenna tuner with a longwire or other unmatched antenna.

    Other than that, great rig!

  2. I never encountered that problem, I just have to try that once. As a rule, I want all my antennas to be reasonably resonant (SWR < 1:1.5). I have a 1:9 balun somewhere and a piece of wire; I will test it one of these days.

  3. One of the first transceivers I ever used (24 years ago when working out of VE8RCS) and was a breeze to use as a (relatively) inexperienced ham.

  4. PD0AC de W3TWX/IN3TWX

    Dear Hans,

    I like your web page. In fact, I moved over to the US (Vermont) and am mainly active on 2m EME but managed to install a 15m secondary tower with a HyGain tribander that has ideal matching.

    My own FT901 is here now, and togethe with my SB220 it awaits conversion to 117V. I tried a step-up transformer and noted that (because of the 60Hz???) the display does not work properly but “switches” on and off.

    Q: Any suggestion on how to convert the FT901 from 220 to 110/117V??

    Bedaankt, tot siens


    • Hi Wolf,

      can’t you adapt the internal transformer? My FT-901 can be wired in different ways (110V, 220V, 240V)

      Best regards,


  5. Hans,

    Thanks! I’ll try to do that. Hope it works with the led display too, that one did not work with the 60Hz and step-up transformer, but I’ll look into that. In the worst case I’ll rely on the analog one. I know that later versions of the FT901 (mine was bought in 1980) had a different freq display.

    73 Wolf

  6. hola,tengo una ft 901 dm ,y no se usarla,necesito ayuda ,ademas tiene problemas en su display ,abrazos

  7. hans can you help me please i do hope you can?
    i have lost the lead to my ft 901 dm do you know the pin numbers so i can make up a lead for my radio.
    live pin number?
    neg pin number?
    earth pin number?

    this vradio is 240 volts ireland

    i hope you can help me please

    best regards my friend

  8. I recently became the owner of a ft-901de with no receive.However it dose have plenty of audio… One thing I noticed is when I make contact with the center conductor of the female 259 connector I here not even static when when I put a piece of copper in the center conductor…Do you have any advice this radio is to nice and clean to give up on…Thanks for being there,,,,form john roberts KD0GKM Joplin, Missouri…USA.

  9. Hi John,

    the first thing I would look into are the relays. Being a mechanical component, they will either stop functioning, or (easier to fix) suffer from dirty contacts. It is the most common failure.

    There’s also an antenna fuse, which might be blown out by statics of some kind. You can’t miss it, it’s somewhere in the middle when you remove the top cover.

    If not – there are too many possible defects to discuss them all, so I’ll stick to the most common one: electrolytic condensers. They have a limited life span, especially when they’re not used for a long time. The small ones are cheap and easy to replace. In many cases you can recognise a dead one, because they’re ‘blown up’ (rounded or exploded top). When in doubt,remove them and use your AVO meter to check them out.

    One advice: if you manage to repair the receiver, please replace the 2 electrolytic condensers in the final stage (100 uF / 500 volt), defective or not. If these blow – and you can count on it that they will – the secondary damage will be extensive.

    Good luck,

    Hans / PD0AC

  10. Thanks so much Hans I will keep you informed and up date you from to time.. This will be a great project while Im studying for my general class ticket.. Again Thanks and GOD Bless YOU john..

  11. Well Hans it was the receiver fuse. I put in the new 1/4 amp fuse and she lit up like a Christmas tree…Next will be the big caps.. I will be back soon. Again Thanks…

  12. Hans, I have a new problem. Last night I was listening to the 160 meter band when it seemed like my 901 has a mind of its own. While the band selector is on 160 meter band it jumps up to 80 meters without the selector being touched.. Thanks again Hans jr…

  13. I am buying a 901md…But it does not transmit.

    What are the possible causes ect…I work in electronics and i am a radio amateur.

    Thank you..G6LJX

  14. Hi Simon,

    too many possible causes…. sorry. It might sound silly, but the most common cause is when a new owner forgets to switch on the heater.

    Without the heater on, the only thing happening is applying 6.3 volts to the tubes (see it as a kind of standby mode).


  15. Hi Hans….I am also looking to recap the radio and do you know where I can find the high voltage ones in belgium…?


  16. Hi Simon,

    You can buy them on eBay. A seller called JustRadios sells them in lots of 5. Search for object# 310284826324. Just resell the remaining three 🙂

  17. Cheers again for the good tips..I asked my local radio ham shop about the availability of the tubes..They say you can’t find them now.

    Can this be true..?


  18. 6146B tubes are still made in China. Some sellers even offer brand new matched pairs, amongst them UK sellers. Example: eBay item 370351391684.

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