Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 27, 2013 3:07:29 GMT -6
Would really appreciate some help. I am building the current (2.2) version of the MNATS 1176 REV D and had a bit of a noobish question!!!
For 3 capacitors on the PCB, the BOM says I can use either Electrolytic or Fim caps.
I only have Electrolytic which I know have polarity. The problem is the PCB has no polarity indications for these positions.
Am I right that, because in these positions I can use Film caps (which I know have no polarity), I can put the Electrolytics any way round ? Or should they still observe polarity ?
I am sure the answer is to be found in the supplied schematic but I can't trust my interpretation of it just yet!!!
with many thanks,
Pace
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 27, 2013 9:21:42 GMT -6
Just wanted to answer my own question in case it is useful to anyone.
Although not printed on the PCB, the polarity of these caps is indicated on the overlay included in the BOM
Pace
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 27, 2013 11:33:52 GMT -6
I don't want to step on any toes, but questions like this should be placed in the official support thread, over on GroupDIY where MNats posts and checks in. Also, hundreds of other people who built them can chime in and answer.
|
|
|
Post by tonycamphd on Jul 27, 2013 12:45:09 GMT -6
Just wanted to answer my own question in case it is useful to anyone. Although not printed on the PCB, the polarity of these caps is indicated on the overlay included in the BOM Pace Hi Pace, all good questions, this thread www.groupdiy.com/index.php?topic=20058 although huge, is the place to go, if you use the search within thread function, you will find everything you need to be successful with the Rev D build, that thing sounds killer good luck
|
|
|
Post by Johnkenn on Jul 27, 2013 23:18:36 GMT -6
I don't want to step on any toes, but questions like this should be placed in the official support thread, over on GroupDIY where MNats posts and checks in. Also, hundreds of other people who built them can chime in and answer. Well, it's no big deal...I appreciate Pace bringing this to my attention. I'd love to have a DIY 1176...Just gotta learn how to DIY...
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 28, 2013 5:52:29 GMT -6
John, really, if I can do it you can!!!
Jump in! It is fun.
|
|
|
Post by Gustav on Jul 28, 2013 6:05:44 GMT -6
Am I right that, because in these positions I can use Film caps (which I know have no polarity), I can put the Electrolytics any way round ? Or should they still observe polarity ? As a more general answer. Always observe the correct polarity of polarized caps. Gustav
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 28, 2013 8:02:05 GMT -6
thanks Gustav
|
|
|
Post by tonycamphd on Jul 28, 2013 11:20:31 GMT -6
Am I right that, because in these positions I can use Film caps (which I know have no polarity), I can put the Electrolytics any way round ? Or should they still observe polarity ? As a more general answer. Always observe the correct polarity of polarized caps. Gustav Gustav is 100% correct, reverse the polarity of polarized caps, and they will pop! shortly after power is applied, and probably damage other components in the circuit, if theyre biggies, they'll pop like an M80 firecracker! IMO, If a BOM gives me a choice to use electrolytics or film caps, polarity isn't an issue, said pieces are in the audio path, and they'll fit? i will always choose film caps. It's pretty common knowledge that they have a smaller footprint on the sound.
|
|
|
Post by unit7 on Feb 17, 2014 16:05:49 GMT -6
I've just started this build. Went for the complete kit (rev D) from Hairball. Just wanted to say that the care Mike has put in making these kits is just amazing. The packaging, labeling, the gorgeous metalwork, everything! Also I love the build guide, super detailed and educating. I've been a bit scared of working with high voltage, but after reading Mike's instructions on how to wire the power transformer (both U.S and EU) a few times I'm getting it. This is encouraging for my upcoming LA2 p2p build.
|
|
|
Post by Johnkenn on Feb 17, 2014 17:53:16 GMT -6
Well, unfortunately, Pace won't be here to help you through the build.
|
|
|
Post by svart on Feb 17, 2014 19:17:03 GMT -6
I've just started this build. Went for the complete kit (rev D) from Hairball. Just wanted to say that the care Mike has put in making these kits is just amazing. The packaging, labeling, the gorgeous metalwork, everything! Also I love the build guide, super detailed and educating. I've been a bit scared of working with high voltage, but after reading Mike's instructions on how to wire the power transformer (both U.S and EU) a few times I'm getting it. This is encouraging for my upcoming LA2 p2p build. No worries. AC is safer than DC to work with. With DC your muscles lock up due to the constant current. With AC, your muscles get a chance to loosen 25/30 times a second as the wave crosses zero!
|
|
|
Post by svart on Feb 18, 2014 8:57:48 GMT -6
And don't worry, the build is pretty easy. I've done a few hairballs after doing my own clone layout many many years ago. I greatly prefer the hairballs in ease of build. If you need help, let me know.
