Okay, I finally ordered 6 35 volt 2200uf caps for my Behringer DSP9024.
I will be replacing the 16 volt 2200uf with a 35 volt one then I will test the unit to see if I need to also replace those two 35 volt 2200uf caps. If it powers up with just replacing that one 16 volt capacitor, I might just go with that and save the other 5 for a future malfunction.
Here is the capacitor I bought 6 of and which supplier I went with.
https://www.parts-express.com/2200uf-35v-radial-mini-electrolytic-capacitor--020-1176
I will update this thread with the results, once my order comes in and I solder those 3 caps pictured in my first post back into the main board (minus the leaking one) and power the unit up for a test run.
Okay folks, I realize this post will not be viewed or willl be buried in other posts, but here is the results of my capacitor replacement in my Behringer DSP9024 processor.
I decided to replace all 3 capacitors on the DSP9024 main board in the power supply section with 2200uf 35 volt capacitors, the original C85 capacitor which was 16 volts, was replaced with one of the new 35 volt capacitors.
Now the results, the unit powered up successfully with no issues, although the user programmed settings are gone, the factory pre-sets are still in memory.
I am not worried about my user pre-sets, because I had those saved on my computer as a text file. It is just a matter of re-programming the empty slots again.
So, if your Behringer DSP9024 starts cycling the start up screens repeatedly and the button LEDS are all blinking, it means C85 most likely failed, replace with a higher voltage capacitor and you're once again good to go.
By the way, make sure you apply artic silver 5 heat sink compound on those voltage regulators where they mate with the heat sink, but be sure to clean off the surfaces before hand. Don't forget place that insulator under that regulator closest to C85 or you risk a short. I have my unit closed up now, so I can't tell you which one it is. and make sure that ceramic insulator is on that screw that holds the regulator down on the heat sink or that can also cause a short to ground.
Good luck and get those dead DSP9024 units up and running again, I have proof that replacement of capacitor C85 brings these units back to life. So put the word out there so other people know how to bring their hardware back to life again and out of the junk piles.
If you have read this, please let me know by responding below.
Bruce.
Great! Mr. Bruce.
There have been many filter capacitor problems with equipment over the past 10-15 years! It was an epidemic with computer motherboards and video cards, and blamed on defective caps. The symptom would be when you'd try to do some heavy work, with either the processor or video, the computer would wink off and reboot or just freeze. The caps would then have popped tops and low capacitance. So much equipment went down the drain because of this problem. I don't know when your processor was made, but it might have used some of the defective caps.
Even in recent times caps blow, and I don't think it's all because of capacitor defects, but that caps in power supplies are filtering much higher frequencies now, 50 to 100's of khz rather than just 120 cycles. Standard electrolytic caps have higher impedance at 100 khz and to the square waves that might reach them, so there's more heating.
If you have a switching supply, look for low impedance caps, low ESR versions from welll known companies. They might cost more than standard, but you want them for switching supplies.
You could use the same or higher voltage, like going from 16 to 25 volts, and increase the capacitance some, like going from 2200 uf to 3300 uf should be fine, but I don't like to get carried away on that.
"Capacitor Plague".
I did more reading on capacitors and their problems, and WikiPedia has a good rundown on the problem and about liquid based electrolytic caps in general, when a new formula for water based electrolytic caps was introduced to make low ESR caps:
https://en.wikipedia.org/wiki/Capacitor_plague
"
Water-based electrolyte
At the end of the 1990s a third class of electrolytes was developed by Japanese researchers.
- Water-based electrolytes, with up to 70% water, for so-called "low-impedance", "low-ESR", or "high-ripple-current" electrolytic capacitors with rated voltages up to 100 V,[18] for low-cost mass-market applications. The capacitor plague is due to faulty electrolytes of this type.
Development of a water-based electrolyte
At the beginning of the 1990s—having in mind that water, with its high permittivity of ε = 81, is a powerful solvent for electrolytes, water having the ability to hold high, conductivity-enhancing concentrations of salt ions in solution—some Japanese manufacturers started the development of a new, low-ohmic water-based class of electrolytes, with significantly improved conductivity, compared to electrolytes with organic solvents like GBL. But water will react quite aggressively and even violently with unprotected aluminum, converting metallic aluminum (Al) into aluminum hydroxide (Al(OH)3), via a highly exothermic reaction that gives off heat, causing gas expansion that can lead to an explosion of the capacitor. Therefore, the main problem in the development of water-based electrolytes is achieving long-term stability by hindering the corrosive action of water on aluminum.
