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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#41
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Dropping 1V from a Regulated 6V Wall Wart
On Tue, 30 Dec 2003 08:28:53 -0800, Watson A.Name - "Watt Sun, Dark
Remover" wrote: In article , mentioned... On Tue, 30 Dec 2003 12:36:45 GMT, Active8 ,invalid wrote: Rough guess... ---+------------------+ | | | 10 | | ___ |/ +---|___|---+----| | | | | - | 5.6 500mW ^ +--------- | -------------+---------------- --- Closer guess: Ib ~ Ie/ß = 200mA/100 = 2mA IZt = 20mA R = (Vin-VZ)/(IZt+Ib) = 0.4V/0.022A = 18.18...R ~ 20R Yeah, I was thinking something really low like that. But these approaches have been to establish a new regulated voltage, dependent on the value of the zener. There's nothing wrong with this, but it would be simpler to just use a LDO 5V regulator as someone suggested. --- I agree. Plus, you won't have the Zener tempco and delta VZ/delta IZ (small though it might be since the change in IZ will only be caused by the change in the transistor's Ib as the load current goes from 0mA to 200mA) to contend with. And, a BIG plus for the LDO, you won't be dissipating the power the Zener will be _all the time_ , regardless of the load current. -- John Fields |
#42
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Dropping 1V from a Regulated 6V Wall Wart
On Tue, 30 Dec 2003 16:54:34 GMT, Active8
,invalid wrote: On Tue, 30 Dec 2003 08:57:09 -0600, said... On Tue, 30 Dec 2003 12:36:45 GMT, Active8 ,invalid wrote: Rough guess... ---+------------------+ | | | 10 | | ___ |/ +---|___|---+----| | | | | - | 5.6 500mW ^ +--------- | -------------+---------------- --- Closer guess: Ib ~ Ie/ß = 200mA/100 = 2mA IZt = 20mA R = (Vin-VZ)/(IZt+Ib) = 0.4V/0.022A = 18.18...R ~ 20R Ok, I incorrectly guessed Beta (Chaos Master told me how to get special characters and it doesn't work here) of 200 and set Iz at 40mA (a waste) to get the 500mW zener to operate at about half it's rating. I know, I only needed 10mA if Ib really were 10mA. --- Any common 5.6V 500mW Zener will have its Zener voltage specified at a particular test current; 20mA. This current is what _must_ flow through the Zener in order for the reverse voltage it drops to fall within the bounds specified. 40mA will not only waste 20mA, it could cause the Zener voltage to be out of spec. The beta of the transistor (more properly the alpha) is almost unimportant in this case since the base current will be very small compared to the collector/emitter current and its change will have very little impact on the Zener current from no-load to full-load. -- John Fields |
#43
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Dropping 1V from a Regulated 6V Wall Wart
On Mon, 29 Dec 2003 23:50:26 GMT, Active8
,invalid wrote: Ah! So, you mean R2 = 5*R1 or 5.R1 in K.A. notation. --- The meaning was adequately clear; JW (to his credit) just likes to play, sometimes. -- John Fields |
#44
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Dropping 1V from a Regulated 6V Wall Wart
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#46
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Dropping 1V from a Regulated 6V Wall Wart
I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth
link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: Ok, I incorrectly guessed Beta (Chaos Master told me how to get special characters and it doesn't work here) Doesn't ALT0223 on the numeric keypad, with Num Lock on, work? ßßß -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
#47
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Dropping 1V from a Regulated 6V Wall Wart
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#48
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Dropping 1V from a Regulated 6V Wall Wart
I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth
link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: ok 03b0 is for arial and 0223 is for courier. No, this is "Windows 'extended ASCII' characters", not Unicode and 0223 works for any font that contains the character. There are two different series; one of the form 'ALT1nn'and 'ALT2nn', which are in no logical order and the other in the series ALT0128 (which is ‚¬, the Euro symbol) to ALT0255 (which is ÿ). Not all of the characters will show on the screen. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
#49
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Dropping 1V from a Regulated 6V Wall Wart
On Tue, 30 Dec 2003 18:49:15 GMT, Active8
,invalid wrote: On Tue, 30 Dec 2003 12:25:36 -0600, said... On Mon, 29 Dec 2003 23:50:26 GMT, Active8 ,invalid wrote: Ah! So, you mean R2 = 5*R1 or 5.R1 in K.A. notation. --- The meaning was adequately clear; Yes. It's been fun. I love this groups sense of humor. JW (to his credit) just likes to play, sometimes. And I also like to play. See what I mean? I didn't spell out what I meant or add an emoticon, and *my* meaning wasn't clear. --- Not by choice, I suspect. ;-) -- John Fields |
