I am amazed you managed to find the fault so quickly on a complex device without any documentation. Well done.
@LiraLab3 жыл бұрын
If videos like these do not encourage people into electronics and RF, I don't know what would do. Your ability to trace down the fault is no joke! Thanks a lot for these educational repair videos!
@w2aew3 жыл бұрын
Whoa - that X-ray machine is new, huh? Nice debug and repair...
@Thesignalpath3 жыл бұрын
Hi Alan! No, I have had it for several years. :)
@AndrewZonenberg3 жыл бұрын
Nice to see my probe getting some use! I'll send you some pogo tips for it which should improve the landing quality. I can send you one or two of the solder-in sibling, the AKL-PT2, too.
@Thesignalpath3 жыл бұрын
Thanks! Improvement to the tips would be hugely welcome!
@BaconbuttywithCheese3 жыл бұрын
Will the AKL-PT1 be back on sale at some point?
@AndrewZonenberg3 жыл бұрын
@@BaconbuttywithCheese It never was sold openly in this form. I did a kickstarter for the 2.5 GHz first revision then massively improved it to the 6 GHz bandwidth prototype Shahriar is using. I'm still making slight tweaks to improve flatness and ergonomics before a full launch. Its solder-in flex sibling, the AKL-PT2, is available now.
@thomasw61693 жыл бұрын
Very good find. The excellent knowledge is the key to locating the spot. Without you have no chance cornering the cap. Brilliant !
@sirousmohseni43 жыл бұрын
I lear alot from your thought process when you tackle a faulty device. Much appreciated.
@trickyrat4833 жыл бұрын
You know, at the start of this video when you stated "no, it's not a front panel connector issue" I jokingly said to myself, "ah, probably needs a recap then!" Sorry, too many Mr Carlson old radio videos in my system. :)
@maurosobreira86953 жыл бұрын
When the failure comes to passive element in such a complex circuit and you can track it and fix it...nobody can say you cheated the exam on the front panel connector😉
@campbellmorrison85403 жыл бұрын
Wow impressive. I love watching your video's even though sometimes your discussion goes over my head. Wonderful analysis to watch
@jeanaimarre86053 жыл бұрын
Amazing. Few minutes, without manuals, and voilà. Unbelievable.
@leocelente3 жыл бұрын
Nice to see the detective work, going from the resistor voltage drop to the capacitor causing the resistor to fail.
@bfrost9993 жыл бұрын
Absolutely excellent diagnostics. Fascinating for an electronic engineer here who only ever built low band stuff.
@jimomertz3 жыл бұрын
Awesome diagnosis and repair. I wouldn’t know where to start. You still got lucky that it wasn’t one of those custom IC’s that failed. 😺
@SeanBZA3 жыл бұрын
IC's tend to be reliable now, as the early failure modes were researched and understood, and fixes applied to the process path for the more reputable manufacturers. The cheap ones know how they will fail, and roughly how long that will take, so just build good enough, to last that long for the vast majority of the devices. I would say R&S, and most of the other top end manufacturers, know the equipment might be in use for decades, so go for the most reliable IC's in there, and good quality for the rest as well.
@e2jw3 жыл бұрын
Excellent job methodically trouble-shooting this fault and repairing it!
@skylabby3 жыл бұрын
you make this looks so easy...thanks for the video
@gregorymccoy67972 жыл бұрын
Superb reasoning. Pretty sure I would have been lost. Reverse engineering a complex board looks easy when you're doing it.
@VitorMartinsAugusto3 жыл бұрын
As usual, great video! I have one question, though: isn't the noise floor quite high at -50dBm? I would expect at least -80dBm from an R&S Spectrum Analyzer. Even the "TinySA" has about -80dBM noise floor!
@funtv3291 Жыл бұрын
Hi! I think, it's because the reference level is 9dBm (it's too much for preciece measurements) and large RBW (3MHz). Or maybe cheap 5% accuracy capacitor... Who knows😀
@electropatagonico3 жыл бұрын
really nice analysis! to find that tiny cap. Great job and very interesting to see all the process.
@octavmandru92193 жыл бұрын
I believe these decoupling capacitors shorts are the main culprit for many PC boards malfunctions.
@drulli13 жыл бұрын
Awesome, as always. You are the HF Master!
@qzorn44403 жыл бұрын
o-my... i really thought that when you looked under the R&S hood there would be an arduino hanging on cable-ties...:/ this is so exciting, let the show go-on...:) thanks smart guy..
@baghdadiabdellatif15813 жыл бұрын
Great work 👌 So the bypass capacitor developed a partial short?
@douro203 жыл бұрын
I was actually hoping to see another early-'90s one with Transputers...but people tend to hold on to those things due to their performance being so good.
