Underneath the text editor is a box called "Additional Options" and a button called "Manage attachments" Click on this and a new "attachments" window opens up.
From there you can upload pics from your computer or a web address.
No need for hosting!
And then when you want to get all fancy-pants with alt-print screen and MS Paint, you can do this:
Look at all the cool things you can attach: .pdf spec sheets, word documents, big zipped files, even weird Photoshot documents? .psd ?
From there you can upload pics from your computer or a web address.
No need for hosting!
And then when you want to get all fancy-pants with alt-print screen and MS Paint, you can do this:
Look at all the cool things you can attach: .pdf spec sheets, word documents, big zipped files, even weird Photoshot documents? .psd ?
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Yikes, I had to dig that out!
Can you tell me more?
My Cousin had one of the early 14 bit players a TDA1540 (?) if memory serves. Built like a tank. Later he purchased an early Magnavox 16 bit TDA1541 non-A player. I think he had 3 at one point, different models. In the early 90's he purchased the S1 crown dacs (2). Did lots of decoupling cap mods as well as designing glue logic to run the NPC SM5814 digital filter in the I2S environment. It worked and was an audible improvement. He eventually tried a dac board with lots of regulation unfortunately he kept the Sallen Key filter. A poor filter for audio. So his results were so so. He eventually moved onto Delta Sigma dacs. He gifted me his S1 crown so I have a pair. It was his idea actually for me to switch to a different input receiver so I could send Sony (2's complement, MSB first, right justified data) to the NPC filter (no glue logic). A simple adapter. Going back now to about 1997 I tried my hand at building an I/V + GIC Bessel filter + Buffer. That combination was a huge improvement over the stock implementation. Eventually my laser quit and I purchased the Analogmetric board and salvaged that board for the analog stage and so here I am. Crazy after all these years.
I saw in our domestic forum, few PCBs are available from today. Who want them, to try to contact the man.
Hi Dave,
I replaced the 2.2 ohm resistor. I think the board is bad. I get noise at the output whether or not a signal is on the input. If I hook up the coax cable, I get noise on the cs8414. It swamps the signal, so I don't see a difference when I start and stop play. If I disconnect the digital cable digital noise stops, but I still see analog junk at the output. I've been using a toroid transformer. Also I see noise on pins 7 thru 13 and pin 18 thru 24 which seem to indicate a possible poor ground. But I can't verify that by measurement. Maybe that's the culprit. Any ideas about other sources of noise.
I replaced the 2.2 ohm resistor. I think the board is bad. I get noise at the output whether or not a signal is on the input. If I hook up the coax cable, I get noise on the cs8414. It swamps the signal, so I don't see a difference when I start and stop play. If I disconnect the digital cable digital noise stops, but I still see analog junk at the output. I've been using a toroid transformer. Also I see noise on pins 7 thru 13 and pin 18 thru 24 which seem to indicate a possible poor ground. But I can't verify that by measurement. Maybe that's the culprit. Any ideas about other sources of noise.
Noise
Hi Dwight, Sorry for all the troubles. Hmmmm. I am troubled by the fact that the 2.2 Ohm resistor burned. That is the analog and digital ground, where they come together. If your using a single torroid, I use several. Then it is unlikely that the primary is anti-phase. So what torroid are you using the one Analogmetric sells? I bought 2 and one was bad out of the box. I am wondering if you have the center tap wrong on the analog supply. If that was so.... It might put enough juice through the ground point to offset the digital side. Wish I could see a photo. It might be something another set of eyes would catch right off then again maybe not. If the LM317, LM337 was transposed I am not sure what that would do. My eyes are giving me grief since turning 50. I use a giant magnifier with a light. And glasses for close up. It may be a situation as I described before where you divide and conquer the issue. Power up each section independently. Test test and test again. Hope some of that helps.... Dave
Hi Dwight, Sorry for all the troubles. Hmmmm. I am troubled by the fact that the 2.2 Ohm resistor burned. That is the analog and digital ground, where they come together. If your using a single torroid, I use several. Then it is unlikely that the primary is anti-phase. So what torroid are you using the one Analogmetric sells? I bought 2 and one was bad out of the box. I am wondering if you have the center tap wrong on the analog supply. If that was so.... It might put enough juice through the ground point to offset the digital side. Wish I could see a photo. It might be something another set of eyes would catch right off then again maybe not. If the LM317, LM337 was transposed I am not sure what that would do. My eyes are giving me grief since turning 50. I use a giant magnifier with a light. And glasses for close up. It may be a situation as I described before where you divide and conquer the issue. Power up each section independently. Test test and test again. Hope some of that helps.... Dave
merlin2069er
"Just ordered some red baron boards from Oliver. " Hi Merlin, That is a sore subject in these parts. I didn't get my boards either. That is why we are sensitive here. Either they are coming by pack mule via Tibet or there is something else going on here.