#50
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Dropping 1V from a Regulated 6V Wall Wart
On Tue, 30 Dec 2003 19:15:58 +0000, John Woodgate
wrote: I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: Ok, I incorrectly guessed Beta (Chaos Master told me how to get special characters and it doesn't work here) Doesn't ALT0223 on the numeric keypad, with Num Lock on, work? ßßß --- You ß believe it! On mine, with NUMLOCK off, ALT 225 = ß, and ALT 223 = ¯ while ALT 0225 = á and ALT 0223 = ß with NUMLOCK on, ALT 225 = ß and ALT 223 = ¯ while ALT 0225 = á and ALT 0223 = ß -- John Fields |
#51
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Dropping 1V from a Regulated 6V Wall Wart
On Tue, 30 Dec 2003 15:38:21 -0600, John Fields
wrote: On Tue, 30 Dec 2003 19:15:58 +0000, John Woodgate wrote: I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: Ok, I incorrectly guessed Beta (Chaos Master told me how to get special characters and it doesn't work here) Doesn't ALT0223 on the numeric keypad, with Num Lock on, work? ßßß --- You ß believe it! On mine, with NUMLOCK off, ALT 225 = ß, and ALT 223 = ¯ while ALT 0225 = á and ALT 0223 = ß with NUMLOCK on, ALT 225 = ß and ALT 223 = ¯ while ALT 0225 = á and ALT 0223 = ß Wow! That's a BIG difference ;-) ...Jim Thompson -- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice480)460-2350 | | | E-mail Address at Website Fax480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
#52
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Dropping 1V from a Regulated 6V Wall Wart
On Tue, 30 Dec 2003 15:20:04 -0600,
said... On Tue, 30 Dec 2003 18:49:15 GMT, Active8 ,invalid wrote: On Tue, 30 Dec 2003 12:25:36 -0600, said... On Mon, 29 Dec 2003 23:50:26 GMT, Active8 ,invalid wrote: Ah! So, you mean R2 = 5*R1 or 5.R1 in K.A. notation. --- The meaning was adequately clear; Yes. It's been fun. I love this groups sense of humor. JW (to his credit) just likes to play, sometimes. And I also like to play. See what I mean? I didn't spell out what I meant or add an emoticon, and *my* meaning wasn't clear. --- Not by choice, I suspect. ;-) Of course not. See my email addy? It says invalid I don't try to foul things up, that'd be masochistic. -- Best Regards, Mike |
#53
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Dropping 1V from a Regulated 6V Wall Wart
Isn't that too practical and simple?
Bob (Wade Hassler) wrote: I did this a while back. Replaced the 7806 in the wall wart with a 7805. Wade |
#54
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Dropping 1V from a Regulated 6V Wall Wart
On Tue, 30 Dec 2003 21:16:42 +0000,
said... I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: ok 03b0 is for arial and 0223 is for courier. No, this is "Windows 'extended ASCII' characters", not Unicode and 0223 works for any font that contains the character. There are two different series; one of the form 'ALT1nn'and 'ALT2nn', which are in no logical order and the other in the series ALT0128 (which is ‚¬, the Euro symbol) to ALT0255 (which is ÿ). Not all of the characters will show on the screen. OK it does work in note tab lite regardless of font. What I meant was that if I'm looking up the code in character map, it changes for different fonts. It *does* say Unicode, also. So I don't have an extended ascii chart. ok. Nothing on MSDN CD. As usual, google rules when you know what to look for. http://www.cdrummond.qc.ca/cegep/inf.../Alain/files/a scii.htm says 225 is beta so does this: http://www.jimprice.com/ascii-128-255.gif are we having fun yet? ok 225 is beta in the alt2nn series and 223 is a bar. alt0223 is a box. That second link came from http://www.jimprice.com/jim-asc.htm which has a lot of possibly useful links. Thanks John, -- Best Regards, Mike |
#56
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Dropping 1V from a Regulated 6V Wall Wart
"Wade Hassler" wrote in message om... Watson A.Name - "Watt Sun, Dark Remover" wrote in message om... I needed to drop 1V from a 6VDC 200 mA regulated wall wart, so I tried a 3 amp rectifier, but it varied by more than .2V over a range of loads. So I tried this: (view with courier font) + From wall wart --+ | +---+------+ | | | | 400 \ / 2SC2334 or TIP31 ohm / |/ NPN power TO-220 WW \-----| Heatsink optional pot / |\ | E\ | | | | +----+-----+ | | +------ + output to load - -------------- - From wall wart This has some advantages and disadvantages. It's simple and cheap, and keeps the output at 5V within a tenth of a volt over a current range. But it has a minimum current below which it loses regulation and the output starts to go up to 6V, because the transistor is not conducting and the current is being supplied thru the ww pot. This circuit is sometimes used in the bias circuit for the output transistors in high powered amplifiers. Also Win Hill showed us here how to use a similar circuit to maintain the voltage steady for a current regulator circuit used on four AA cell rechargeable batteries. I'm thinking about putting a 