@IsaacBentley3 жыл бұрын
I have a R&S VNA with the transputers, it’s pretty great. But I never knew that people wanted them.
@bfx81853 жыл бұрын
Really nice repair with excellent explanation! Thank you!!!
@stevenbacon38783 жыл бұрын
Great video as always!
@rowifi3 жыл бұрын
Where did the analyser come from, what did it cost to buy as a broken unit?
@DrFrank-xj9bc3 жыл бұрын
A common fault of MLCC: cracks which produce a short. commonly on MLCCs with higher number of layers, i.e. high capacitance. That one looked like a fat one.
@aqib20003 жыл бұрын
I find these all the time
@PileOfEmptyTapes3 жыл бұрын
MLCCs will crack easily if heated unevenly, and silver migration through the cracks courtesy of lead-free solder will ultimately do the rest (note the Pb-free symbol on the board). An unholy combination. To think that an instrument like this (few things R&S are ever cheap) can be taken out by a single bad one like ordinary consumer electronics is wild. I hope R&S have at least considered going with automotive grade MLCCs in more recent times. This model appears to be from the mid-late 2000s.
@lordjaashin3 жыл бұрын
@@LordPrecision but all this eco-posturing makes purple dyed hair people feel superior about themselves
@jessiepooch2 жыл бұрын
Eco-posturing? Pathetic.
@Nermash3 жыл бұрын
Outstanding repair, as always :)
@steveoffer29173 жыл бұрын
How far is that cap from the shield fixing screw? If it's pretty close then root cause is a design error; too much stress on an MLCC. Awesome repair video, outstanding presenter.
@deeeppurple3 жыл бұрын
I have seen this a few times when caps close to mount hole would crack due to mechanical stress.
@madinatore3 жыл бұрын
did you actually record this video less than 48h ago and already did all the editing?
@Thesignalpath3 жыл бұрын
I do almost no editing at all. It is just recorded sequentially and stitched together. I normally don't spend more than 20 minutes on editing.
@tommihommi13 жыл бұрын
so it's almost a recorded talk
@vovamonte37663 жыл бұрын
Hello! Very interested in your X-ray machine! can you provide x-ray information as your device is called?
@TheDefpom3 жыл бұрын
Nice reverse engineering and fault diagnosis, it is surprising how many times a fault comes back to a bad ceramic capacitor.
@Novous3 жыл бұрын
>googles price of Rohde & Schwarz "Oh... okay... so it's worth more than my car. So that's something I'll never own in a million years."
@Henning_Rech3 жыл бұрын
FSL is from the low cost (low performance) series.
@MicrosiMe3 жыл бұрын
The PCB of magic
@RyanUptonInnovator3 жыл бұрын
Great video
@electronics_engine6 ай бұрын
I have spectrum analyzer has fault sometime show LO unlock, I can open transit case to check main board, please show me hownto open it?
@AECRADIO12 жыл бұрын
So often a defective cap or resistor causes the unexpected failure. Nickel barriers are a huge issue, poor solder ability at times, or they magically debond and create high resistance.
@99.99.93 жыл бұрын
"We probably won't even be able to find the data sheet for them" *Louis Rossman has entered the chat*
@Thesignalpath3 жыл бұрын
Haha... Only if it were as easy to get this schematics as it is to get an Apple laptop schematic.
@Dfk429S9fo33 жыл бұрын
@@Thesignalpath you mean Paul Daniels doesn't have board view software for that? :)
@gordonwedman31793 жыл бұрын
"Unsurprisingly it passes it's self test". Well of course, as the Master has laid his hands upon the instrument. Another unit rendered inoperative by a few cents worth of parts. Unbelievable 🤔
@CoolMusicToMyEars3 жыл бұрын
Great repair 👍
@gacherumburu99582 жыл бұрын
👍👍
@younesthabet3 жыл бұрын
me as a junior embedded systems engineer watching this video thinking to my self "what got me into this!! probably i will never be this good"
@labiadh_chokri3 жыл бұрын
Thanks for this video , you didn't use thermal camera to tell us that with basic tools we can do a repair.
@funtechu3 жыл бұрын
I love a great $0.008 repair.
@video99couk3 жыл бұрын
I feel hard done by if I have to fix a Betamax video recorder without a schematic, and you fix a spectrum analyzer!
@andymouse3 жыл бұрын
Fascinating stuff...cheers.
@mustaphacherkaoui9703 жыл бұрын
bonne représentation et explication fort analyseur
@rogeronslow14983 жыл бұрын
Nice repair. I just wonder why the noise floor is so high. It's around -35 dBm at 6GHz.