|
|
|
Post by unit7 on Feb 18, 2014 10:56:02 GMT -6
Thanks Svart! But I do feel pretty cool this time. Had a few 'gulp' moments with the 51X rack floorbox PSU last summer. Not because it was bad but because I'm a noob and felt there were a couple of blanks I couldn't fill. Mike's build manual is perfect for me. Educating stuff. BTW, I happened to stumble on one of the old classic pics of Bill Putnam the other day. Quite extraordinary that so many of the old designs still live and that we're making the IKEA version of his creation at our homes almost 50yrs later!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Feb 18, 2014 11:55:59 GMT -6
Yepp, there are incredibly great kits out these days. Sometimes i think we came to the point of "Mona Lisa with paint-by-numbers", meanwhile....
|
|
brent
New Member
Posts: 1
|
Post by brent on Feb 18, 2014 22:13:34 GMT -6
Thanks Svart! But I do feel pretty cool this time. Had a few 'gulp' moments with the 51X rack floorbox PSU last summer. Not because it was bad but because I'm a noob and felt there were a couple of blanks I couldn't fill. Mike's build manual is perfect for me. Educating stuff. BTW, I happened to stumble on one of the old classic pics of Bill Putnam the other day. Quite extraordinary that so many of the old designs still live and that we're making the IKEA version of his creation at our homes almost 50yrs later! I'm building a full Hairball 1176D right now. The one thing I did after testing the power supply, was to discharge the electrolytic caps in the power supply section with an 800 ohm, 5Watt resistor I had around. I'm not sure how dangerous they are in this build, but I got into the habit of discharging dangerous caps when I was doing my Marshall Plexi build back when. It was one thing I noticed missing from the hairball build docs, but I think it's better to be safe when dealing with power supply builds. I did search the build support thread to see if the question was ever raised, and it was. Hairball said he never discharges them before stuffing the rest of the board, but it's not a bad idea. He suggests a 200 ohm 5 Watt resistor attached to insulated clips. Cheers, -B
|
|
|
Post by svart on Feb 19, 2014 8:59:58 GMT -6
Most soldering irons are grounded in their tips, so the moment you touch the board with the soldering iron, you'll likely discharge the traces anyway. The caps on the build aren't big enough to cause too much issue. The threshold of human skin for conducting current is around 15VDC, so anything below won't have much effect unless you are wet. Besides, the cap values don't hold enough charge to conduct far enough along the skin to affect the heart.
The voltages and currents used in a tube amp are much higher and are potentially harmful/deadly. I would definitely either let the amp discharge over a few minutes or drain the caps with a resistor.
|
|
|
Post by unit7 on Feb 26, 2014 14:44:41 GMT -6
Just did the calibration on my rev D. Again, this kit is awesome! Except for the physical range of the input/output pots not matching the markings on the faceplate, which I obviously can't fix, I've had zero issues, and having all parts including cables and shrink tubes (and a nice guide on how to twist cables) I managed to make it tidy and clean internally. I don't at all understand the issues some people seem to have over at the 1176 shootout thread. It sounds just great! Compared to Purple and Don Classics rev A on drums and acoustic bass. Very close to the Purple. I believe it had a bit more lo end than the Purple and preferred it on higher input/lightly distorted settings. I'll probably have to go for a rev A eventually Attachments:
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Feb 26, 2014 14:52:11 GMT -6
Congratulations! (DIY rules.)
|
|
|
Post by svart on Feb 26, 2014 15:11:48 GMT -6
Just did the calibration on my rev D. Again, this kit is awesome! Except for the physical range of the input/output pots not matching the markings on the faceplate, which I obviously can't fix, I've had zero issues, and having all parts including cables and shrink tubes (and a nice guide on how to twist cables) I managed to make it tidy and clean internally. I don't at all understand the issues some people seem to have over at the 1176 shootout thread. It sounds just great! Compared to Purple and Don Classics rev A on drums and acoustic bass. Very close to the Purple. I believe it had a bit more lo end than the Purple and preferred it on higher input/lightly distorted settings. I'll probably have to go for a rev A eventually Awesome. It's an easy kit. I think the thing that hangs most people, besides soldering issues, is that they don't read the resistors properly. I'm pretty good at it, but I'll double check every single one with a meter. Also, with the different versions, some resistor values are different and people don't expect that, so it trips them up a bit. I have a Rev A and I love it, but it's a little hissy compared to the LN versions, like rev D.
|
|
|
Post by tonycamphd on Feb 27, 2014 1:37:36 GMT -6
Just did the calibration on my rev D. Again, this kit is awesome! Except for the physical range of the input/output pots not matching the markings on the faceplate, which I obviously can't fix, I've had zero issues, and having all parts including cables and shrink tubes (and a nice guide on how to twist cables) I managed to make it tidy and clean internally. I don't at all understand the issues some people seem to have over at the 1176 shootout thread. It sounds just great! Compared to Purple and Don Classics rev A on drums and acoustic bass. Very close to the Purple. I believe it had a bit more lo end than the Purple and preferred it on higher input/lightly distorted settings. I'll probably have to go for a rev A eventually Paul=resident DIY animal!!! Nice job man!
|
|