#199

[@turbo2ltr]

For anyone attempting this: 1: Get yourself a big soldering iron. I bought a 100W chisel tip iron off amazon for like $20 and it worked great . There was no way my weller station was going to do this. The biggest issue is you have to unsolder the antenna connector to get the board out. (and you also have to solder it back in)... The iron made this a breeze. 2: When you get the final switched out, make sure you put it all back together before testing.. I tested it before I put the screws and the copper shield back in and while it was better than it was before, it would not put out full power. I assumed there was something still wrong but when I put everything back together I got full power out. 3: The fan on mine was making some noise, so I replaced it. And I added an 80MM fan to the top. Looks ugly but should help keep it a little cooler. Thanks for this video and the other one on the 400. It really helped testing mine. I also learned I should have bought a 500mhz scope. lol

[@danadkin8652]

I know this video is over a year old but thank you for posting it. I have 2 Ftm400DE's ( early serial numbers) both went wrong twice under warranty then again both out of warranty. I dont run on full power and i check the antenna, coax, connectors and swr regularly. ( and changed the ground plane , the car!) However when the last failure happened i decided to follow this video and give it a go. I used Chip Quick and i added the holes but as my bench drill is not up to the job the holes did not line up in the rows so i filled them out to make slots. This was mu first every repair of a transceiver and it worked. Thanks once again!

[@MrBanzoid]

Another great diagnostic video. Those schematics are scary! I used to think that a superhet receiver was complicated but these are in a different universe..........

[@TRXLab]

Thank you ! Yeah all this schematics can be really confusing....

[@mikesradiorepair]

Good troubleshooting Peter. I agree only using 1/2 of the amplifier is probably going to drastically change the impedance between the driver and final. Will probably end up killing the driver in a short time. Think you forgot to mention you had a 10db attenuator before your power meter.

[@TRXLab]

Thanks Mike! Yeah I fully agree will see when it is back :-) You are right forgotten to mention the 10dB power attenuator.. 73

[@TheRadioShop]

I missed this video. Notifications not working again. Great diagnostic as always Peter. Ashame he did not want to spend the money to fix it correctly though but that is the way things go at time.

[@TRXLab]

No worry my friend we all know that sometimes there are bugs and sometimes time is too short which is my problem currently...Thanks for stepping in 73

[@danilo1782]

Thank you for this nice video, I'm enjoying all the other videos on the channel. I'm just wondering if the volt meter has a built-in rf filter to read the dc bias voltage on the final's gate during tx or I missed something about it. Thank you and 73!

[@iw0hex]

Compliments Peter. I repaired an FTM400 but in my case it was driver RD07MVS2 faulty. Best 73 my friends. Pasquale IW0HEX

[@TRXLab]

Ah that is very intering Pasquale. Can't remember that I have ever found the driver to be faulty in this radio..Thanks for stepping in my friend! 73

[@thuff3207]

Great troubleshooting and it will help me with a friend that as a similar issue with his FTM-400. Thank you!

[@TRXLab]

Thanks for feed back

[@curtw8827]

Great video. Peter, your time is worth more than the part. What a shame the owner didn't have you fix it. 73

[@TRXLab]

The problem with those radios is they die much to often that can be rally frustrating. 73

[@chrisstorm7704]

I recall watching the original video where this radio was repaired the first time. Same fault with one bad FET. I was really hoping to see a few tests to see what would happen if the radio was operated with the gate to the bad FET lifted. Now we see the same radio back a couple years later and I did get to see that after all. If the FETs were in separate packages, would it make sense to only change one of them, or should they only be changed in pairs.

[@w.rustylane5650]

Pairs!

[@maxastuto]

during an alignment of the FTM400XD radio in the TX power alignment parameter of the service manual, started as per procedure from 440.050 Mhz low power and 5.3 watts, I continued up to medium power 20W. By storing the 5.3 watt parameter in the Adj 02 PWR menu with the Adj 02 DVR parameter with 9AH in low power and the medium power parameter Adj 02 PWR with 20W and confirmed with Adj 02 DVR with B0H. When I reached high power (50 watts), while I was rotating the dial to align the 50 watts, the Wattmeter with the built-in laboratory dummy load burned out. Now I don't have a tool to align and verify all 3 parameters, especially the high power one which stopped at E1A when the wattmeter burned out. On VHF I obviously didn't continue to set anything. Can you tell me the alphanumeric codes (e.g. 55H 92H E1a etc which are factory set in the respective power parameters 5 - 20 - 50 watts in UHF in the service menu? I would like to set it with those factory values since I don't have a Watt rf instrument from measure at the moment.

