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  1. D

    Simple lamps circuit

    Is this a student exercise ? I suggest using Arduino Nano or Uno board. You would hook up leds to port pins like this : Use a R of ~ 170 ohms. Then use mBlock to code the Arduino. Here is a training video - Regards, Dana.
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    Simple lamps circuit

    What tools do you have, a vollt/ammeter, a soldering iron, a breadboard......?
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    Simple lamps circuit

    Consider doing this project first with LEDs as lamps first, then get advice/learn how to wire up a lamp to mains, and use relays to manage switching them on/off. Regards, Dana.
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    Simple lamps circuit

    You basically have to create a state machine, which you have in essence in words. Then either translate that into discrete logic or a processor. Question have you ever written any programs ? Regards, Dana.
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    Fixing an USB charger

    Can you [post a well focused pic of the board ? Regards, Dana.
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    Need a isolated adjustable device to raise signal voltage from .2~.8v --> ~.2~1.0v

    Tools to manage the OpAmp G calculations - https://www.ti.com/lit/an/sloa097/sloa097.pdf https://masteringelectronicsdesign.com/differential-amplifier-calculator-2/ https://www.ti.com/download/kbase/adc/DifGain.htm...
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    BAT60JFILM Vs BAT60A Vs BAT60B

    BAT60B vs A, 1/2 the Vf, B large Ir >> A leakage current difference. Regards, Dana.
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    Building a supply to regulate between 400A-100A

    One approach : https://electronics.stackexchange.com/questions/264698/100a-constant-current-supply-for-low-resistance-load This basic circuit could be adapted using .Kelvin sensing o.pf a shunt to regulate base drive of transistor array...
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    Why do they use a voltage divider in this instance?

    Or a two terminal constant current diode regulator (each leg) : https://www.diodes.com/assets/Datasheets/AL5809.pdf It has lower droput V, 2.5V, vs 3.0 of the 317. Regards, Dana.
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    Why do they use a voltage divider in this instance?

    A quick and easy way is (each leg) : Its short circuit protected, thermal protected, line ripple rejection, can get in SOT package or TO220 or TO92 package. Also very close leg matching current due to decent Vref accuracy and T stability. Note min load current to stay in regulation is 10...
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    Circuit selector

    One possibility to get rid of all the switching and severe MOSFET requirements : https://link.springer.com/chapter/10.1007/978-1-4614-0403-3_7 A compendium of articles on active resistors (see references at page bottom) : https://link.springer.com/article/10.1007/s10470-009-9351-5 One...
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    Series Current regulator ? Load and minimum load help

    LM317 there just for the min low current requirement, 100 mA, not the 6A. Thats why the other questions were asked to establish if the 6A when on is also to be a contact current, that will lead to a solution more like : Or for high efficiency ...
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    Series Current regulator ? Load and minimum load help

    A fixed 100 mA current from 28 V could be LM317 : The 6A, is that also a constant current or a varying load when PWM is in active for 34% ? What is the duty cycle accuracy, same for current if constant current when active ? Regards, Dana.
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    EPS GENERA 161 welding machine no output voltage, no 24 V reading on the relay's coil legs

    Do you have a schematic of the welder ? Regards, Dana.
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    Buying a Digital Oscilloscope.

    I bought 4 years ago a DS1074Z Rigol, and very happy with it. Including build quality, regular periodic updates of firmware and now no longer because firmware is up to date and complete. Very good FFT for this price range. The two channel model of this will meet your budget I think. I like its...
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    Project design with minimum cost

    WiFi relay modules (down to < $7 in an inflated market) - https://www.banggood.com/search/wifi-relay.html?from=nav Regards, Dana.
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    Kenwood TS 830S

    Your scope is capable of seeing 50 - 100 Mhz oscillation, eg. if its not neutralized ? Probe not stopping osc because of its C....so you never see it.....? Of course you would see rig current draw jump when you put it on CW... I have been looking for the W version of tube info, I read some...
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    Kenwood TS 830S

    You have seen this chart ? http://www.wb4hfn.com/KENWOOD/Manuals/TS-830S%20Alignment.pdf Regards, Dana.
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    Kenwood TS 830S

    Just a caution, it is for protecting the finals. Caps on the finals not come loose, I have had that happen. Screen supply correct. When you key down on rig you see no change in scope pics at grids, plate....? Coax cable to dummy load good ? I have had problems with cheap Chinese knockoffs...
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    Circuit clarification

    Yes, quite easy. https://www.edn.com/use-lt-spice-to-analyze-input-filters/ Regards, Dana.
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