No it isn't you are incorrect, the resistivity is the same for both, this is an old myth.
The use of stripline has nothing whatsoever to do with trace resistance. The advantage is when a stripline is done properly between two return paths, and it is down to the wave propagation, quasi TEM.
Look at many PC's and see how many high speed traces run on the outer layers, that work quite well......
Of course, as long as you make digital copies, they are
1- clones of the original.
2- Not dependent of a clock: just datas. (You can even recopy them with hands if you are courageous enough ;-)
There is only two times where Jitter (as well as bits accuracy) can matter, ADC & DAC.
This said, i had made some measurements on my DCX2496 when i had modified-it. Changing Power supply for low noise everywhere was a huge improvement. Changing the clock, not at all. That, i suppose, because the RFI and other pollutions added to this new clock was worse than the jitter of the original clock.
SO, using digital transport, plus a good DAC in our system, with good clock and low noise rails, and we can forget even the word "Jitter" whatever the source.
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It is quit common with people whose knowledge is entirely theory based. I know people who have designed complex circuitry who later could not trouble-shoot their own design! They only know how it is supposed to work correctly. Should a part fail, there can be all sorts of wrong voltages, currents and logic behavour and without a practical side to get experience with, they turn it over to someone else to fix. Amazing to watch. Unbelievable the first couple times i saw this happen.
BTW --
A good art on transformer caused jitter : View attachment AES2001 XFMR Jitter.pdf
THx-RNMarsh
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Flying Blind....
In my servicing experience, I usually only referred to manuals for part numbers, and that's if I had the manuals available.
When running a fix anything/everything repair shop, one has to be able to understand any new and unfamiliar item/circuit/system quickly and 99.9% of the time without schematics/manuals.
Sadly, this level of skill is fast becoming obsolete.
Jocko had a fair bit to say about SPDIF coupling transformers.
He and Phred were genuinely funny, and had great knowledge to share.
Pity they are no longer around here to break a few heads.
Dan.
Yeah, it does sound amazing.
In my servicing experience, I usually only referred to manuals for part numbers, and that's if I had the manuals available.
When running a fix anything/everything repair shop, one has to be able to understand any new and unfamiliar item/circuit/system quickly and 99.9% of the time without schematics/manuals.
Sadly, this level of skill is fast becoming obsolete.
Thanks, I will read and digest it later.
Jocko had a fair bit to say about SPDIF coupling transformers.
He and Phred were genuinely funny, and had great knowledge to share.
Pity they are no longer around here to break a few heads.
Dan.
In my case, it helps that my first job (age 13) was repairing TVs, radios, and hifi equipment. That was in the tube days, of course. This experience came in quite handy in my later career- to this day, when something breaks in the lab, I'm the one fixing it, despite being (supposedly) the manager.
The increasing dearth of real serviceable electronics has been a boon to consumers, but has robbed a generation of youngsters the chance to learn how to really get in and do board-level work. Pease's book on analog troubleshooting should be required reading for anyone putting their hands into a piece of electronics.
Just checking here. Are you pointing out something that exists with theoretical types or aiming this at a particular individual?
Personally if I had something to fix and the designer was available I'd certainly ask the questions. No point cutting off your nose to spite your face, especially if you are doing someone a favour!
What do you mean by fully metalized ones...There are very few designs that have fully metalized vias, the main choice is to fill the vias with an epoxy based filler and plate the top if required for via in pad. Most boards are standard PTH construction. The main problem with trying to get fully metalized is getting the plating down the hole, the solution has to flow down the hole....
here is an interesting note from Cree regarding thermal vias for LED applications....
Of course standard PCBs are used for many applications where these things are not a problem (automotive mil/aerospace medical) with automotive having one of the harshest environments for a PCB....., so for domestic use audio equipment there should be even less of a problem.
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SY, the schematics that you have should be adequate to allow you to repair the Vendetta easier, but it is not the EXACT schematic of the unit you have. You have a B, and the schematic is of an A. The differences are in the extra wiring that you found on the bottom of the board. However, there are other mods, C,D, and even T. Only a picture of the top side of the board will tell me what you have.
It is not necessary to understand every aspect of the Vendetta board, beyond what has already been discussed here in general, and unfortunately, IF you have lost any Toshiba jfet, you will have to return the board itself to me to repair. I have the selected Toshiba fets on hand to do this. I will charge for this, if it becomes necessary.
It is not necessary to understand every aspect of the Vendetta board, beyond what has already been discussed here in general, and unfortunately, IF you have lost any Toshiba jfet, you will have to return the board itself to me to repair. I have the selected Toshiba fets on hand to do this. I will charge for this, if it becomes necessary.
Funny you should say that. My last fortune cookie read: 'That wasn't chicken'...
If memory serves, Sansui used 122 um boards in one of their top of the line models.
After plating, you say, What if the board is not plated, but the copper wire is covered by non corrsive lacquer?
I once designed a power amp that I could not fix, so I brought in a much more experienced technician to fix it! He found that my tech had forgotten to put mica spacers under the driver devices, so they were shorted to the heatsink! What an oversight! I would hire him again in a snap. '-)
Marce, in the last 15 years or so, I haven't made a single board without full metalization of each and every through hole. It's more expensive to do initially, but it removes practically all dangers of odd connections, thus a small price to pay for my peace of mind. Full metalization under local conditions adds about 5% or so to the regular price.
A friend once had a similar problem. His amp started to behave wildy for no appearent reason. After much hassle, the problem was located at the L profile link, transferring heat of the power stage to the heat sink. While drilling the holes for the TO-3 devices, the tech failed to clean up the holes from drilled aluminium residue, so it pierced the mica and short circuited the power trannies.
The bum thing was that it happened during the amp's testing in France and to get to the bottom of it, my friend hopped on a plane to Paris, lost a day locating the problem, and flew back. All for a pretty penny.
So John, as you see, even at times of misery, you are not alone.
What do you mean full metallization.... fully coper filled holes are rarely done and would cost lots, generally to fill a via use a conductive or non conductive based epoxy, then copper plated over the top if its via in pad for SMD, if you are going to put a pin down a whole then you need a hole there....
I have not had many done in the past years, because reliability has not been a problem for the designs I have done, and testing will weed out any infant failures of an assembly, again very few.
I am doing 6oz (210um) boards at the moment... If you have plated through holes then the outer layers are going to have approx. the same thickness plating applied.
Technical Tips for PCBs - Copper Thickness, Controlled Impedance, and more! | PCB Universe
Most boards have solder mask applied during the manufacturing process.
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