@nilsalbrechtna3 жыл бұрын
3 MHz of RBW and a fairly high reference level with 30dB frontend attenuation increases the noisefloor quite a bit. Additionally this SA might not be the lowest noise instrument
@Henning_Rech3 жыл бұрын
It is from the entry line series. Low performance, low cost.
@Justplast3 жыл бұрын
A1 Mate very nice
@tocsa120ls3 жыл бұрын
9:00 X-ray that only stings once? ;D
@thanhnguyentien36423 жыл бұрын
Hello, Can you calibrate CMW500?
@FixDaily3 жыл бұрын
Why some traces that connect resistors\capacitors or inductors don't have solder mask?
@Thesignalpath3 жыл бұрын
These are the RF traces. Solder mask is a poor dielectric material and is often avoided on RF paths. It is also generally not included in the EM simulations.
@FixDaily3 жыл бұрын
@@Thesignalpath Thanks. Can you explain more about this "Solder mask is a poor dielectric material"?
@danielrezu62013 жыл бұрын
Super
@shazam62743 жыл бұрын
Repair of defective R&S FSL Spectrum Analyzer: 1) remove covers, 2) remove PCBA 3) analyze circuit 4) find defective parts 5) replace parts. Equipment required: 1) X-Ray, 2) VNA 3) special probe (fund on Kickstarter) 4) soldering iron, solder wick, hand tools, etc. Or buy a new one from Siglent; >$100,000 test eqpt. not required :) Great stuff Shahriar. I always learn a lot from your videos and am a big fan. Thank you.
@Thesignalpath3 жыл бұрын
A narrow vision... en.wikipedia.org/wiki/Electronic_waste
@PeregrineBF3 жыл бұрын
@@Thesignalpath Yep. And if right-to-repair legislation makes providing schematics (and hopefully layout) mandatory the X-Ray could be skipped.
@shazam62743 жыл бұрын
@@Thesignalpath You should send this to R&S. No schematics, no manuals, no parts. Pure arrogance creating land fills of dead R&S products.
@SeanBZA3 жыл бұрын
@@Thesignalpath Repair and Reuse, Shariar is doing his utmost to get the last one, Recycle, out of common use, as repair and reuse is the most use of the rare elements that were used, and gives the lowest impact on the environment as well. That he also gets some impressive use out of them is also a bonus. Then of course the equipment that is tossed for an utterly trivial fault is the best value as well.
@Thesignalpath3 жыл бұрын
@@shazam6274 First of all, R&S does not perform component level repair. No big T&M company does. The board would be tossed out and replaced. We are not even taking into account the cost of shipping and repairing it. Aside from that, it represents an opportunity to offer education on top of the repair benefit.
@davyjourdain2000 Жыл бұрын
Hello, your work is fabulous, well done. I would like to ask you for advice because I have a Rhode&Schwarz FSL3 and the tracking output on the spectrum analyzer is defective. I don't have any schematics or electronic plans. My problem is the following: from the tracking I output a 0dbm, then from 9khz to around 100khz the tracking is not good at all. After 100kz it is at -2.5dbm up to 1ghz and tends towards 0dbm very slowly up to the max frequency 3ghz. Can you help me please ? THANKS
@esepecesito3 жыл бұрын
Amazing how a 1 cent part can ruin such expensive equipment
@stevec50003 жыл бұрын
Too bad those probes are not available! They only have available a Passive Solder-In Probe which is just an expensive piece of transmission line, the others are still vaporware!
@ErZocktLP3 жыл бұрын
Daily driving such a FSL :)
@AL6S007403 жыл бұрын
From where do you even buy these?
@Thesignalpath3 жыл бұрын
eBay!
@RayRGK3 жыл бұрын
@@Thesignalpath What do you do with repaired units? Do you sell them back?
@GeorgeTsiros3 жыл бұрын
What is the I-V characteristic of a catode?
@christophbrand3 жыл бұрын
Almost all physical processes, but especially all electrical characteristics of semiconductors (diodes, transistors and similar components) or vacuum tubes, are "non-linear". That means, linear change of a parameter, e.g. applied voltage or resulting current do not show a linear, uniform change of the corresponding result. In order to represent this optimally, these values are graphically displayed in curve form in a so-called "4 - quadrant characteristic curve field" - "The I-V Characteristic Curve". This enables the simultaneous representation of 4 characteristic curves, in 4, horizontally and vertically adjacent fields, registered on a +x -x +y -y axis cross (Field number: I - V), with change of their values (voltage, current, resistance etc.). Sources: (Excellent) translation program : www.deepl.com/translator duckduckgo.com/?q=4+quadrant+characteristic+transistor&t=ffsb&atb=v96-1&ia=web fytronix.com/PHYSIC-EQUIPMENTS/Characteristic-curves-of-semiconductors-PHY2013.pdf www.sciencedirect.com/science/article/abs/pii/S0042207X19304555 duckduckgo.com/?q=4+quadranten+kennlinienfeld+transistor&t=ffsb&atb=v96-1&ia=web duckduckgo.com/?q=4+quadrant+characteristic+transistor&t=ffsb&atb=v96-1&iax=images&ia=images duckduckgo.com/?t=ffcm&q=the+I-V+characteristic+of+a+catode&atb=v96-1&ia=web Greetings ... :)
@GeorgeTsiros3 жыл бұрын
@@christophbrand i feel bad now, because I was making a joke... i know what I-V characteristics are and I know what cathodes are but not what CATodes are...
