Thats a great price for thew BG's definately try them. Use the Panasonic FC's in power suply areas and the BG's for signal decoupling. I still think you should try the wimma MKS2-XL, they are so cheap.
My Latvian girlfreind speaks Russian well. I asked her what I can say to you in Russian:
privet! 😀
Mike.🙂
privet! 😀
Mike.🙂
Found some WIMA MKS02 6.8uF/50V... I think they will be almost the same as 10uf mks-2xl ?
So... for about 4-5$\8pcs. and free shipping it's good deal 🙂
P.S. Spasibo tebe i tvoey podruge za pomosh 😉
So... for about 4-5$\8pcs. and free shipping it's good deal 🙂
P.S. Spasibo tebe i tvoey podruge za pomosh 😉
In the above posts where I mention the wima, please substitute the word 'polycabonate' for 'polyester. '
😀
😀
Hi SimontY,
Measure the DC offset before and after you short them out. If your DC offset exceeds 50 mV - you need that capacitor, put it back in circuit. The quest for audio nirvana should never reduce the reliability or safety of any equipment.
I'm trying to stay out of this, keep the mods in the realm of what reasonable people might try. Always keep reliability in mind while you are at it.
-Chris
Just curious. How did you come up with the "less than a volt" figure? Anything over 1/2 a volt isn't that harmful, but that is stunningly poor performance and should be corrected. Normally an acceptable limit should be 50 mV or less. The 50 mV figure has been a very common limit for amplifiers lacking a DC offset correction control.
If you have enough DC offset to heat up the voice coils, it's more than a volt. 12 VDC is enough to burn many voice coils to failure. Normal music heats up the voice coils more than a volt of DC offset ever will, thus throwing out all your T/S parameters. At higher power levels you can also lose on the other of 2 dB of efficiency.
I love that comment! DC offset exists due to design (or lack there of), luck has little to do with it.
Measure the DC offset before and after you short them out. If your DC offset exceeds 50 mV - you need that capacitor, put it back in circuit. The quest for audio nirvana should never reduce the reliability or safety of any equipment.
I'm trying to stay out of this, keep the mods in the realm of what reasonable people might try. Always keep reliability in mind while you are at it.
-Chris
Hi Mike,
Must be the beans.
When I visited in 2004, beans were supplied in great quantities with almost every meal. I understand that beans are not only the national food, but is what actually keeps the climate warm. This has zero to do with the Gulf Stream.
-Chris
Must be the beans.
When I visited in 2004, beans were supplied in great quantities with almost every meal. I understand that beans are not only the national food, but is what actually keeps the climate warm. This has zero to do with the Gulf Stream.
-Chris
Thanks!
Do you mean 'dont' forget about the buzzing? LOL! 😀
I had to buy a new meter, waiting for delivery. Then I'll check the resistors. If its not a bad resistor then I'll have to change the input selector ic. If that dont fix Im stuck!
Did your caps and Diodes arrive yet?
Do you mean 'dont' forget about the buzzing? LOL! 😀
I had to buy a new meter, waiting for delivery. Then I'll check the resistors. If its not a bad resistor then I'll have to change the input selector ic. If that dont fix Im stuck!
Did your caps and Diodes arrive yet?
Im really itching to get the new parts in but I cant until I have this buzzing sorted. As I mentioned earlier I need to check all the resistors. Boring and annoying. After that if its still buzzing I'll take a chance with the input selector, if that dosent do it I'll replace the LM3886 on the offending channel.
Im finding it hard to be enthusiastic about fixing this problem as Ive done so much allready and failed. I was even watching a 340a on ebay considering a problem free amp to start from scratch with. Saying that I'd be better off getting some audiosector PCB's and re-doing the whole thing in the existing chassis. Id look into using the channel LED outputs from the micro to control a set of relays for input switching. Ive allready got a load of nice parts to use. Also Id be able to use whatever layout I fancy to get the best results.
While Im thinking about this can anyone recomend a good preamp PCB? Something op-amp based would be prefferred for simplicity.
Mike.
Im finding it hard to be enthusiastic about fixing this problem as Ive done so much allready and failed. I was even watching a 340a on ebay considering a problem free amp to start from scratch with. Saying that I'd be better off getting some audiosector PCB's and re-doing the whole thing in the existing chassis. Id look into using the channel LED outputs from the micro to control a set of relays for input switching. Ive allready got a load of nice parts to use. Also Id be able to use whatever layout I fancy to get the best results.
