You're right. I am sure it is an issue with my Dynasty and not the power supply. The way the BBX lights follow the power supply LED blinks seems to say that a capacitor is discharging way to soon or has just failed. I just don't want to have this $40 power supply sitting around for a paper weight now..... I took pictures of most areas before I closed the box up, what area should I look at for damage? On the main board or down by the power suppy?
Need someone to fix my Dynasty HT-959 BBX soon.Video inside!
- Thread starter blu_fuz
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Typically, the Power Supply filter capacitor is the largest capacitor in the system. Whether it's located on the Power Supply board or main board differs by design and I don't know your model well enough. Just look for the largest capacitor and it's probably the one (or two). However, as cheaply made as that Dynasty is, I'm going to guess that the manufacturers skimped wherever possible and there is probably just one. Come to think of it, didn't you already replace that one?
Blu Fuz, if you ever give on trying to fix it and wanna part it out, please hit me up. I could use a few things from it.
Keep me in mind.
Keep me in mind.
Superduper said:
I did replace one big one on the main board. Matter of fact, it is the biggest on the main board. There is another big capacitor in the power supply area that I am not sure of its condition, so it could be that one. I have enough skill to unsolder the two pins on the capacitor, find a replacement, and install it with current going in the correct direction. So first would be to find out what (if any) capacitors suck
To petey awol: NO WAY! I would never ever part this dynasty. It works well enough to keep it as is. This BBX does work and just needs electrical troubleshooting done to get it to blast the windows out of my house. Its a low volume listener right now, not a scrapper :'-( .
It was worth a shot. Can't blame a brother for trying.
On a side note, I really need to get my act together and just make a list of what I need for all my boxes that are missing dials and knobs etc...
BTW- You ever take a picture of that Dynasty extra battery door yet?
On a side note, I really need to get my act together and just make a list of what I need for all my boxes that are missing dials and knobs etc...
BTW- You ever take a picture of that Dynasty extra battery door yet?
Hey Blu. If there is a large capacitor on the power supply board, then unquestionably, that would be the first one to swap out. It may have been damaged when you had polarity hooked up incorrectly. Sometimes, they explode. Sometimes, they don't but that doesn't mean it might not have been damaged. It's cheaper to just replace than to try to determine which is good or bad. LCR meters are not cheap. Plan on spending $300 for a decent used one. That's why it's cheaper to toss in a $3 cap than to buy an LCR meter to check your caps. Also if there are any large ones around the amp area, they could also be suspect. The small ones typically won't cause the problems you are seeing. It's not that they don't fail. It's just that they are decoupling capacitors and when they fail, will cause other issues. The ones you are looking for are those that bridge the postive and negative rails.
Might I also ask you to check your speaker impedance with an ohmmeter? If they are shorted, or partially shorted, then the extra load on the amp could become a problem. Most amps are NOT stable below about 2.5 ohms or so.
Might I also ask you to check your speaker impedance with an ohmmeter? If they are shorted, or partially shorted, then the extra load on the amp could become a problem. Most amps are NOT stable below about 2.5 ohms or so.
You can check the voltage across the caps when it's powered up but you can't really check the components Value, ESR or Leakage when it's in circuit since it can't really be isolated from the circuit when it's on the board. Aside from testing for voltage across the pins, the rest really should only be tested out of circuit since LCR testers typically apply voltage to the capacitor during the test which could potentially damage other components. When it's out of circuit, there are some tests you can perform with a ohmmeter but they are just general and not exacting tests. Again, I am only talking about the large filter capacitors. The other capacitors serve different functions and you are not likely to get any intuitive readings when checking voltage across the small decoupling capacitors.
Absolutely. First you need the LCR meter to do a proper testing of a capacitor, which is very costly. Then you need to remove the cap from the circuit. If you don't remove the whole thing, you can disconnect one leg. I think it's always easier to just replace, especially when a particular component is suspect.
Good tips again super duper - I had a horrible time finding a company with the other parts I had replaced already. I will inspect and remove big capacitors by the power supply board. I know I have pictures of that area, just not loaded into photobucket yet.......
