Had a similar problem on my old Marconi 2019 with on output. Pulled it apart to check output from RF amp all good. Checked at output of attenuator all good. Turned out the sacrificial adapter and DC block had a fractured joint! As soon as I saw your fault I wondered about the output connector. Great job!
Hello Shahriar, I think of you as my brilliant nephew, from a long lost brother. I have been enjoying your skills, oration, and repairs for many years now, and thank you again for the service you gift us in the RUclips audience. You have the ability to give of tips and skills to repair as well one docent all in one. Shahriar, bless you over and over again. Take care of that cool kitty, and that poor girlfriend of your's with the dirty tooth brushes....lol
I’ve repaired these attenuators in the past. There are little quartz/alumina attenuation tiles for each stage and I had one with a hairline crack. Our friends at Keysight provided a new tile and with careful disassembly & re-assembly it was possible to replace it.
Did a similar repair to my 8566 Spec An back when it (and I) were young. HP actually sold those attenuator 'tiles' and I was able to replace the tile and got it all working. Heckuva delicate job, but saved me some bucks as the attenuator assembly was big bucks.
I love the channel and the cat! Absolutely love your work and knowledge, even though I’m not in this field. The troubleshooting and repair videos are awesome!
Yes if you bought a fixer up from eBay this would great . But for a repair video , not as good , but makes point " sacrificial connectors " ;) Thanks again
I tend to suspect that over-tightened sacrificial connectors are the usual mechanism by which this happens though (see Joel Dunsmore's comment). Of course, that's not a reason to avoid sacrificial connectors, just a reason to be extra extra careful when removing the sacrificial connector, because that's the moment of maximum risk.
My cat will chew cables. He can't come in my work area. I liked the repair. It seemed really real-world, that is likely to occur for most people. Great work!
Another REPAIR video, awesome! Upvote first, watch second :) This is going to be an expensive Patreon month but I absolutely think it is worth every $.
Thanks for supporting the channel. I did not charge this video to Patreon, I only posted it there. I only charge some of the my videos to Patreon supporters.
@@Thesignalpath Yes, I know.. very considerate of you. I still think every one would for sure be worthy :) Keep up the awesome work, especially enjoying the repair videos.
That reminds me of the joke about a consultant that goes to a nuclear powerplant for troubleshooting - gets inside the machinery, takes a hammer and hit a nail - everything works fine after - bill 500k USD...after being questioned on why the bill was so high - he goes in the details and present - Hammer the nail - 1 dollar, knowing that the nail was the problem - 499,999 USD...Now I know the guy was Shahriar!
mauro sobreira , A retold story of Momo Motors in NYC... fixing a mistuned Ferarri, Alfred takes a mallet and gives a whack... the engine roars to life... and a bill for $1,000. When asked why so much, he said... $1 for the fix, $999 for knowing where to whack it.
Those washers (or shims rather) are probably there to tune the center pin extension out of the 3.5mm connector to get the correct depth. Whoever took the adapter out probably accidentally unscrew the connector assembly and wasn’t careful when putting it back resulting in crushed shims wracking all sorts of havoc inside the connector.
john legros I doubt it was from the manufacture as the locations of those shims(washers) are wrong, they should all be on the front. Also, some of them are literally split and crumbled into pieces when the adapter were tightened incorrectly.
I have to pat myself on the back, at 4.26 I called RF connector. Symptoms like amplitude being dependant on frequency and absence of any output stage error were the main giveaways.
Very surprised you didn't jump on the output connector from the very start. Most obvious place for damage is always place where humans get to "interface". :) And the fact that all the self-test routines worked and showed no errors seemed to imply it was the very last stage of output that was the most likely fault location - at least that's what I guessed, based on other kit you've repaired recently with similar connector and/or cable issues. Oh well, got there in the end - and it made for a longer more interesting video. Still, I think the cat had it figured out all along. :)
Shahriar , wonder all those distortions that comes out from generator , do they make side band even from antenna ? what if those distortion goes to neighboring channel if we hade one?!
25 years ago I had a test with an Agilent phase meter. It was a Japanese instrument with the Agilent name on it. The manual was written in Engrish. I wrote a document that was how to really operate the instrument. Years later I hear there is an engineer maintaining that document.
You have illustrated this sort of fault before where the output is very low and frequency depenent. My initial thoughts were an open output. When I saw the disconnected cable I wondered if that was a way of creating a fault in case the instrument was sold off cheaply to the sabateur. In this case it seems not. I've seen tricks like this in the past with all sorts of items in for repair including cut wires hidden behind components. Shahriar, do you get to keep the instrument or return it to your supplier?