5.1V zener on the output so that if the voltage climbs above that, it just shunts the excess current. Oh, yeah, I set the pot to various values to see what the output voltage was with various loads. The two resistances were 120 ohms for the upper and 280 ohms for the lower. I suppose the 400 ohms total could be raised to a higher value, but the transistor needs enough base current to do its job. There's only 1V available minus the .6V E-B voltage, so even at 400 ohms, that's not a lot of current. -- @@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@ h@e@r@e@@ ###Got a Question about ELECTRONICS? Check HERE First:### http://users.pandora.be/educypedia/e...s/databank.htm My email address is whitelisted. *All* email sent to it goes directly to the trash unless you add NOSPAM in the Subject: line with other stuff. alondra101 at hotmail.com Don't be ripped off by the big book dealers. Go to the URL that will give you a choice and save you money(up to half). http://www.everybookstore.com You'll be glad you did! Just when you thought you had all this figured out, the gov't changed it: http://physics.nist.gov/cuu/Units/binary.html @@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@ u@e@n@t@@ I did this a while back. Replaced the 7806 in the wall wart with a 7805. Wade Too easy Wade!....But still an interesting thread! |
#57
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Dropping 1V from a Regulated 6V Wall Wart
htmlß/html
ß is 223 decimal in the latin1 supplement... http://www.unicode.org/charts/PDF/U0080.pdf |
#58
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Dropping 1V from a Regulated 6V Wall Wart
I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth
link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: So I don't have an extended ascii chart. ok. Nothing on MSDN CD. As usual, google rules when you know what to look for. http://www.cdrummond.qc.ca/cegep/inf.../Alain/files/a scii.htm says 225 is beta so does this: http://www.jimprice.com/ascii-128-255.gif are we having fun yet? ok 225 is beta in the alt2nn series and 223 is a bar. alt0223 is a box. No. Both of your links give a DIFFERENT 'extended ASCII' series, not the Windows one. There is no standard for 'extended ASCII', so there are several different versions around. I found the Windows list in an early WordPerfect manual. But you can compile your own by just typing in the codes and noting the result. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
#59
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Dropping 1V from a Regulated 6V Wall Wart
I read in sci.electronics.design that John Fields jfields@austininstrum
ents.com wrote (in ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: You ß believe it! On mine, with NUMLOCK off, ALT 225 = ß, and ALT 223 = ¯ while ALT 0225 = á and ALT 0223 = ß with NUMLOCK on, ALT 225 = ß and ALT 223 = ¯ while ALT 0225 = á and ALT 0223 = ß You need Num Lock on with some versions of Windows but with others it can be on or off. ON always works, AFAIK. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
#60
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Dropping 1V from a Regulated 6V Wall Wart
In article , mentioned...
Watson A.Name - Watt Sun, Dark Remover wrote: I needed to drop 1V from a 6VDC 200 mA regulated wall wart, so I tried a 3 amp rectifier, but it varied by more than .2V over a range of loads. So I tried this: (view with courier font) + From wall wart --+ | +---+------+ | | | | 400 \ / 2SC2334 or TIP31 ohm / |/ NPN power TO-220 WW \-----| Heatsink optional pot / |\ | E\ | | | | +----+-----+ | | +------ + output to load - -------------- - From wall wart This has some advantages and disadvantages. It's simple and cheap, and keeps the output at 5V within a tenth of a volt over a current range. But it has a minimum current below which it loses regulation and the output starts to go up to 6V, because the transistor is not conducting and the current is being supplied thru the ww pot. This circuit is sometimes used in the bias circuit for the output transistors in high powered amplifiers. Also Win Hill showed us here how to use a similar circuit to maintain the voltage steady for a current regulator circuit used on four AA cell rechargeable batteries. I'm thinking about putting a 5.1V zener on the output so that if the voltage climbs above that, it just shunts the excess current. Oh, yeah, I set the pot to various values to see what the output voltage was with various loads. The two resistances were 120 ohms for the upper and 280 ohms for the lower. I suppose the 400 ohms total could be raised to a higher value, but the transistor needs enough base current to do its job. There's only 1V available minus the .6V E-B voltage, so even at 400 ohms, that's not a lot of current. I've tried to do this on numerous occasions. If you need any amount of current at all, the big lump of stuff makes it too unweildy, even if you do bite the bullet and put in a complex circuit that works. Now, for regulated