Normally the anode foil is covered by the dielectric aluminum oxide (Al2O3) layer, which protects the base aluminum metal against the aggressiveness of aqueous alkali solutions. However, some impurities or weak points in the oxide layer offer the possibility for water-driven anodic corrosion that forms aluminum hydroxide (Al(OH)3). In e-caps using an alkaline electrolyte this aluminum hydroxide will not be transformed into the desired stable form of aluminum oxide. The weak point remains and the anodic corrosion is ongoing. This corrosive process can be interrupted by protective substances in the electrolyte known as inhibitors or passivators.[31][37] Inhibitors—such as chromates, phosphates, silicates, nitrates, fluorides, benzoates, soluble oils, and certain other chemicals—can reduce the anodic and cathodic corrosion reactions. However, if inhibitors are used in an insufficient amount, they tend to increase pitting.[38]
The Japanese manufacturer Rubycon was a leader in the development of new water-based electrolyte systems with enhanced conductivity in the late 1990s.[citation needed] After several years of development, researchers led by Shigeru Uzawa had found a mixture of inhibitors that suppressed the aluminum hydration. In 1998, Rubycon announced two series, ZL and ZA, of the first production capacitors using an electrolyte with a water content of about 40%, which were suitable for temperatures ranging from −40 °C (−40 °F; 233 K) to 105 °C (221 °F; 378 K). Later, electrolytes were developed to work with water of up to 70% by weight.[citation needed] Other manufacturers, such as NCC,[39] Nichicon,[40] and Elna[41] followed with their own products a short time later.
The improved conductivity of the new electrolyte can be seen by comparing two capacitors, both of which have a nominal capacitance of 1000 µF at 16 V rated voltage, in a package with a diameter of 10 mm and a height of 20 mm. The capacitors of the Rubycon YXG series are provided with an electrolyte based on an organic solvent and can attain an impedance of 46 mΩ when loaded with a ripple current of 1400 mA. ZL series capacitors with the new water-based electrolyte can attain an impedance of 23 mΩ with a ripple current of 1820 mA, an overall improvement of 30%.
The new type of capacitor was called "Low-ESR" or "Low-Impedance", "Ultra-Low-Impedance" or "High-Ripple Current" series in the data sheets. The highly competitive market in digital data technology and high-efficiency power supplies rapidly adopted these new components because of their improved performance. Furthermore, by improving the conductivity of the electrolyte, capacitors not only can withstand a higher ripple current rating, they are much cheaper to produce since water is much cheaper than other solvents. Better performance and low cost drove widespread adoption of the new capacitors for high volume products such as PCs, LCD screens, and power supplies.
Industrial espionage implicated
Industrial espionage was implicated in the capacitor plague, in connection with the theft of an electrolyte formula. A materials scientist working for Rubycon in Japan left the company, taking the secret water-based electrolyte formula for Rubycon's ZA and ZL series capacitors, and began working for a Chinese company. The scientist then developed a copy of this electrolyte. Then, some staff members who defected from the Chinese company copied an incomplete version of the formula and began to market it to many of the aluminium electrolytic manufacturers in Taiwan, undercutting the prices of the Japanese manufacturers.[1][42] This incomplete electrolyte lacked important proprietary ingredients which were essential to the long-term stability of the capacitors[4][23] and was unstable when packaged in a finished aluminum capacitor. This faulty electrolyte allowed the unimpeded formation of hydroxide and produced hydrogen gas.[34]
There are no known public court proceedings related to alleged theft of electrolyte formulas. However, one independent laboratory analysis of defective capacitors has shown that many of the premature failures appear to be associated with high water content and missing inhibitors in the electrolyte, as described below.
Evidence of insufficient composed electrolyte
Unimpeded formation of hydroxide (hydration) and associated hydrogen gas production, occurring during "capacitor plague" or "bad capacitors" incidents involving the failure of large numbers of aluminum electrolytic capacitors, has been demonstrated by two researchers at the University of Maryland who analyzed the failed capacitors.[34]
The two scientists initially determined, by ion chromatography and mass spectrometry, that there was hydrogen gas present in failed capacitors, leading to bulging of the capacitor's case or bursting of the vent. Thus it was proved that the oxidation takes place in accordance with the first step of aluminum oxide formation.
Because it has been customary in electrolytic capacitors to bind the excess hydrogen with the help of reducing or depolarizing compounds, such as aromatic nitrogen compounds or amines, to relieve the resulting pressure, the researchers then searched for compounds of this type. Although the analysis methods were very sensitive in detecting such pressure-relieving compounds, no traces of such agents were found within the failed capacitors.
In capacitors in which the internal pressure build-up was so great that the capacitor case was already bulging but the vent had not opened yet, the pH value of the electrolyte could be measured. The electrolyte of the faulty Taiwanese capacitors was alkaline, with a pH of between 7 and 8. Good comparable Japanese capacitors had an electrolyte that was acidic, with a pH of around 4. As it is known that aluminum can be dissolved by alkaline liquids, but not that which is mildly acidic, an energy dispersive X-ray spectroscopy (EDX or EDS) fingerprint analysis of the electrolyte of the faulty capacitors was made, which detected dissolved aluminum in the electrolyte.
