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  • #16
    No

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    • #17
      Originally posted by uneumann View Post
      I use them - but ditto++ ^^^^^ on that comment!
      To be clear - I was referring specifically to the units Harold mentioned in the original post.

      That's not to say ALL smps are the same.
      “If you have integrity, nothing else matters. If you don't have integrity, nothing else matters.”
      -Alan K. Simpson, U.S. Senator, Wyoming, 1979-97

      Hofstadter's Law: It always takes longer than you expect, even when you take into account Hofstadter's Law.

      https://sites.google.com/site/stringsandfrets/

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      • #18
        Use 8 batteries then use a few series diodes to reduce the voltage .6/.7 vdc each until you get the supply voltage you want. Keep it simple. You could probably use the same 10 batteries. You would just need more diodes.

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        • #19
          Originally posted by olddawg View Post
          Use 8 batteries then use a few series diodes to reduce the voltage .6/.7 vdc each until you get the supply voltage you want. Keep it simple. You could probably use the same 10 batteries. You would just need more diodes.
          See post #4. Nothing to be gained from more series batteries. More batteries with more diodes just wastes power and batteries.
          Personally I would just use 6 batteries, especially as some of my pedals sound best when supplied with around 8V.
          Last edited by Helmholtz; 04-06-2020, 07:35 PM.
          - Own Opinions Only -

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          • #20
            Originally posted by Helmholtz View Post
            See post #4. Nothing to be gained from more series batteries. More batteries with more diodes just wastes power and batteries.
            Personally I would just use 6 batteries, especially as some of my pedals sound best when supplied with around 8V.
            I was going with what he has. I agree with you as far as batteries in parallel. In series you would get more battery life I think even with the diodes. If it were me I would get one large rechargable battery as close to 10v as I could.

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            • #21
              In series you would get more battery life I think even with the diodes.
              No, the current is determined by the load. Each battery in series is forced to deliver the same current. So more batteries in series will discharge more batteries in the same time.

              Adding more batteries in series does NOT increase total available battery capacity or give more battery life.
              Last edited by Helmholtz; 04-07-2020, 03:05 PM.
              - Own Opinions Only -

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              • #22
                2 battery packs, charge both. Have a switch to choose. Alternate between packs when needed, charge again when needed.

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                • #23
                  Originally posted by Helmholtz View Post
                  See post #4. Nothing to be gained from more series batteries. More batteries with more diodes just wastes power and batteries.
                  Personally I would just use 6 batteries, especially as some of my pedals sound best when supplied with around 8V.
                  I understand what you mean regarding low voltage on some pedals, as a matter of fact I take that concept to an extreme with my Boss DS-1 (ancient Japanese version), and at 7.5vdc or so it sounds awesome. Spits and sputters like no tube amp alone ever could. But it also seems my Boss Chorus and Compressor need the absolute highest voltage to not distort, and the type of distortion they yield on even a half done battery does not generally sound good.

                  So I am left with running everything on 9.8vdc (a really fresh 9v battery voltage), and still run the DS-1 on an almost dead battery. You know, I sometimes wish I wasn't so particular ! But I am.

                  Right now I can run 7 AA IKEA Ladda batteries with plenty of play time to spare, provided I charge them right before the gig. Not too much to ask.

                  But I am also amazed at two things : The lack of really large capacity 9V batteries out there as in 5,000 mAh or more, and the fact that Boss didn't do a better job in insulating the ST-2 amp in a box from power supply ripple.

                  Oh well, just another compromise until something better comes along, or if I can come up with a totally clean high capacity DC source, one that doesn't waste too much heat with a voltage change.
                  Last edited by HaroldBrooks; 04-09-2020, 04:49 AM.
                  " Things change, not always for the better. " - Leo_Gnardo

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                  • #24
                    Originally posted by SoulFetish View Post
                    ... I totally just forgot what I was going to say
                    No worries SoulFetish !