warts, I crack the case and shunt a resistor inside the wall wart. You can add a switch if you have multiple applications. If you need both voltages at once, it's still easier to use two warts than to have this lump of regulator stuff hanging about. I'm a little confused by your requirements. If you even considered a diode, you can't be too concerned about the actual voltage...but you're concerned about the .2V variability. Sounds like there's something in there that's important but not disclosed??? mike Well, I started out in this or another thread with a RF modulator that requires 4.75 to 5.25VDC, probably because it would be off freq if the supply V got out of tolerance. I talked about the weird connector, someone said it's a Belling Lee connector, AKA Euro or PAL connector. Now I now what it is, and I bot an adapter at Rat Shack for four bucks. But I wanted something simple that I could solder onto the pins of the RF modulator, I finally resolved the problem by using a 6V unregulated wall wart, which is more like 7 or 8V, and a 5.1V zener, and 39 ohm resistor as a shunt regulator. It works just fine. But I still wanted a way to drop a single volt, with reasonable regulation, better than a 1N4003 diode which varies by up to a quarter volt. With a 1N4003 the voltage could be as high as 5.3 or 5.4V. -- @@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@ h@e@r@e@@ ###Got a Question about ELECTRONICS? Check HERE First:### http://users.pandora.be/educypedia/e...s/databank.htm My email address is whitelisted. *All* email sent to it goes directly to the trash unless you add NOSPAM in the Subject: line with other stuff. alondra101 at hotmail.com Don't be ripped off by the big book dealers. Go to the URL that will give you a choice and save you money(up to half). http://www.everybookstore.com You'll be glad you did! Just when you thought you had all this figured out, the gov't changed it: http://physics.nist.gov/cuu/Units/binary.html @@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@ u@e@n@t@@ |
#61
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Dropping 1V from a Regulated 6V Wall Wart
I read in alt.binaries.schematics.electronic that Watson A. Name - Watt
Sun, Dark Remover wrote (in MPG.1a5cbb112ab587 ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Wed, 31 Dec 2003: I talked about the weird connector, someone said it's a Belling Lee connector, That's a coaxial connector, a bit like a phono plug but with a smaller centre pin. Is that what you have? AKA Euro or PAL connector. I'd forget those descriptions if I were you. Certainly the Belling connector has very little indeed to do with PAL. It is the subject of an IEC standard - IEC 60169-2. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
#62
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Dropping 1V from a Regulated 6V Wall Wart
Watson A.Name - Watt Sun, Dark Remover wrote:
I needed to drop 1V from a 6VDC 200 mA regulated wall wart, so I tried a 3 amp rectifier, but it varied by more than .2V over a range of loads. So I tried this: (view with courier font) + From wall [edited for brevity] wart --+---+-----+ | | | | 400 \ / 2SC2334 or TIP31 ohm / |/ NPN power TO-220 WW \-----| Heatsink optional pot / |\ | E\ | | | | +----+----+---- + output to load - ----------------- - Hmm, a complementary-darlington emitter-follower transistor would be less sensitive to changes in load current: : +6.0V, from wall wart : --+--------+------+ : | | | : | 220 | Q1 2sa1011 : | | |/E pnp TIP32 : | +----| etc : | | |\ : 1.0k |/ | : pot ---| Q2 | : | |\E npn | : | | | : 7.5k +------+----- + output : | to load : - --+--------------------- - Here the Q2 voltage drop is much more predictable, because it has a relatively steady current set by Q1's base-emitter resistor, which has about 0.55 to 0.75V across it despite output load changes. The Q2 current is about 3 - 5mA and we expect a Vbe drop of about 700mV. The lower end of the pot sits at about 5.3 volts. The most serious problem with this circuit is its complete reliance on a possibly-uncertain input voltage; the output will track any changes in input. analyzed Watson A. Name's circuit: You almost had it- put the Vbe multiplier inside the feedback loop and buffer like so: 6V ---+------+-------+ [edited for brevity] | | | | 22 c | | |/ Q1 | +-----| TIP31 | | |\ == | e---+----+---- 5V | c Q2 | | | \| / | | |------- \ | | /| / === | e | 1000U | | | | GND --+------+-----------+----+---- GND Watson A.Name - Watt Sun, Dark Remover asked: I'll toss one together, but what value should I use for the Pot? 10k? Lower? This looks a lot like the current limiter circuit, 'cept for the pot. No, it's an ordinary regulator, using Q2's Vbe (roughly 0.7V) as a voltage reference. The pot as shown would be a poor choice because valid adjustments would only use a small part of the pot's range. No doubt nospam knew that and was just simplifying his drawing by using one part instead of three. This should work; the top of the pot has about 0.82V