To protect the metallic aluminum against the aggressiveness of the water, some phosphate compounds, known as inhibitors or passivators, can be used to produce long-term stable capacitors with high-aqueous electrolytes. Phosphate compounds are mentioned in patents regarding electrolytic capacitors with aqueous electrolytic systems.[43] Since phosphate ions were missing and the electrolyte was also alkaline in the investigated Taiwanese electrolytes, the capacitor evidently lacked any protection against water damage, and the formation of more-stable alumina oxides was inhibited. Therefore, only aluminum hydroxide was generated.
The results of chemical analysis were confirmed by measuring electrical capacitance and leakage current in a long-term test lasting 56 days. Due to the chemical corrosion, the oxide layer of these capacitors had been weakened, so after a short time the capacitance and the leakage current increased briefly, before dropping abruptly when gas pressure opened the vent. The report of Hillman and Helmold proved that the cause of the failed capacitors was a faulty electrolyte mixture used by the Taiwanese manufacturers, which lacked the necessary chemical ingredients to ensure the correct pH of the electrolyte over time, for long-term stability of the electrolytic capacitors. Their further conclusion, that the electrolyte with its alkaline pH value had the fatal flaw of a continual buildup of hydroxide without its being converted into the stable oxide, was verified on the surface of the anode foil both photographically and with an EDX-fingerprint analysis of the chemical components.
"
I urge reading the whole article, it's also informative on the process behind how electrolytic caps are made.
https://en.wikipedia.org/wiki/Capacitor_plague
Informative Wiki-link on electrolytics, Mr. Crime. Appreciate that.
Electrolytic and other capacitors have been the subject of the month at my desk where I'm picking out replacements for about ten electrolytics in the LPB AM2-20 Carrier Current Transmitter, which blew a series diode because of suspected bad caoacitor.
This transmitter dates back to the 90s and has changed hands a few times and had the frequency of operation changed more than twice.
The circuit section being rebuilt powers the BIAS power supply for the linear RF output stage.
Most of the electrolytics being removed are the tantalum type, which I don't believe were original LPB parts. They were used because of the small size required for the circuit locations, and I'm selecting from non-tantalum miniatures with appropriate lead-spacing.
My supplier for this will be Mouser Electronics.
At the same time I'm looking at changing the frequency of an LPB AM-5 Carrier Current Transmitter which will require different RF caps in the output filter... a real difficult card to remove from deep inside the little cabinet.
Mr. Bruce, your description of rappers being motivated by high-speed woman's vibrator makes me laugh.
First, let me get the woman's high speed vibrator out of the way. I am not sure what the station manager is thinking if it is his/her decision to reprocess the music using high compression, or if the songs are sold to the station that way. I know the station uses computers to play their music, not a CD player.
But every song has that distinct vibrato effect in the MID to BASS region, it sort of makes the music flutter so to speak, it is very noticeable on adjacent channels where you could be listening to 107.3 on a car stereo while driving and suddenly you can hear the thumping of 107.7's vibrating BASS intermoding on the carrier of the station on 107.3.
I could do a youtube video showing examples of what I am saying, but then again, the station in question could request youtube to remove the video due to copy right infringment, recording their station and presenting a public exibition without their permission or consent.
Years back I was a regular at another popular forum board, where I helped people in the computer hardware section. I often used the wikipedia writeup Nate Crime posted in this thread as an example as to what can happen to power supply capacitors and filter capacitors on a computer main board after years of continous use.
My Behringer DSP9024 has been in operation since July 7th and it has been running flawlessly ever since.
I reprogrammed program 19 with my original MrBruce created settings, I have left program 17 and 18 blank for now as those were just settings I programmed from an on line post another DSP9024 owner posted on line.
The settings I created are working flawlessly as they did before the DSP9024 started failing to boot up properly.
For FM I have the compression threshold for both channel 1 and channel 6 set at --70dB, this basically makes both channels FULLY COMPRESSED and not making to the output, the purpose is to prevent BASS overload in the 25.000Hz to 63.000Hz region and to protect the pilot carrier frequency by fully compressing the 6.3000KHz to 20.000KHz region. The rest of the 6 bands are at --35dB to --27dB having MUCH LESS compression and thus is present in the outputs with very little limiting. The end result is no pilot light blinking and no over driven BASS on songs that are highly compressed at the recording studio.
Formating on this site is tough to create a column type settings graph so you can see all my settings for all 6 channels and have them line up properly, so it is difficult for me to share settings with you all.
Bruce.