You should gage all of your 2.4 mm connectors. I fear the pin is now protruding and anything plugged into it risks being damaged. We should also find and punish the one who dared to use a wrench on that connector.
Wow!! About $100,000 used on eBay!! :-) Dear Shahriar hope you may have a bit of time to answer. I know you get countless comments even some stupid ones, just like the guy who gave your video a thumbs down because it was about an HF instrument. Both you and I were surprised and you asked him what he did expect when the title said HF? :-) Now my question, you did make a fantastic educational video about Darlington pair and frequency/delay. Do you have other similar beginner guides hidden in some of your other videos or could it maybe be possible to ask you to talk about components function in LF (DC-100MHz) vs HF (500MHz-2GHz-10GHz)?
@@octavmandru9219 Even in DC world as long as the short circuit resistance is less than source resistance, the amount of power dissipated in the short circuit is less than in the source.
Cool video. It's amazing how much STUFF is inside these instruments. Boards, interconnects, rigid piping all over.
Had a similar problem on my old Marconi 2019 with on output. Pulled it apart to check output from RF amp all good. Checked at output of attenuator all good. Turned out the sacrificial adapter and DC block had a fractured joint! As soon as I saw your fault I wondered about the output connector. Great job!
Simon Spiers , Aha! GOTCHA! LOL Ya gotta love it!
Nice repair, right in the caboose!
Hello Shahriar, I think of you as my brilliant nephew, from a long lost brother. I have been enjoying your skills, oration, and repairs for many years now, and thank you again for the service you gift us in the RUclips audience. You have the ability to give of tips and skills to repair as well one docent all in one.
Shahriar, bless you over and over again. Take care of that cool kitty, and that poor girlfriend of your's with the dirty tooth brushes....lol
Support Right to Repair movement and bill if you want to maintain the industry ability to repair devices independently.
I’ve repaired these attenuators in the past. There are little quartz/alumina attenuation tiles for each stage and I had one with a hairline crack.
Our friends at Keysight provided a new tile and with careful disassembly & re-assembly it was possible to replace it.
Alex Scarbro , Good luck with THAT! LOL
Did a similar repair to my 8566 Spec An back when it (and I) were young. HP actually sold those attenuator 'tiles' and I was able to replace the tile and got it all working. Heckuva delicate job, but saved me some bucks as the attenuator assembly was big bucks.
@@jgramsey , To me, that would be like diving into watchmaking... with a delicate escapement!
@@BruceNitroxpro And yet there are watchmakers!
Wow, two broken washers shorting out. For once, I understood the repair without too much difficulty!
I love the channel and the cat!
Absolutely love your work and knowledge, even though I’m not in this field. The troubleshooting and repair videos are awesome!
Excellent! Your well structured approach ist unmatched. But please show more of the cat. Greetings from Austria.
Yes if you bought a fixer up from eBay this would great .
But for a repair video , not as good , but makes point " sacrificial connectors " ;)
Thanks again
I tend to suspect that over-tightened sacrificial connectors are the usual mechanism by which this happens though (see Joel Dunsmore's comment). Of course, that's not a reason to avoid sacrificial connectors, just a reason to be extra extra careful when removing the sacrificial connector, because that's the moment of maximum risk.
@@jjoonathan7178 I'm not against sac. fittings , I'm for them .
I would rather ware out those , than factory panel connectors .
My cat will chew cables. He can't come in my work area. I liked the repair. It seemed really real-world, that is likely to occur for most people. Great work!
Another REPAIR video, awesome! Upvote first, watch second :) This is going to be an expensive Patreon month but I absolutely think it is worth every $.
Thanks for supporting the channel. I did not charge this video to Patreon, I only posted it there. I only charge some of the my videos to Patreon supporters.
@@Thesignalpath Yes, I know.. very considerate of you. I still think every one would for sure be worthy :) Keep up the awesome work, especially enjoying the repair videos.
Wow you got lucky! Thanks for the great video, and thanks also for showing the modulation example after the repair. 😀
That reminds me of the joke about a consultant that goes to a nuclear powerplant for troubleshooting - gets inside the machinery, takes a hammer and hit a nail - everything works fine after - bill 500k USD...after being questioned on why the bill was so high - he goes in the details and present - Hammer the nail - 1 dollar, knowing that the nail was the problem - 499,999 USD...Now I know the guy was Shahriar!
mauro sobreira , A retold story of Momo Motors in NYC... fixing a mistuned Ferarri, Alfred takes a mallet and gives a whack... the engine roars to life... and a bill for $1,000. When asked why so much, he said... $1 for the fix, $999 for knowing where to whack it.