when the regulator is calibrated for 5V out: | | ---+---- 5V | | | === | ,-2k2--+ | c Q2 | | | \| 100R | | |---- pot | | /| | === | e 330 1000U | | | | GND --+------+---------+------+---- GND This circuit has several problems. The tempco of Vbe is bad, but the uncertain current through Q2 an even worse problem. This is because the voltage difference between the +6V input and Q1's base is small (and may vary widely), and Q1's base current is unknown. If Q2's current changes by a factor of 10, its Vbe will change by about 60mV, or nearly 10% of its value. As a result Q2 makes a poor voltage reference in this circuit, even if manually adjusted. I'm wondering if it's such a good idea to have such a large cap on the output. When the wall wart is powered off, all that current tries to go backwards thru the pass transistor. A big cap is fine, maybe even necessary in that location, because a small output cap could make the feedback loop unstable. We discuss this issue in AoE and call it brute-force compensation. The current won't go backwards for several reasons. The wall wort probably doesn't draw output terminal current when the AC is off. If it wanted to, Q1's Veb breakdown would certainly be above 5V so no current would flow anyway. Jim Thompson wrote... Try this... + From wall [edited for brevity] wart --+---+-----+ | | 20 Q1 | | / 2SC2334 or TIP31 | |/ NPN power TO-220 o------| Heatsink optional | |\ | E\ | | | o----- + output | | to load __|___/ 2.2k / /\ | / \-------o / \ | -------- 2.7k | TL430 | | | - ------o---------o------ - You may need a compensation cap between cathode and control pin. This is a much better approach, using TL430's 2.75V reference with a built-in error amplifier. The more popular TL431 can be used with its 2.50V ref if the feedback-sensing resistors are the same value. But I'm not happy with the output emitter follower in the circuits above, because the low Vin - Vout difference leads to such widely- varying currents through the control element. Perhaps my circuit can be combined with Jim's circuit: : +6.0V, from wall wart : --+------+------+ : | | | : | 220 | Q1 2sa1011 : | | |/E pnp TIP32 : 750 +----| etc : | | |\ : | |/ | : +----| Q2 | : | |\E npn | : | | | : | +---+--+---- + output | | to load __|___/ 2.7k / /\ | / \--------o / \ | -------- 2.7k | TL431 | | | - ----o----------o------- - Thanks, - Win whill_at_picovolt-dot-com |
#63
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Dropping 1V from a Regulated 6V Wall Wart
Winfield Hill wrote...
Perhaps my circuit can be combined with Jim's circuit: : +6.0V, from wall wart : --+------+------+ : | | | : | 220 | Q1 2sa1011 : | | |/E pnp TIP32 : 750 +----| etc : | | |\ : | |/ | : +----| Q2 | : | |\E npn | : | | | : | +---+--+---- + output | | to load __|___/ 2.7k / /\ | / \--------o / \ | -------- 2.7k | TL431 | | | - ----o----------o------- - I'm still not happy with the poor dropout-voltage capability of this circuit. It should be able to operate with Vin much closer to Vout. Aha! Simply adding a diode and resistor lets us reduce the dropout voltage down to near the saturation voltage of Q1. : +5.3 to 9V : --+-----+------, SIMPLE 5.0V REGULATOR : | | | : | 220 | Q1 2sa1011 : | | |/E pnp TIP32 : 470 o----| etc : | | |\ : | |/ | : o---| Q2 '----o---- +5.0V : | |\E npn | output : | | | to load : | | 1n4148 | : | '--o--||---o | | | __|___/ 1k 2.7k / /\ | | / \----- | -------o / \ | | -------- | 2.7k | TL431 | | | | | - ----o--------o--------o---- - Of course, an even more simple circuit is possible, using one of the many low-cost low-dropout three-terminal regulator ICs. : +5.3 to 9V etc : -------, EVEN MORE SIMPLE 5.0V REGULATOR : __|__ : | | : | |---+--- +5.0V : |_____| _|_ output : | --- to load : | | : - -------o------o--- - But this circuit isn't as much fun. :) Thanks, - Win whill_at_picovolt-dot-com |
#64
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Dropping 1V from a Regulated 6V Wall Wart
In article ,
mentioned... I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: Ok, I incorrectly guessed Beta (Chaos Master told me how to get special characters and it doesn't work here) Doesn't ALT0223 on the numeric keypad, with Num Lock on, work? ßßß This alt 0233 -- é looks to me like it's an accented e, as in Jose' What's it look like to you? -- @@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@ h@e@r@e@@ ###Got a Question about ELECTRONICS? Check HERE First:### http://users.pandora.be/educypedia/e...s/databank.htm My email address is whitelisted. *All* email sent to it goes directly to the trash unless you add NOSPAM in the Subject: line with other stuff. alondra101 at hotmail.com Don't be ripped off by the big book dealers. Go to the URL that will give you a choice and save you money(up to half). http://www.everybookstore.com You'll be glad you did! Just when you thought you had all this figured out, the gov't changed it: http://physics.nist.gov/cuu/Units/binary.html @@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@ u@e@n@t@@ |
