6v & 90v DC Power supply
in [Design]
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From: Joerg on 27 Dec 2005 21:42 Hello Rich, > that about a third of the way down, says: > "... Accurate imitation of the Hammond sound with simple electronic > circuitry was difficult, because the subtly-changing phase relationships > between tonewheels could not be easily replicated...." > > OK, fair enough. :-) > Even with complicated electronics it wasn't. IIRC it was Suzuki-Hammond which came out with the XK2 and then the XK3. Those are pretty elaborate synthesizer organs. But according to the experts it just ain't the same. Regards, Joerg http://www.analogconsultants.com
From: w_tom on 28 Dec 2005 02:20 Buy a DC-DC converter that includes other protection features (ie overvoltage and overcurrent protection) and outputs known parameters (ie ripple voltage). I doubt you will find a single DC-DC converter for both voltages. But a small converter for each voltage should work. Many sources including this one that just arrived on my desk - www.astrodyne.com . BTW, power from automotive systems should also worry about load dump. Technically load dump can be a transient as much as 270 volts on a 12 volt system. In reality, such events may only be 50 volts or less. Transients that would not damage other automotive electronics already designed for this rare and so destructive event. That is a problem with some regulators such as 78xx series. Maximum voltage is typically not sufficient for automotive purposes - would require additional protection. "James F. Mayer" wrote: > Probably good enough for his measly 32 volts. I need to > modify that circuit to work on outputs of 90 volts and 6 volts.
From: Rich Grise on 28 Dec 2005 12:48 On Wed, 28 Dec 2005 02:42:58 +0000, Joerg wrote: > Hello Rich, > >> that about a third of the way down, says: >> "... Accurate imitation of the Hammond sound with simple electronic >> circuitry was difficult, because the subtly-changing phase relationships >> between tonewheels could not be easily replicated...." >> >> OK, fair enough. :-) >> > > Even with complicated electronics it wasn't. IIRC it was Suzuki-Hammond > which came out with the XK2 and then the XK3. Those are pretty elaborate > synthesizer organs. But according to the experts it just ain't the same. > It seems like, no matter how closely you try to mimic the waveform of a real instrument, there's always something that says, "This is electronic." Or, maybe more accurately, "This is not real." ;-) Cheers! Rich
From: Rich Grise on 28 Dec 2005 12:58 On Wed, 28 Dec 2005 02:20:02 -0500, w_tom wrote: On Wed, 28 Dec 2005 02:20:02 -0500, w_tom top-posted: .... > BTW, power from automotive systems should also worry about > load dump. Technically load dump can be a transient as much > as 270 volts on a 12 volt system. In reality, such events may > only be 50 volts or less. Transients that would not damage > other automotive electronics already designed for this rare > and so destructive event. > > That is a problem with some regulators such as 78xx series. > Maximum voltage is typically not sufficient for automotive > purposes - would require additional protection. This is what transzorbs http://www.vishay.com/docs/88301/15ke.pdf and hash chokes are for. I'm not affiliated with Vishay, formerly General Semiconductor, just a satisfied customer. I've used them to protect circuits against the transients caused by a 5 KV arc in an ion gun. :-) Cheers! Rich > > "James F. Mayer" wrote: >> Probably good enough for his measly 32 volts. I need to >> modify that circuit to work on outputs of 90 volts and 6 volts.
From: James F. Mayer on 28 Dec 2005 13:53
"John Crighton" <john_c(a)tpg.com.au> wrote in message news:43b0e5c3.11480811(a)free.teranews.com... > On Tue, 27 Dec 2005 02:02:15 GMT, "James F. Mayer" > <jfma(a)ix.netcom.com> wrote: > >> I need to generate 6v DC and 90v DC from a 12v DC automotive >> electrical >>system to power an RT-70A/GRC surplus military radio. I need about 250 mA >>at +6 volts and about 75 mA at +90 volts. I was thinking about using the >>guts from an old battery back up but it would be a bit of a kluge. Are >>there any 90 volt regulators in the 78xx series? How do I get the voltage >>up to where I can get something that I can get the 90 volts from. Getting >>the 6 volts doesn't seem to be a problem. A 7806 off the battery should >>work for that unless any of you can see a problem doing that. Maybe the >>common common would be a problem. Right now I'm running it off of an >>HP6299A >>and an HP6236B with commons jumpered. I'd like to be able to go portable >>with it. >> >> > Hello again James, > I just came across this site while looking > for something else. > > http://web.telia.com/~u85920178/use/tubepsu.htm > Look at the the 6V AC from 12 V DC. Nifty! > > Here is another > http://www.i4at.org/lib2/inverter.htm > You want DC out so you will have to fit a bridge rectifier > and filter capacitors to the output of the transformer > just like Harry Lythall's circuit above. > > Regards, > John Crighton > Sydney > I'm going to build a modified Lythall but I need to determine what the wattage of the 330 Ohm resisters would be. I'm thinking they should be fairly high. |