[@teunaydin]

What a crazy test monitors and devices you have ı am more interested on them than radio very nice thank you to show up all this valuable data and knowladge 73 s from istanbul

[@Elektronik-1]

Du prüfst ja immer die Verzerrungen mit 1Khz. Bei Funkgeräte wird dessen 3.Oberwelle, die ja oft stärker als die 2. ist, nicht mehr übertragen. Wäre es da nicht besser 800Hz zum Testen zu verwenden?

[@OleF112]

Das Gerät arbeitet in FM.

[@Elektronik-1]

@@OleF112 FM...ok, das hab ich nicht bedacht. Gibt's da auch ne Angabe bis zu welcher Frequenz die Stimme übertragen wird? Klingt das dann hörbar besser? Bei SSB gehts doch nur bis 2,7Khz!?

[@OleF112]

@@Elektronik-1 Das hängt unmittelbar mit der zulässigen Kanalbandbreite, der NF-Bandbreite und dem FM-Hub zusammen. Schön erklärt hier: www.dl7maj.de/Modulationsarten.pdf. Peter hat dazu auch ein Video, sofern ich mich erinnere. Eine gute Quelle ist auch immer Mikes Radio Repair. Etwas AM-lastiger (US), aber dafür auch schön am Spektrumanalyzer erklärt!

[@TRXLab]

Im Wesen prüfe ich die das Oberwellenverhalten in der HF Lage hier also bei 145 MHZ. Ohne LPF wären die Oberwellen weit über dem erlaubten Maß. Zwar ist es hier ein FM Gerät wie Olaf schon richtig bemerkt, jedoch auch bei SSB Geräten gilt das Gleiche. Die 1Khz NF wir letzlich in die HF Lage gebracht und unterliegt hier wieder gleichen Bedingungen. Mit der 3. Harmonischen hast Du insofern recht das bei Push-Pull Betrieb im Vergleich zu Single ended der 3. Harmonische größer ist als die 2. Harmonische. Da aber das Inbandfilter in der NF Lage schon die 3 Harmonische bedämpft und weiter diese auch in der HF Lage bedämpft wird ist das nicht entscheident. Bei FM gibt es auch eine Beschneidung der NF, das ist nötig das aus dem Produkt von Hub und NF nicht das Kanalraster überschritten wird. Ansonsten hätten wir das berühmte Splattern im Nachbarkanal. Sehen wir oft bei CB Geräten und neuerlich auch bei Free Net Geräten...

[@Elektronik-1]

Danke für die Antwort. Aber so ganz verstehe ich das nicht: Ein steiler 2,7Khz Filter macht doch aus nem 1Khz Rechteck nen schönen Sinus. Wenn z.B. im Verstärker die Rückkopplung kaputt ist und dadurch der Sinus geclippt wird, dann ist das doch gar nicht erkennbar? Bei 800Hz wäre der Fehler aber hörbar und messbar.

[@davez2989]

Is it worth sending you a radio before it dies? to replace know issues with what ever I get. I'm sort of thinking reliability wise.

[@OleF112]

Good morning Peter! That was surprising! Good work indeed, and the final solution (haha) is maybe not the best, but the most practical way to use the radio until its end. This units are nightmares, and sometimes i think that Yaesu should focus on there traditional playgrounds ;-) Anyway, you did your best to make it work again. And to reply to some comments down below: The decision not to repair this unit is ok. The heatproblems are known on this model, and it was not the first time in service as Peter mentioned. So i guess the owner will use it maybe not as a full duty radio in the future, but as a backup radio to mostly listen and low power local "phone". I would do it the same way and save the money for a new device. 73 de Olaf!

[@TRXLab]

Hi Olaf, well under low power it might work and you are right it is used as back up radio for local "OV" phone...Will try in the future to increase the air stream and to protect the gate better for high surge voltages. We will see if that improves the radio..Have a goof Sunday 73

[@davez2989]

Are there any brands that you never see in the shops because they just work? Do Manufactures improve radios of known issues or do they just keep making it the same way and hope it dies out of warrantee? Oh ... your knowledge is just awesome. You mentioned something about a white DOT on the board and using it to count can you give some more info on that? where and how did you pickup your vast knowledge, I like electronics and I know what I would want to learn in school now.. 20 + years late LOL

[@Goyotero1000]

Failing Yaesu fusion repeaters use two of these radios back-to-back to form the repeater. This will be helpful in repairs as the duty-cycle seems to be too much for a mobile radio.