#65
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Dropping 1V from a Regulated 6V Wall Wart
On Wed, 31 Dec 2003 14:29:34 -0800, Watson A.Name - "Watt Sun, Dark
Remover" said... In article , mentioned... I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: Ok, I incorrectly guessed Beta (Chaos Master told me how to get special characters and it doesn't work here) Doesn't ALT0223 on the numeric keypad, with Num Lock on, work? ßßß This alt 0233 -- é looks to me like it's an accented e, as in Jose' What's it look like to you? An e with a single dot over it, not the accent mark as in Jose'. I think it's one of those pronunciation symbols. -- Best Regards, Mike |
#66
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Dropping 1V from a Regulated 6V Wall Wart
On Wed, 31 Dec 2003 19:37:12 +0000,
said... I read in alt.binaries.schematics.electronic that Watson A. Name - Watt Sun, Dark Remover wrote (in MPG.1a5cbb112ab587 ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Wed, 31 Dec 2003: I talked about the weird connector, someone said it's a Belling Lee connector, That's a coaxial connector, a bit like a phono plug but with a smaller centre pin. Is that what you have? AKA Euro or PAL connector. I'd forget those descriptions if I were you. Certainly the Belling connector has very little indeed to do with PAL. It is the subject of an IEC standard - IEC 60169-2. It looks (the outer part) exactly like one of those RS push on F connectors - the male one (male center conductor, female housing) but the center conductor is hollow and split as if the mating connector would compress it and cause it to seize the mating connector's center conductor which in that case would make the CIQ (connector in question) female and female no thread. I couldn't quite get a real idea of the size from the photo. Let's check Pasternack. The PAL connector in this book is a push on, but the CIQ can't be this PAL connector. The one I'm looking at is male-female into female-male with the male housing (which would correspond to the CIQ) is .370" OD. I see 75 ohm MCX connectors where the jack corresponding to the CIQ accepts a plug with a .147" OD housing - seisure and all. I'd replace the friggin' thing with something I can lay hands on easily. F connectors are common enough. Push ons I only use for testing. -- Best Regards, Mike |
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Dropping 1V from a Regulated 6V Wall Wart
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Dropping 1V from a Regulated 6V Wall Wart
Winfield Hill wrote: Winfield Hill wrote... Perhaps my circuit can be combined with Jim's circuit: : +6.0V, from wall wart : --+------+------+ : | | | : | 220 | Q1 2sa1011 : | | |/E pnp TIP32 : 750 +----| etc : | | |\ : | |/ | : +----| Q2 | : | |\E npn | : | | | : | +---+--+---- + output | | to load __|___/ 2.7k / /\ | / \--------o / \ | -------- 2.7k | TL431 | | | - ----o----------o------- - I'm still not happy with the poor dropout-voltage capability of this circuit. It should be able to operate with Vin much closer to Vout. Aha! Simply adding a diode and resistor lets us reduce the dropout voltage down to near the saturation voltage of Q1. : +5.3 to 9V : --+-----+------, SIMPLE 5.0V REGULATOR : | | | : | 220 | Q1 2sa1011 : | | |/E pnp TIP32 : 470 o----| etc : | | |\ : | |/ | : o---| Q2 '----o---- +5.0V : | |\E npn | output : | | | to load : | | 1n4148 | : | '--o--||---o | | | __|___/ 1k 2.7k / /\ | | / \----- | -------o / \ | | -------- | 2.7k | TL431 | | | | | - ----o--------o--------o---- - Of course, an even more simple circuit is possible, using one of the many low-cost low-dropout three-terminal regulator ICs. : +5.3 to 9V etc : -------, EVEN MORE SIMPLE 5.0V REGULATOR : __|__ : | | : | |---+--- +5.0V : |_____| _|_ output : | --- to load : | | : - -------o------o--- - But this circuit isn't as much fun. :) Thanks, - Win whill_at_picovolt-dot-com If you want a 1V drop (for some reason???) then something like this: Please view in a fixed-width font such as Courier. LM185-ADJ \ +---------| |---------+ | \ | | | +------+-------------------------+ | | | | | / | | | 470 | | | / | | | TIP42 \ | | Vin----+-------- e c ---+-------+-----------------------Vout | \ / | | | | --- | | c | 10K | 1N4148 | | 10K |/ +----/\/\---+---||----+ +--/\/\-----+---| | | |\ | c e | \| | | |---+ | /| | / e / 470 | 1.3K / | / \ | \ | | | --- --- --- |
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Dropping 1V from a Regulated 6V Wall Wart
I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth
link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Thu, 1 Jan 2004: An e with a single dot over it, not the accent mark as in Jose'. I think it's one of those pronunciation symbols. The dot instead of a proper accent is a feature of whatever font you are using. Look at it in Courier, Arial, Times New Roman. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
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Dropping 1V from a Regulated 6V Wall Wart