@christophbrand3 жыл бұрын
@@GeorgeTsiros Hmm ... ok... well... I'm not angry with you. I hope you had at least a little bit of fun, otherwise it would have been all for nothing. Well, it was also a little bit fun for me too, rummage in old memories of my education, which are already a little bit "dusty". ... ... ... I think, the way you meant it is probably the ode (poem form) to a cat was meant ... oh what ... is also no matter. You have led me, once again, clearly in mind, in any situation not to lose the "view of the whole", and at least to keep the/my humor. For me, humor, fun and jokes are a very unique and (and especially related to the "present time" ... an over-) vital essence of life itself. It helps reliably to get over "bad times", and I had more than enough of them in this life .... With kind regards christoph
@GeorgeTsiros3 жыл бұрын
@@christophbrand look, _i_ may not needed your explanation, but others quite certainly do! Your effort was absolutely worth it, because anyone here can read it and get some information!
@davidsweeney1113 жыл бұрын
Your into- and outro- music is cool, I guessing you play electric guitar lol?
@aaaaa-yv1zr3 жыл бұрын
Seems like component problem. But R&S may charge you $3000 for repairing.
@SeanBZA3 жыл бұрын
No, they will simply swap the board with a new one, and charge you $15k for that, and extra for the calibration afterwards.
@s9212073 жыл бұрын
@@SeanBZA EXACTLY what happened on my RTO scope. Two channels just dead suddenly one day (seems like communication problem between front end board and main board). They swapped the main board and calibrate, which costs $6,000! I still don't know why it's broken or even maybe no hardware is broken?
@tommihommi13 жыл бұрын
now the question is, would it be more or less expensive than 6k to pay an engineer to actually find the fault, fix it, and verify everything to a level that you're confident in the fix as a company?
@digitalradiohacker3 жыл бұрын
@@tommihommi1 Why employ engineers full-time when you can short-term contract them to do the initial design, and then vanish them with a draconian NDA in their back pocket? All of these companies are the same now - They have impressive research departments, but are mostly just marketing companies that hire the odd bit of part-time talent from time to time. Compare the above to a robot in China spitting these boards out at 10 per second.
@tommihommi13 жыл бұрын
@@digitalradiohacker the engineers are busy designing the next generation, from what I know Rohde Germany is a decent employer
@GeorgeTsiros3 жыл бұрын
Okay so, two years ago, i let a cat stay at my place. My troubleshooting skills did not improve at all. I come to the conclusion that it is not the cat.
@rowanlidbury3 жыл бұрын
It honestly feels like you're rushing through these videos recently, you're hardly giving yourself a chance to take breathe.
@Thesignalpath3 жыл бұрын
Limited time to record.
@xDevscom_EE3 жыл бұрын
№2 ))
@Ricard2k3 жыл бұрын
When ypu speak everything seems easy. XD
@tenmillionvolts3 жыл бұрын
Whenever I have an RF fault in something, I imagine an awesome rack of high frequency test gear, and how I could work through the RF stages . Then I look down at my old 40Mhz scope and realise, this isn't going to go well :-(
@xxdavidpxx3 жыл бұрын
#1
@chabtiparan3 жыл бұрын
ora mudeng bahas opo
@mc_cpu3 жыл бұрын
10cents of parts bring it down
@lapochaii91523 жыл бұрын
hi thanks for posting your knowledge !!! Could you activate subtitles in Spanish ??? I am a follower of your videos, from Argentina !!! Spanish subtitles??
@Thesignalpath3 жыл бұрын
I have enabled the Auto Caption. Hopefully you can set it to any language now.
@jxlin96803 жыл бұрын
very expensive...
@ddlc70223 жыл бұрын
You have good RF knowledge, but your pace and your voice make it difficult for me to watch the video.
@Thesignalpath3 жыл бұрын
I am sorry. But it is a matter of lack of time.
@Microwave_Dave3 жыл бұрын
KZbin has a playback speed feature. Watching at 0.75x or 0.5x speed may help.