[@TRXLab]

Glad that the viceo is helpful to you. Thanks

[@stevejones8665]

Great Diagnosis realy enjoyed following along Peter....Seems a shame after all the effort put in diagnosing the fault for the customer not to pay for the part to be replaced after all it was designed as a linear amp in push pull now sadly it's just push push hi hi. 73s de Steve M0BFM

[@TRXLab]

Well yes but I can understand it as this radio is really not the best. By the way it is not push pull design only two transistors in parallel...Thanks for feed back 73

[@stevejones8665]

@@TRXLab Yes I should have known it was not push pull No transformer hi hi...Not a good idea putting 2 Devices in the one package either, that's just asking for heat dissipation problems. I really like your R and S Comms Test set very nice indeed.

[@noakeswalker]

I just looked up that PA mosfet - between £25 and £50 depending on where you buy - surely it is a false economy not to change it now, before any more damage is done - as you say Peter. What a big mistake by the owner :o(

[@TRXLab]

Yeah you are right it is 25$...Thanks for comment 73

[@richardedwards6772]

I didn't notice if you discovered the actual root cause? Is the end users antenna at a different impedance then the output of the radio causing a high VSWR? It would be good to know.

[@TRXLab]

very often you can't find a root cause but in this case it is most likely heat...

[@oz1jux]

The owner is he the first owner of this FTM-400? Because the is a hidden menu settings to changes all power levels for Low, Mid and High.

[@TRXLab]

As far as I know he is the first owner and he is not the type of guy who is tinkering around with the settings...

[@oz1jux]

Okay that´s good. That is always the trouble if the owner have change the settings in the hidden menu without to write down the default settings.

[@Jay-hr9ci]

@@oz1jux how can I get into the hidden menu?

[@bblod4896]

About 04:40. You say 10 watts but the 3 watt LED is lit up, not the 30 watt. Should that reading be .75 to 1 watt?

[@mikesradiorepair]

You can see it is runnining through a attenuator before it enters the meter.

[@bblod4896]

@@mikesradiorepair Sorry, did not notice that. Guess I have to up my prescription.

[@mikesradiorepair]

@@bblod4896 Think he just forgot to mention it was running through a 10db attenuator.

[@martindowney7915]

Cool video, Peter how mutch does a new final fet cost if your customer didn't want to replace it?

[@TRXLab]

Thanks for watching Martin. The FET is about 25$ 73

[@ntacell11]

wow..another step forward..thanks Peter..do you have anything for very low level on RX for Kenwood Ts-450s. Thanks 👍

[@TRXLab]

Not in particular a 450 but there are some videos here on my channel showing the process on how to approach a RX issue....

[@simonkirby6064]

Does yeasu have a problem with there quality control I have ft891 had 2 months had go back for repair

[@TRXLab]

not in general but from time to time there is a radio with a critical design and sometimes it is bad luck...

[@kevingray707]

Not following the output power. Through the video it looked like the meter was on a 3 watt scale not a 30 watt scale. I am sure I missed something trying to understand the odd type meter. Can elaborate

[@TRXLab]

Yeah as already mentioned here in the threat we have a 10dB power attenuator in front of the device that makes the 3Watt scale 30W...73

[@kevingray707]

Thank you for the follow up as I was so confused. Great stuff once again

[@richardcook4643]

Thanks for another great video Peter. Good info!

[@TRXLab]

Thanks Richard 73

[@scottjacko87]

I have one of these rigs and so far (touch wood) it's working OK. I know if my PA failed i'd go ahead and just replace the finals.

[@TRXLab]

Yes the final heat sink is the problem...Thanks for watching 73

[@dl7majstefan753]

I think we could open a bet how long it takes until this transceiver is back on your bench again with the second half of the PA killed…..

[@etheroar6312]

What's the over/under?

[@TRXLab]

LOL yeah we will see :^) 73

[@alancordwell9759]

My thoughts exactly!

[@orvilnunez2181]

My guess is the owner is planning to replace the fet himself. He probably just needed peter to find the problem. If not we’ll get to see it back on the bench.

[@TRXLab]

That my often happen but not in this case...I know him very well. Thanks for watching Orvil 73

[@Alan2E0KVRKing]

So according to comments no more than £50 plus labour to fix, maybe going to cause more damage in the meantime. I don't understand why he didn't want it fixing??????

[@TRXLab]

The owner is informed about all the risks so it is up to him...