I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth
link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Thu, 1 Jan 2004: It looks (the outer part) exactly like one of those RS push on F connectors - the male one (male center conductor, female housing) but the center conductor is hollow and split as if the mating connector would compress it and cause it to seize the mating connector's center conductor which in that case would make the CIQ (connector in question) female and female no thread. I couldn't quite get a real idea of the size from the photo. Let's check Pasternack. You've described a Belling coax connector, I think. I don't know what Pasternack is; a connector distributor? The PAL connector in this book is a push on, but the CIQ can't be this PAL connector. The one I'm looking at is male-female into female-male with the male housing (which would correspond to the CIQ) is .370" OD. I just don't recognize the term 'PAL connector'. I see 75 ohm MCX connectors where the jack corresponding to the CIQ accepts a plug with a .147" OD housing - seisure and all. I'd replace the friggin' thing with something I can lay hands on easily. F connectors are common enough. Push ons I only use for testing. You should be able to get Belling-type connectors from Farnell/Newark. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
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Dropping 1V from a Regulated 6V Wall Wart
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Dropping 1V from a Regulated 6V Wall Wart
On Wed, 31 Dec 2003 14:29:34 -0800, Watson A.Name - "Watt Sun, Dark
Remover" said... In article , mentioned... I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: Ok, I incorrectly guessed Beta (Chaos Master told me how to get special characters and it doesn't work here) Doesn't ALT0223 on the numeric keypad, with Num Lock on, work? ßßß This alt 0233 -- é looks to me like it's an accented e, as in Jose' What's it look like to you? ------------------------ Hey Watson. You accidentally typed alt 0233 as you said instead of alt 0223 like John said Also, measure your connector & see if that MX 75 O [ == this little omega looks like a zero. arrrggghhh! No HTML in NNTP either.] connector I posted the OD on is close. And if you look back to the link I posted on these extended ascii codes and other useful (?) links, you'll see a connector reference link near the top. ----------------------- -- Best Regards, Mike |
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Dropping 1V from a Regulated 6V Wall Wart
On Thu, 1 Jan 2004 07:24:00 +0000,
said... I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Thu, 1 Jan 2004: It looks (the outer part) exactly like one of those RS push on F connectors - the male one (male center conductor, female housing) but the center conductor is hollow and split as if the mating connector would compress it and cause it to seize the mating connector's center conductor which in that case would make the CIQ (connector in question) female and female no thread. I couldn't quite get a real idea of the size from the photo. Let's check Pasternack. You've described a Belling coax connector, I think. I don't know what Pasternack is; a connector distributor? Yes. www.pasternack.com It seems like they replace my catalog every month. They have a UK disty: www.spectech.dial.pipex.com The PAL connector in this book is a push on, but the CIQ can't be this PAL connector. The one I'm looking at is male-female into female-male with the male housing (which would correspond to the CIQ) is .370" OD. I just don't recognize the term 'PAL connector'. I thought PAL was/is (it is) a Europeeeen video standard. But there is a PAL connector in the cat sure enough and it ain't what Watson's got. I see 75 ohm MCX connectors where the jack corresponding to the CIQ accepts a plug with a .147" OD housing - seisure and all. ---------------------- I'd replace the friggin' thing with something I can lay hands on easily. F connectors are common enough. Push ons I only use for testing. ---------------------- You should be able to get Belling-type connectors from Farnell/Newark. That's a good source for a lot of stuff. In Baltimore there's Bainsville Electronics which is great, but I've only seen gold- plated *kits* in the showcase. I'd wager they have it though. -- Best Regards, Mike |
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Dropping 1V from a Regulated 6V Wall Wart
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Dropping 1V from a Regulated 6V Wall Wart
I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth
link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Thu, 1 Jan 2004: I thought PAL was/is (it is) a Europeeeen video standard. Indeed it is; it's the whole phrase 'PAL connector' that I don't recognize. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! |
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Dropping 1V from a Regulated 6V Wall Wart
Hmm. When I hit alt-0233, I get one of these: !