Hope you get yours.... Dave
"Just ordered some red baron boards from Oliver. " Hi Merlin, That is a sore subject in these parts. I didn't get my boards either. That is why we are sensitive here. Either they are coming by pack mule via Tibet or there is something else going on here.
Hope you get yours.... Dave
Transformers
Hi wlowes, I still hold out some small hope that the mule survived the trip across Tibet and somehow the boards show up. I'm not really blaming Oliver, as once it is posted it's not within his sphere of influence. Just bad luck maybe. ctef, No you can't run the digital side from 1 transformer winding. You could get a transformer with 2 secondaries. If you get one with 15 VAC winding, that would work. I think you have 220 VAC in that part of the world. Use 1 winding for the +5 supply and the other for the -15 supply. The regulators are shunt regulators so they will radiate a little extra heat. I like to use a dedicated transformer for the analog side. Hi msmart2b, Sounds like a plan on the 20-0-20 for the analog supply. It's a little high at 28 VDC raw, so your heatsinks will get warm. With just the stock opamps it should be OK. Adjust the analog power supply without the opamps in circuit. I'd go + and - 15 VDC on the regulators. Hope that helps, Dave..... Forgive my not cutting and pasting, will try that next post AudioLapDance
Hi wlowes, I still hold out some small hope that the mule survived the trip across Tibet and somehow the boards show up. I'm not really blaming Oliver, as once it is posted it's not within his sphere of influence. Just bad luck maybe.
ctef, No you can't run the digital side from 1 transformer winding. You could get a transformer with 2 secondaries. If you get one with 15 VAC winding, that would work. I think you have 220 VAC in that part of the world. Use 1 winding for the +5 supply and the other for the -15 supply. The regulators are shunt regulators so they will radiate a little extra heat. I like to use a dedicated transformer for the analog side. Hi msmart2b, Sounds like a plan on the 20-0-20 for the analog supply. It's a little high at 28 VDC raw, so your heatsinks will get warm. With just the stock opamps it should be OK. Adjust the analog power supply without the opamps in circuit. I'd go + and - 15 VDC on the regulators. Hope that helps, Dave..... Forgive my not cutting and pasting, will try that next post AudioLapDance May be is time for question about the choice of right capacitors.
For electrolytic I stopped on Panasonic FC series and Os-con SEPC. May be they don't need bypasses?
About TDA decoupling. I want to use SMD(SMT) capacitors under IC. Are any other types except Cornell Dubilier 1uF film-capacitors suitable for this? 1uF Ceramic SMD?
For electrolytic I stopped on Panasonic FC series and Os-con SEPC. May be they don't need bypasses?
About TDA decoupling. I want to use SMD(SMT) capacitors under IC. Are any other types except Cornell Dubilier 1uF film-capacitors suitable for this? 1uF Ceramic SMD?
Capacitors
Hi ctef, The Panasonic FC's are very good as are the Os-con SEPC. I have used Nichicon Gold Tune and some other gold Nichicon series. I think a good bypass is a benefit. I used Wima's. It helps with high frequency noise. TDA decoupling, yes I like PPS (Polyphenol Sulfide) SMD capacitors. I would recommend doing the copper foil and following Thorsten's instructions. There is a link back a few post thanks to AudioLapDance. Minimum value is .1 uF, I would do some measuring put in what fits. I tried the Cornell Dubilier 1 uF. Had some soldering issues with those. So switched to the PPS, I think they are Panasonic. Digikey had them and I live in the same state in the USA. Another way is shown by ECDesign's. I'll see if I can find his picture. I actually put my capacitors under the chip and not on the back, used a starch plastic socket. These dissolve leaving standing pins. Doing it on the bottom of the board as Thorsten shows is fine too. Dave
Hi ctef, The Panasonic FC's are very good as are the Os-con SEPC. I have used Nichicon Gold Tune and some other gold Nichicon series. I think a good bypass is a benefit. I used Wima's. It helps with high frequency noise. TDA decoupling, yes I like PPS (Polyphenol Sulfide) SMD capacitors. I would recommend doing the copper foil and following Thorsten's instructions. There is a link back a few post thanks to AudioLapDance. Minimum value is .1 uF, I would do some measuring put in what fits. I tried the Cornell Dubilier 1 uF. Had some soldering issues with those. So switched to the PPS, I think they are Panasonic. Digikey had them and I live in the same state in the USA. Another way is shown by ECDesign's. I'll see if I can find his picture. I actually put my capacitors under the chip and not on the back, used a starch plastic socket. These dissolve leaving standing pins. Doing it on the bottom of the board as Thorsten shows is fine too. Dave
Here is a way to do it.
http://www.diyaudio.com/forums/digi...e-nos-dac-using-tda1541a-377.html#post2679091
http://www.diyaudio.com/forums/digi...e-nos-dac-using-tda1541a-377.html#post2679091
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