[@baghdadiabdellatif1581]

Great work. Thank you

[@ojjenkins7110]

How much is a new fet?

[@TRXLab]

Hi OJ it is about 25$ 73

[@AECRADIO1]

KENWOOD MOBILES SUFFERED OUTPUT LEVEL CHANGE SIMILAR TO THIS, A REFLOW OF SOLDER CLEARED UP THE ISSUE. THE OUTPUT DROP IN TK-941 WAS BAD SOLDER JOINTS IN HALF OF THE REPAIRS. YOUR MODULE MIGHT BE DEFECTIVE. I AM NOT FAMILIAR WITH THIS MODEL, SO I DO NOT KNOW WHAT RF DEVICE IS USED. I SUSPECT A MOSFET, LIKE AN RD70HVF1 FROM MITSUBISHI. I GUESS I WAS CLOSE ENOUGH. RD70HUF2.

[@robertosborn8720]

What about the UHF side of things, I never saw you test 440 Mhz range. Looking at the input of the final area it looked like there was separate tuning by the size of the coils leading to the 2 sides of the input to the final. Spectral purity might not be as good, nor power output. I know the customer did not want to pay for a new final, but I would never let a radio go out like that myself. 73 N8EFJ

[@stargazer7644]

+Robert Osborn And what would you do if the owner doesn't want to pay to have it fixed? Fix it for free? Disable the transmitter?

[@TRXLab]

Yes that is valid question. It is the property of the operator and by law he can decide...

[@robertosborn8720]

Not familiar with European laws but I would put it back together exactly the way is was and send it back. As a commercial shop employee I have a responsibility to not allow anything on the air that does not perform as it was intended and meet the Production specs. We as a shop are responsible for any work we do and any interference the equipment may cause. The owner can say the shop did the work if they cause RF problems on the band. I am speaking commercial RF transmitters for industry though which is what I do for a living. Hope this explains what I meant with my original comment. The customer can save up and have it fixed at a later date. But not be on the air where he might be causing problems with a reactive load such as an antenna, this will have (or create) different results than a dummy load with a unbalanced RF output FET.

[@stargazer7644]

@@robertosborn8720 Peter checked to make sure the output was within the legal requirements. The concern was that running the rig this way might cause damage to the driver. The customer assumed that risk. I imagine there was no warranty on this repair because of that. I can appreciate your risk when repairing commercial type accepted gear. There is a difference between commercial equipment and ham gear. Every amateur is responsible for his rig meeting emission requirements. That's why hams can legally build and modify their own equipment. At least this is the case in the US.

[@80Loke]

Very good episoder as usuall always Nice to se a new video from you :)

[@TRXLab]

Thank you 73

[@robertcalkjr.8325]

Thanks Peter.

[@TRXLab]

Thanks for stepping in Robert 73

[@jerryblood9554]

Nice radio. I would have had it repaired.

[@stargazer7644]

It isn't a nice radio. I have one. It has issues. And it's a pain in the ass to use.

[@grantfullen9559]

Great Job Peter :)

[@TRXLab]

Thanks Grant! 73

[@fungas4804]

Time for an on-screen Ammeter/Voltmeter project?

[@TRXLab]

or a temperature on screen project ?

[@demorganize]

The power meter looks like it’s on the 3W range not 30W range

[@mikesradiorepair]

He has it running through a attenuator before the meter.

[@stargazer7644]

The radio is supposed to put out 50W, so he has to use an attenuator on a 30W meter. You can see it between the meter and the cable at 2:35. This reduces the power by 10 dB, so the meter is on the 3W scale to read 30W.

[@Beretta96Dan]

Throw it in the trash! We live in a disposable world now, unless your money comes hard, like mine. Sometimes, though, it is more cost effective to just give it away to someone to tinker with.

[@TRXLab]

Hey Dan you are killing my job :^)

[@daveys]

Comes with Yaesu’s traditionally crappy interface (and I have one of these too, so shame on me for buying it then complaining)

[@michaelclutton8446]

How strange that you have to do the work, then he doesn’t want to pay the extra to complete the repair

[@TRXLab]

LOL yeah that is how things go : -)

[@jonka1]

Having run a general repair business for most of my life, nothing surprises me (well almost nothing) when spending money is concerned.

[@johndk9jc354]

LOL nice experiment :-) 73

[@TRXLab]

LOL of course we love to experiment 73

[@bobkozlarekwa2sqq59]

The meter on your power meter needs to be adjusted, zero adjust is off slightly.

[@Alberto_Alletto]

when do you make a new video?