My Yaesu FTM-400 is not working and has the blues!!

My Yaesu FTM-400 is not working and has the blues!!

Overview

Moonraker’s Jez M0RNX talks FTM-400 blues ... some magic smoke and a blank screen!

To repair or not to repair that it is the question!?

Background

I have three FTM 400 XDE transceivers, two make up an analogue and digital Wires-X node ( I would agree an FTM100 would do admirably for a node - have that too ) and one remains independent in the car for my use on the repeaters.

I still love the analogue repeaters on 2m & 70cm and can be found trundling along to & from work on HR, TU, LT and NP.

Although that is not an exhaustive list of all the available repeaters on my journey, take a look as we really are spoilt.

Jeff, my colleague, uses his for C4FM and the fusion network that has gotten very popular of late.

Really do try all of it and even if you feel you’re just heating the clouds by calling some days, persist.

None were new radios, all second hand from reputable dealers and I myself have had them a number of years. One niggle with the FTM 400 is the audio output and the requirement for the adapter, so easy to blow the final by getting that wrong.

So there I am trundling along and the screen goes dark, also smelt some magic smoke escaping, but it did light up and in true form I just carried on. Twice more and it finally did go dark permanently. Although I checked all the ‘in car’ circuitry, the only clue was a blown 15 amp fuse.

Known unknowns

  • As already mentioned the audio output being unhappy with the wrong external speaker connection.
  • Overheating the finals at full power by inadequate ventilation. Or judicious use of an external accessory fan.
  • A short caused closer to the radio by poor installation, wear or fatigue.
  • A short caused at the antenna. Salt & water ingress at any one of the joints during the bad weather. Karl at Yaesu Uk was very helpful with this pearl of wisdom. Seal everything as the dirt & corrosion is dreadful.

    On inspection

    No smell or visible damage in the body of the radio except the shorted and destroyed diodes on the circuit protector.

    The big question for a now obsoleted transceiver, was it worth sending in for proper inspection & repair. Were or are components readily available and was it cost effective.

    Let’s face it, the FTM 400 has a delightful display and although digital on only one of the receivers, has a finger friendly touch screen and although speculative (as we don’t know yet about the FTM 500 ) the last of the big easy read displays. Images of bodged magnifiers in front of titchy screens abound.

    A quick shout out to Karl at Yaesu UK and off it went to the hospital. Just over a week later and diagnosis was in, a dry solder joint in the head unit. I didn’t expect that.

    Conclusion

    Honestly, I did um & ah about sending the radio for repair, out of warranty and now obsolete and with questionable parts availability, I could have just recklessly consigned it to the junk bin.

    The radio out of commission was more disturbing than I thought it was going to be, the head unit sits to my left on a ram mount and I found out my hand went to it almost as often as I changed gears, it was that used.

    Quick note on the RAM mount as I diligently reamed and tapped the thread slightly larger to take a RAM camera mount 1” ball.

    Ashamedly I don’t have the confidence to tackle surface mount without enough glass to weigh my head forward, nor the dexterity to wield a soldering iron capable of such athleticism. Note to self, at least a greater understanding or ability to read a circuit diagram is desirable and although I’ve got the basics, more practice would be good.

    It is a technical hobby and I am an inveterate tinkerer and builder. Shrugging your shoulders and not at least doing some homework before asking an expert is desirable, if not just to understand what is explained to you.

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