Again, here is the one I repaced before. It is bright blue, and shown below is the black one I took out. Yes, it was installed the correct direction
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Again, here is the one I repaced before. It is bright blue, and shown below is the black one I took out. Yes, it was installed the correct direction
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i have no exact ideia,blu_fuz said:I found the pic I took before of the capacitor on the power supply board. Not sure what it is though:
but id say by the amount of diodes,
its a rectifier.
to clean current from AC ( from HUM ).
but hey IM
that was a tasty capacitor THOUGH. yum
That cap looks like it could be anywhere from 2200uf, 3300uf or even 4400uf. It all depends upon the voltage rating. Higher voltage ratings results in larger sized caps.
But those diodes are HUGE. They are about the size of the diodes in my RX-7700. Looks like your box clearly has very high power requirements. Normally, there are 4 diodes in the PS forming what is known as a bridge rectifier. I see 6 here, so don't know what the functions of the other 2 are. Those diodes should be checked as well.
But those diodes are HUGE. They are about the size of the diodes in my RX-7700. Looks like your box clearly has very high power requirements. Normally, there are 4 diodes in the PS forming what is known as a bridge rectifier. I see 6 here, so don't know what the functions of the other 2 are. Those diodes should be checked as well.
The blue cap you replaced is a 3300uf25v.
But I swear the original black "Grand" brand cap says 3800uf25v on one end.
Could this be part of the problem?
(I have no electrical knowledge like Norm. This is just a question.)
But I swear the original black "Grand" brand cap says 3800uf25v on one end.
Could this be part of the problem?
(I have no electrical knowledge like Norm. This is just a question.)
No. 3800uf would be a very unusual value and you would have to search the globe several times over to find one. Typically, those caps are sleeved with heat shrink tubing that is preprinted all along it's length. You can clearly see 3300uf and the 3800uf that you see is probably glue residue bridging the text. Standard caps go in decades of the following values: 1, 2.2, 3.3, 4.7, 6.8 -- then 10, 22, 33, etc. Using 1 increment up or down probably wouldn't have any real noticeable effect unless it was a very sensitive timing circuit.
In any event, as to your question, it wouldn't contribute to the problem. These capacitors, used in this capacity aren't very sensitive to value changes. In fact, the accuracy of these components are like 20% tolerance anyhow so a 3300uf coud actually read 20% off and STILL be normal. Audio system hot-rodders frequently over cap their system with higher valued capacitors in an attempt to extract more performance from their system. As long as the Power Supply has sufficient capacity, upgrading that cap (say from 3300uf) to 4700uf, or even more, would probably have a positive effect on performance. Overdoing it would throw things off however, and may even strain other components.
In any event, as to your question, it wouldn't contribute to the problem. These capacitors, used in this capacity aren't very sensitive to value changes. In fact, the accuracy of these components are like 20% tolerance anyhow so a 3300uf coud actually read 20% off and STILL be normal. Audio system hot-rodders frequently over cap their system with higher valued capacitors in an attempt to extract more performance from their system. As long as the Power Supply has sufficient capacity, upgrading that cap (say from 3300uf) to 4700uf, or even more, would probably have a positive effect on performance. Overdoing it would throw things off however, and may even strain other components.
Ok, looks like I will have to go in the box again and find out the value of the capacitor and the diodes. Do you have a electronics link for types of diodes like the ones shown? I have an extra 3300 capacitor so I am hoping that is the value so I don't have to go searching for one of those too.
Is there any specific info that I need to find on the diodes?
Is there any specific info that I need to find on the diodes?
I talked to our audio specialist guy who did the soldering for me before, he thinks that the power supply isn't sufficent enough. He is thinking that because the batteries and the power supply work off the same board essentially and if the batteries work even a little, that it is most likely the power supply. Does anyone concur? I would like to sell or return it but don't want it gone if I can truely use it.
......
- I still have it. Just checking in again 
Hahaha, you had me for a second there,..... Don't ever do that again!!!
Like Journey say Blu, don't stop believin'
Rock On.
Like Journey say Blu, don't stop believin'
Rock On.
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