Besides a lightning strike what else can caused a mossfet to go bad?
@drewman9027 ай бұрын
I'm one of the 3 people that would like to see how you replaced the RD70HUP2. I'm planning on making the attempt myself.
@JuliansRandomProject6 ай бұрын
You got it! I'll record the next one that comes through the shop. I have a hot air rework wand that I used to heat the chassis to ~650f. Desolder and lift all legs first then apply heat under part until the solder melt and lift (or drop if you're using gravity. Good luck!
@drewman9026 ай бұрын
@@JuliansRandomProject Thank you!
@drewman9025 күн бұрын
@@JuliansRandomProject Hey, Thanks again for this video. I'm returning here as I removed the RD70HUP2 from my radio last night. It went exactly as you said. I used hot air and gravity to let the plate just fall off the board. Everything went smoothly. Question for you - After replacing the RD70HUP2, did you need to do any of the alignment steps from the technical supplement manual? Specifically, the Drive Stage Idling Current Adjustment?
@kc0ofz11 ай бұрын
While my mosfet does not look burnt I do not have any power output on any band. I am leaning towards this as being the issue. Not sure if this is a repair, I am able to do or not. Will have to decide, I guess.
@JuliansRandomProject10 ай бұрын
You’re welcome to ship it in to me for the repairs. Message me on Instagram
@jessies9081 Жыл бұрын
I replaced the MOSFET on my FT-400xd because I had the common low power output. When set to 50W, it would xmit about 19W. The MOSFET was a challenging repair, but went smoothly. I was getting the full 50W across most of the bands. But... My dumbass decided to do the MARS CAP mod, AND.. a firmware update. It worked like a champ for about a week, but then it started changing freqs randomly, and intermittently powering off. Now it's acting like a brick, and I assume it's from a software perspective. Live and learn I suppose. Great video man.
@JuliansRandomProject Жыл бұрын
Thanks! Can you roll back the firmware? I'd suspect the firmware also.
@vvatc Жыл бұрын
"It is alchemy for Christ's sake!" LOL
@cheuk-yanau428311 ай бұрын
I am also undertaking this repair, but i managed to dislodge the heat dissipator plate from the PCB and now im waiting on the delivery of the new RD70HUP2 mosfet. You reckon i could leave the heat dissipator unsoldered onto the bottom of the mosfet and make kind of a thermal paste heat dissipator sandwich? It would make it easier to work on it in the future.
@JuliansRandomProject10 ай бұрын
I’m confident that the solder will transfer heat better than paste. Put come thermal couples or temps sensors on both sides and monitor it for a while under 10% to 50% and see how it goes.
@valerijsteterjuks8795 Жыл бұрын
Ну и зачем это видео, если сама процедура замены так и не показана? Зря только время потерял на просмотр! 🤨
@JuliansRandomProject Жыл бұрын
Ты прав. В следующий раз постараюсь показать часть ремонта, пусть и в таймлапсе. Печально то, что если я покажу все подробности, нормальные люди уйдут с видео. Вы особенный, они разбираются в деле. В следующий раз я сделаю лучше. В большинстве случаев вы пропустили откручивание множества маленьких винтов и отпайку детали с помощью большого утюга, который легко переносит тепло. Удачи!
@roberthopkins80895 ай бұрын
So power mosfet has cooked on one side... I got it apart without issue. Problem was not enough solder on back of chip so the failed end had overheated... It happens My question now is what temprature solder paste to use to replace the new device to board and heat spreader... I have some chipquick 138 degree c but notice the max channel temp on spec sheet is the usual 175... But instructions, say to keep device below 140 which is sensible... Anyone have any experience in this area... Regards Bob
@JuliansRandomProject4 ай бұрын
Bob, I only use chipquick to remove components, then clean and remove all chipquick and apply fresh 63/37 solder. hope that helps.
@tonyj57127 ай бұрын
Beautiful job !!
@igorlevchenkov1439 Жыл бұрын
My transceiver Yaesu FTdx10 had the same problem. After replacing the MOSFET worked for two hours then failed again
@JuliansRandomProject Жыл бұрын
Proper lighting strikes or power surges can often take out supporting circuitry like capacitors, voltage regulators and the like. Message me on Instagram I may be able to help.
@artnascar9748 Жыл бұрын
Julian man that look like a pain-in-the-ass great job. ✌️🇺🇸
@beaseac Жыл бұрын
Nice tune!
@JuliansRandomProject Жыл бұрын
Top of the charts right now :)
@JoseVGavila7 ай бұрын
I am about to do a similar repair (well, there are two of them already waiting for this job on my lab!). I am not sure if I understood how did you replace the MOSFET. Did you take out the bottom heatsink plate, soldered the power transistor legs and then soldered back the heatsink?. Or did you leave the heatsink on place and then heat it until you could solder the transistor from the upper side of the PCB?. Also, how did you sepparate the transistor from the heatsink in first place?. Please, any clarification on the exact procedure would be welcomed. Thanks!
@JuliansRandomProject7 ай бұрын
You’ll need a hot air rework station or a massive soldering iron to get the heat sink up to temp. When removing the part, lift legs first, flip board and heat to remove body of part with gravity and maybe a little help from tweezers. When installing, line up the part, flow heat sink to get to seat then solder legs. Or you can send it in to me. JuliansRadioRepair.com . Godspeed!
@JoseVGavila7 ай бұрын
@@JuliansRandomProject Thnaks for the details!. I am a bit far from you, in Spain. I also work fixing radios since the 90s but as my main work since June 2012. So far, about 5500 rigs have passed through my workbench. I hope to reach 10000 before retirement 😅 The FTdx-10 final replacement is one of the few soldering jobs so far that I am reluctant to get into. But I need to do it. So I am gathering information to plan it carefully. I will report back when I have done it. BTW, I don't recall if you talked about setting BIAS to the transistor, that is a key thing to do in all PA repairs, as you know. Thanks again and keep the good work!
@JeffN4POD9 ай бұрын
You might be surprised... it could very likely be more than 3... LOL!
@evo656 Жыл бұрын
Hi Can you answer insta request? I can't send message if you dont accept chat invitation
@JuliansRandomProject Жыл бұрын
Try again, maybe mention the youtube channel to get past filters?