                    It happens to me once every 30 minutes or so, during any conversation these days, but hey, I've always been a bit like that my whole life.

                    I believe they call it "Absent Minded". I've accepted that badge a long time ago ! As long as you can pick up the same idea again at sometime in the future, then you haven't lost your whit.
                    " Things change, not always for the better. " - Leo_Gnardo

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                    • #25
                      Originally posted by Chuck H View Post
                      Bwaaahahahaha...

                      Enjoying your shut in time?

                      Sorry
                      Yes, staying indoors too much supports more dream like thinking for sure, You can make that into a good thing !
                      " Things change, not always for the better. " - Leo_Gnardo

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                      • #26
                        Originally posted by Chuck H View Post
                        I did read "infinite number of odd harmonics", but...

                        Could you run two bucking transformer in series, but out of phase with each other WRT winding direction. I did this with the HF inductor in an attenuator build that would howl whenever single coils were used and you got within nine feet of the thing. It worked a treat for that circumstance.

                        This would allow the original MO of just "more batteries".
                        I have a few of these board, and I will try just that. Thanks for the idea Chuck !
                        " Things change, not always for the better. " - Leo_Gnardo

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                        • #27
                          Originally posted by HaroldBrooks View Post
                          I have a few of these board, and I will try just that. Thanks for the idea Chuck !
                          Something I never did with my own circuit was to measure finite results. In my case (audio frequency) it would have been actual inductance and how much was lost due to mutual inductance. Since I didn't have a "tone" problem I just never got around to it. In your case (supply voltage) it's pretty easy to determine if it works without causing interference, BUT, I think there could be another factor to consider. Just spitballing here, too much mutual inductance might be a source of inefficiency (losses) that could undo any advantage to the greater battery capacity. Not sure how to test for this but I hope somebody chimes in that does.
                          "Take two placebos, works twice as well." Enzo

                          "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

                          "If you're not interested in opinions and the experience of others, why even start a thread?
                          You can't just expect consent." Helmholtz

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                          • #28
                            It seems that any battery system needs some level of custom preparation. I have found the 'easiest and cheapest' basic battery system is based on a 12V VRLA 4Ah or 7Ah battery blocks, as they are used everywhere, and any IT person would have spare or old ones to keep their rack UPS going.

                            They can be charged with any automotive battery charger - I have two 'Aldi' chargers that auto select 6 or 12V and have a small battery setting - they are light as well.

                            Nowadays there are low drop out regulators, so you could custom prepare different power leads for different pedals that operate from nominal 9Vdc - some set down below 9Vdc, and other a bit higher. I could only find cheap eBay linear reg modules based on LM317 in a TO-220 package on a small heatsink with a voltage adjust pot, which have a drop-out voltage of about 2V for around 1A. A quick look indicates the LM317 could be swapped out for something like a LT1086 (also available on ebay), and they have a 1V drop-out, so the battery could discharge to 10V (which is getting pretty flat) and still give 9V output.

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                            • #29
                              Aren't rechargeable AA's still NiCad? The problem with those is that it's possible to mess up their capacity with improper charging. They have to be drained all the way to dead and then charged or else their full charge level changes. Or at least I've read something like that. Maybe we have a battery expert here that could clarify. Li ion's don't do this and you can buy all sorts of compact cell combinations and impressive AH figures. They're not cheap, but it's a tool you're going to use. The real advantage with li ion's is that they can be plugged into the charger from any state of charge without risk of damage. That way you could always be sure you have a fresh charge before a gig.
                              "Take two placebos, works twice as well." Enzo

                              "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

                              "If you're not interested in opinions and the experience of others, why even start a thread?
                              You can't just expect consent." Helmholtz

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                              • #30
                                Could you run two bucking transformer in series, but out of phase with each other WRT winding direction.
                                For some compensation of radiated EMI with two buck converters, the HF switching would have to be synchronized.
                                - Own Opinions Only -

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