While Im thinking about this can anyone recomend a good preamp PCB? Something op-amp based would be prefferred for simplicity.
Mike.
Hi Mike,
A new PCB will not have the controls in the proper location for you to begin with. However, you could certainly do things that way.
There are times when a simple problem like yours is simply due to cracked solder connections or a cracked capacitor. However, without a decent oscilloscope and meter, you're just poking around in the dark.
BTW, what meter did you end up buying? You might want to buy some 1% (or better) resistors so you can "transfer the accuracy" from those resistors to you resistance scale. This will also give you an idea how bad your ranging resistors in the meter are.
-Chris
A new PCB will not have the controls in the proper location for you to begin with. However, you could certainly do things that way.
That's called learning. No one said this would be easy, and you are trying to do things without the basic instruments. You are starting in a rut Mike.
There are times when a simple problem like yours is simply due to cracked solder connections or a cracked capacitor. However, without a decent oscilloscope and meter, you're just poking around in the dark.
BTW, what meter did you end up buying? You might want to buy some 1% (or better) resistors so you can "transfer the accuracy" from those resistors to you resistance scale. This will also give you an idea how bad your ranging resistors in the meter are.
-Chris
Hi Chris.
I ended up buying a small cheap meter on eBay - fail, I know. With Christmas on the way I decided not to spend too much. Later I'll get a Fluke.
Its so frustrating to know that this little buzz is probably something so small. I bet when I find it I'll laugh out loud! As I mentioned earlier I have a scope (borrowed) but I have no idea if it even works. Its pretty old and looks like its seen better days. Besides I have no idea how to use it! 😀
Mike.
I NEED HELP!
I ended up buying a small cheap meter on eBay - fail, I know. With Christmas on the way I decided not to spend too much. Later I'll get a Fluke.
Its so frustrating to know that this little buzz is probably something so small. I bet when I find it I'll laugh out loud! As I mentioned earlier I have a scope (borrowed) but I have no idea if it even works. Its pretty old and looks like its seen better days. Besides I have no idea how to use it! 😀
Mike.
I NEED HELP!
Pre amp kits or PCBs are not easy to find.... well I haven't found many.
I've used the B1 buffer and also a OPA2134 (also LM4562) with a LM4780 and had very good results. These were built on vero boards very easily.
You can get P88 PCBs from Rod Elliott and have used a section of the PCB in the past but was easier to do a vero board as was more suited to the schematic I used.
Altronics in Oz do a complete kit with relays etc but not cheap and the pot is bleh.
http://www.altronics.com.au/index.asp?area=item&id=K5502
http://www.altronics.com.au/index.asp?area=item&id=K5129
Twisted Pear used to have some but I think now discontinued.... maybe they might have a PCB laying around.
There are quite a few schematics in the Chip Amp forum but the same old story is which is good and which is... you know.
Plenty of power amps around but pre amps have usually been light on so usually it's a DIY type DIY pre.
I've used the B1 buffer and also a OPA2134 (also LM4562) with a LM4780 and had very good results. These were built on vero boards very easily.
You can get P88 PCBs from Rod Elliott and have used a section of the PCB in the past but was easier to do a vero board as was more suited to the schematic I used.
Altronics in Oz do a complete kit with relays etc but not cheap and the pot is bleh.
http://www.altronics.com.au/index.asp?area=item&id=K5502
http://www.altronics.com.au/index.asp?area=item&id=K5129
Twisted Pear used to have some but I think now discontinued.... maybe they might have a PCB laying around.
There are quite a few schematics in the Chip Amp forum but the same old story is which is good and which is... you know.
Plenty of power amps around but pre amps have usually been light on so usually it's a DIY type DIY pre.
Hi Mike,
-Chris
It's a start. Try to check it against a known voltage somehow.
Cool. That will last you many years. Don't throw out the cheap meter from Ebay. You can use the Fluke to calibrate the "cheapie". You can never have to many meters.
Lead dress is often the culprit. Either that or your amp may be oscillating (time to use the 'scope).
You really need to learn how to use these. A 'scope is teh thing you need most, right after a good meter. So play with the scope over the holidays. Take the amp into the loo with you, just examine it for things you may miss, No need to look hard. Just look it over many times. Something may come to you.
Don't we all. Sometimes you need to go it alone. You have the amp, not anyone else, so you are the only one who can examine it.
-Chris
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