Cheers! Rich "Watson A.Name - Watt Sun, Dark Remover" wrote in message m... In article , mentioned... I read in sci.electronics.design that Active8 mTHISREMOVEcolasono@earth link.net wrote (in t ) about 'Dropping 1V from a Regulated 6V Wall Wart', on Tue, 30 Dec 2003: Ok, I incorrectly guessed Beta (Chaos Master told me how to get special characters and it doesn't work here) Doesn't ALT0223 on the numeric keypad, with Num Lock on, work? ßßß This alt 0233 -- é looks to me like it's an accented e, as in Jose' What's it look like to you? -- @@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@ h@e@r@e@@ ###Got a Question about ELECTRONICS? Check HERE First:### http://users.pandora.be/educypedia/e...s/databank.htm My email address is whitelisted. *All* email sent to it goes directly to the trash unless you add NOSPAM in the Subject: line with other stuff. alondra101 at hotmail.com Don't be ripped off by the big book dealers. Go to the URL that will give you a choice and save you money(up to half). http://www.everybookstore.com You'll be glad you did! Just when you thought you had all this figured out, the gov't changed it: http://physics.nist.gov/cuu/Units/binary.html @@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@ u@e@n@t@@ |
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Dropping 1V from a Regulated 6V Wall Wart
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Dropping 1V from a Regulated 6V Wall Wart
On Fri, 02 Jan 2004 02:09:44 GMT, Active8
,invalid wrote: On Fri, 02 Jan 2004 01:02:45 GMT, said... Hmm. When I hit alt-0233, I get one of these: ! Cheers! Rich I can say with cetainty that I received an exclaimation point. Hopeless? Maybe not. If what I received is what you sent then the same code is displaying the same character on the screen on both ends. JW and I seem to have the same settings (odd because he said he used winders 98), but you either have your locale set differently or something I haven't though of. I'm set for English(United State) - Regional and Language settings in control panel. Character map isn't working here for omega so I'd better blow it off. alt-0233 = é with NumLock ON or OFF, Win2K machine ...Jim Thompson -- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice480)460-2350 | | | E-mail Address at Website Fax480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
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Dropping 1V from a Regulated 6V Wall Wart
"Active8" ,invalid wrote in message k.net... On Fri, 02 Jan 2004 01:02:45 GMT, said... Hmm. When I hit alt-0233, I get one of these: ! Cheers! Rich I can say with cetainty that I received an exclaimation point. Hopeless? Maybe not. If what I received is what you sent then the same code is displaying the same character on the screen on both ends. JW and I seem to have the same settings (odd because he said he used winders 98), but you either have your locale set differently or something I haven't though of. I'm set for English(United State) - Regional and Language settings in control panel. Character map isn't working here for omega so I'd better blow it off. -- Best Regards, Mike Don't type the leading zero unless it's a 2 digit code, ASCII codes are all 3 digit from 000 to 255. |
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Dropping 1V from a Regulated 6V Wall Wart
In article ,
mentioned... [snip] I did this a while back. Replaced the 7806 in the wall wart with a 7805. Wade Yeah, but I've got four or five of them and I didn't want to crack them open and then have to deal with the hassles of a case that's no longer solidly sealed. And besides, they were only two bucks apiece. I may bave paid more for their shipping. Also, I bot four of the 6VDC unregulated wall warts at the same time, and they have about 7 or 8V output unloaded. I don't think they have enough voltage to allow a 7805 to work properly, at least not up to 200 mA, because the DC voltage drops down to near 6V at that current. But 6VDC is a convenient value, used by a lot of equipment that has four AA cells. So I have them just in case I want to 'electrify' one of those ol' radios or whatever. -- @@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@ h@e@r@e@@ ###Got a Question about ELECTRONICS? Check HERE First:### http://users.pandora.be/educypedia/e...s/databank.htm My email address is whitelisted. *All* email sent to it goes directly to the trash unless you add NOSPAM in the Subject: line with other stuff. alondra101 at hotmail.com Don't be ripped off by the big book dealers. Go to the URL that will give you a choice and save you money(up to half). http://www.everybookstore.com You'll be glad you did! Just when you thought you had all this figured out, the gov't changed it: http://physics.nist.gov/cuu/Units/binary.html @@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@ u@e@n@t@@ |
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