Those washers (or shims rather) are probably there to tune the center pin extension out of the 3.5mm connector to get the correct depth. Whoever took the adapter out probably accidentally unscrew the connector assembly and wasn’t careful when putting it back resulting in crushed shims wracking all sorts of havoc inside the connector.
could be from manufactur , and with vibrations from moving the washers made a short
john legros I doubt it was from the manufacture as the locations of those shims(washers) are wrong, they should all be on the front. Also, some of them are literally split and crumbled into pieces when the adapter were tightened incorrectly.
Clumsy attempt at self-repair basically?
Its interesting, the E5071C with 20GHz is the unit out of the series that has the highest dynamic range!
I have to pat myself on the back, at 4.26 I called RF connector. Symptoms like amplitude being dependant on frequency and absence of any output stage error were the main giveaways.
Very surprised you didn't jump on the output connector from the very start. Most obvious place for damage is always place where humans get to "interface". :) And the fact that all the self-test routines worked and showed no errors seemed to imply it was the very last stage of output that was the most likely fault location - at least that's what I guessed, based on other kit you've repaired recently with similar connector and/or cable issues.
Oh well, got there in the end - and it made for a longer more interesting video. Still, I think the cat had it figured out all along. :)
I love these videos......time to go dig around eBay again.....
Illustration of one Murphy's Law corollary: It works better when you plug it in.
At 1GHz we see a harmonic at 2 GHz. At higher frequency there are no harmonics anymore. Why?
wow ! 1 crinkle washer....cheers.
Nice repair, i have here a 3 GHz version with a boot problem to see what is wrong with it.
18:55 CAT!
Holy crap; did Alltest give you that machine? That is a $100,000 dollar instrument! I even remember Alltest giving you a Keysight 3458a too!
No, it’s a loaner. :)
Your repairs are always so easy! Lucky bastard😂
$100k gear messed up by a $0.02 part.
Shahriar , wonder all those distortions that comes out from generator , do they make side band even from antenna ? what if those distortion goes to neighboring channel if we hade one?!
25 years ago I had a test with an Agilent phase meter. It was a Japanese instrument with the Agilent name on it. The manual was written in Engrish. I wrote a document that was how to really operate the instrument. Years later I hear there is an engineer maintaining that document.
How about a teardown of your 81110A that we can see in the background at the end?
You have illustrated this sort of fault before where the output is very low and frequency depenent. My initial thoughts were an open output. When I saw the disconnected cable I wondered if that was a way of creating a fault in case the instrument was sold off cheaply to the sabateur. In this case it seems not. I've seen tricks like this in the past with all sorts of items in for repair including cut wires hidden behind components.
Shahriar, do you get to keep the instrument or return it to your supplier?
The repaired instruments to back to AllTest. They will check them fully, calibrate them, etc. before they are sold.
Alltest doesnt have any technicians. It was a real silly problem any one could find.
No repair attempt is made on these instruments. They are from the warehouse.
@@Thesignalpath Someone unscrewed the cable to the attenuator.
@@electronicatutorial Yes, but not AllTest. This is how the unit was purchased from another company probably as part of a larger set of units.
innocent me, looking for this model @ eBay and BOOM! 30-80k € haha ok then, I'll stay with my 8663A :D
Did exactly the same. Poor us. Lucky we have this channel to see inside of this RF lamborgini.
@@Superhoou that's for sure! haha
You should gage all of your 2.4 mm connectors. I fear the pin is now protruding and anything plugged into it risks being damaged. We should also find and punish the one who dared to use a wrench on that connector.
The missing spacer is on the instrument side (facing towards the inside, not the user. This should help a little. :)
Wow!! About $100,000 used on eBay!! :-)
Dear Shahriar hope you may have a bit of time to answer.
I know you get countless comments even some stupid ones, just like the guy who gave your video a thumbs down because it was about an HF instrument. Both you and I were surprised and you asked him what he did expect when the title said HF? :-)
Now my question, you did make a fantastic educational video about Darlington pair and frequency/delay.
Do you have other similar beginner guides hidden in some of your other videos or could it maybe be possible to ask you to talk about components function in LF (DC-100MHz) vs HF (500MHz-2GHz-10GHz)?
Thanks, I’ll try to make more tutorials. :)
@@Thesignalpath Thank you so much, I do really appreciate that!! :-)
Think how much energy was being dissipated by that washer
Almost no energy was dissipated there. With the short most of RF energy gets reflected back to the source.
@@adamturowski3765 Unless the local impedance was close to 50 ohm, which is unlikely...
You are right! I lost touch with RF world
@@octavmandru9219 Even in DC world as long as the short circuit resistance is less than source resistance, the amount of power dissipated in the short circuit is less than in the source.
It's a piece of junk. it does not have Bluetooth. ha ha ha