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    LM338 Voltage and Power Questions

    Right on. I had thought about this but will lose half of my 4 amp potential. However, I don't need the 5amp capability of the 338. I also don't realy need the 4 amps from the transformer either. My existing power supply needs a little more than 1 amp, so this may very well reduce my...
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    LM338 Voltage and Power Questions

    Right, but much more conductivity. Any further comments on if a relatively large heat sink can dissipate 16 to maybe 25 watts?
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    LM338 Voltage and Power Questions

    Would it make any sence to mount a TO-220 regulator directly to a heat sink but instead of the mica insulator, insulate the entire heat sink for improved heat conductivity?
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    LM338 Voltage and Power Questions

    Interesting, but I'm afraid this doesn't help me much, as I have purchasedAll the components for two power supplies including the 24v transformers from MPJ and have the voltage and amp meters and cases.
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    LM338 Voltage and Power Questions

    Hi: I am building two LM338 variable regulated voltage supplies for my O-Scale 2-Rail Train Layout. Existing transformers Pull 10-13Volts (full on) at an estimated 1.5 Amps. Due to the circuitry, the existing power supplies cut off at 1.0 Amps, so they run but are a little anemic, more so with...
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    Search for Proven Regulated Power Supply Schematic

    I am looking for a proven working schematic for a 4-5 Amp 0-16Volt DC regulated power supply. I have LM338T regulators purchased from Newark (a TI product) to avoid the Chinese knock-off's with poor reputations. I have 2-3 of the various TI spec. sheets but they leave a lot of detail out. I...
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    LM338K Availability

    Hi Again: After reviewing all options on LM338K non-availability or cheap knock-off's everyone is advising against due to inferior product, I have ordered LM338T's from Newark. Slightly different package but should work. And they are made by Texas Instruments at less than $2.00 each. Thanks...
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    LM338K Availability

    Hi Ylli: Thank you for your kind response. Working with these older and often discontinued items is a little frustrating. Can you advise why you feel the New Egg vendor is the way to go? The LM338K on this web sight has the same SH12AB P/N as many on e-bay. The part is coming from Israel and...
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    LM338K Availability

    I am so afraid of the various potentially knock-off manufacturers of the LM338K. I find them from $1.00 to $60 and that is bulk rate. Here are some of the more reasonable P/N's: SH1035 Sh12AB (Backwards) S H4D0452A H:0512 H4D1602A H1027 S 9442 Philippines Jameco 23835 ST Microelectronics Can...
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    LM338K Availability

    Hi: I am building two regulated DC power supplies for my O-Scale (2 Rail) layout per the LM138/LM338 data sheet. I have built two 1A DC supplies but they are a little anemic for this larger scale system. I have all the parts and components but am afraid of the e-bay LM338K's. One of the 2 is...
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    Voltage Reduction

    OK, Let's start over... Clearly, messing around with the 24V Sola is just not a good idea. Before spending $'s, I like to utilize what I have. I can open up the existing power supply and see if there is anything I can do to stop the buzzing upon long term "ON" time. Possible better idea? 1...
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    Voltage Reduction

    Again: FYI Each TORTOISE will draw 15-16 ma. at stall, so 30 switch machines can be powered by a single 9 or 12 volt, 500 ma. wall plug adapter. Tom
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    Voltage Reduction

    Sorry Guy's: I have read enough of these Forum conversations to realize my information was sorely lacking. I will be using the output to feed Model Railroad panel LED's, 17 Tortoise switch machines that have stall motors and misc. structure lighting, also LED's. The switch machines are...
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    Voltage Reduction

    Hi: Can anyone advise how to obtain 12VDC from a Sola Power supply rated at 24VDC? Thank you... Tom
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    Transformer Search

    I have purchased two conventionally wound 4A transformers for $18e. Not made of money.
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    Transformer Search

    dave9 Regulated power supplies using transformer, bridge and filtered regulator is pretty much standard in the Model Railroad Industry. DCC users may be able to utilize a 12V PSU, as they depend on a digital controller in each locomotive to tap from the full applied voltage to the track. I...
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    Transformer Search

    Thank you Minder. Very interesting. Pricing appears very reasonable for made to orders. I would imagine I could use a larger current stock one of 8,3 Amps (200VA) and that wouldn't adversely effect my need for a 5 Amp or 120 VA transformer. I am assuming that the circuit determines the power...
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    Transformer Search

    Gentlemen and Ladies: Just discovered this fine Forum. This is my first Thread. I am building 5A regulated power supplies for my O-Scale 2-rail layout. I have built two using LM317T regulators but need to increase the power, as the existing ones only deliver a little more than 1 Amp @ 12V...
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