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5

Let me make a life a little easier with a simplification of your hard to read circuit: - The simplification is getting rid of 50% of the changeover switches. What can you use for these switches? I would consider using N-channel MOSFETs; two per switch element. You will need a supervisory circuit that of course needs to be very lower power but I don't see ...


5

Use a dual-pole switch. DPDT or DPST. That’s two separate switches that share mechanics. The same naming convention also applies to relays.


5

I have worked with a USB switch, and it's not as simple as it first seems. My first job at a new company was to debug why some of their USB switches were failing. The switch involved a 4 pole changeover, as you're describing. The symptom was that the PC froze about one in 10 switch events, on some of the switches. The switches appeared electrically identical,...


4

You will need a memory element such as a relay to hold the current direction of the motor. simulate this circuit – Schematic created using CircuitLab Here a DPDT relay and two microswitches are used. The motor M1 drives to the "left" when the top terminal is positive and to the right when the top terminal is negative. Suppose the relay is dropped ...


4

The Joule Thief mentioned in another answer is an excellent way to harvest the dregs of battery power. However, if surface mount components are not a problem, one can do slightly better. Look for ultra low power energy harvesting boost converters from Linear Technologies, Texas Instruments and perhaps other manufacturers. For instance, the TI BQ25504 can ...


4

Use the SPST switch to control a small DPDT relay.


3

Ratings like that are usually per contact. However, that doesn't mean you can combine two 20 A contacts in parallel to get a 40 A switch. You can not count on mechanical contacts to share current equally. You especially can't count on them to open and close, including all the bounces, at the same time. Imagine what happens when two switches in parallel ...


3

The AZ850P2-5 is a two-coil bistable relay. You apply a pulse between pin 1 and 5 to "set" the contacts, and between pin 10 and 6 to "reset" the contacts (5 volts, pin 1 and 10 positive). The contacts will stay in the last driven position - there is no need to apply power to hold the contacts in position. When the relay is "reset" there are connections ...


3

Any impedance "bumps" in the circuit will have "some" affect on achievable data rate, but as long as a switch is a sensible one and the connections are competent and the pairs are kept as undisturbed as possible, I'd expect no significant impact. Keep twisted pairs twisted for as much of their length as is sensibly possible - no need to overdo it. ie Avoid ...


3

As Ignacio points out 'the joule thief' is well known for sucking the final remnants of power from otherwise dead cells.


3

simulate this circuit – Schematic created using CircuitLab Figure 1. OP's circuit redraw with positive voltages on top and negative on bottom. simulate this circuit Figure 2. Using snubber diodes. In this configuration the maximum voltage that can appear across the contacts is 12 V + 2 x 0.7 V = 13.4 V. simulate this circuit Figure 3. Back to back ...


3

simulate this circuit – Schematic created using CircuitLab Figure 1. The complete kit. You can add a schematic into your question using the CircuitLab button on the editor toolbar. Double-click a component to edit its properties. 'R' = rotate, 'H' = horizontal flip. 'V' = vertical flip. Note that when you use the CircuitLab button on the editor ...


3

simulate this circuit – Schematic created using CircuitLab Figure 1. Implementation using a 4-pole 2-way switch. Figure 2. The 12-way rotary switches such as those made by Lorlin are available in 2-pole, 3-pole, 4-pole and 6-pole versions. A tabbed washer under the lock-nut limits the number of switch positions as required.


3

You need 4PDT switch, because MIDI is a balanced current loop. So two pins must be switched from each connector, and you have two connectors.


3

The diagram shows contacts in their normal state, and the slanting line shows the common contact. So you should be able to see that the pinout is: Coil NO1 COM1 NC1 NC2 COM2 NO2 Coil You can't be sure which set of contacts is no. 1 and which is no. 2 but it doesn't matter as they're interchangeable.


3

Here's one way to do it using an ON-OFF-ON switch like this one: one half of the switch in either on position shunts D3 preventing it from illuminating, this wastes about 20mA in the off position the LED lights the other half selects between the other two LEDs when on simulate this circuit – Schematic created using CircuitLab


2

What you're looking for is an analog switch. The control lines are selected via digital IO but the signals passing through are analog.


2

I know this post is 6 year old but, I hope this helps you in some way or at very least helps others who see it and need it? The circuit is actually very simple but hard to explain. Using a 3PDT (Triple Pole Double Throw) relay, Wire the first two poles as if it were a DPDT reversing relay. Connect Positive Power to the relay coil. The negative of the coil ...


2

Setup so each side can reverse the direction. DPDT switches on each side. simulate this circuit – Schematic created using CircuitLab


2

An alternating (push-on, push-off) pushbutton switch would be the easiest. It needs to be SPDT (or better). There are plenty available. simulate this circuit – Schematic created using CircuitLab If you want to connect it to an MCU or other logic, then R2 can be used to assure a valid '0' logic level, otherwise you don't need R2.


2

I think you want a two pole three (or four) position (2P3T) switch, although your "drawings" are confusing, and appear, to me, to disagree with your description. Perhaps MRX204A, as shown on http://www.nkkswitches.com/pdf/MRpowerLevel.pdf (Digikey MRX204-A - NKK Switches 360-2378-ND) would suit?


2

simulate this circuit – Schematic created using CircuitLab


2

There is no guarantee it will be the center terminal that is common. Just probe it out. It will almost surely be symmetric on either side, but it may be one of the end terminals that is the common for each side. In any case, there are only two 'states' for the switch, so write down what is connected to what when the plunger is pressed and what is connected ...


2

You might want to use a transfer switch. A transfer switch has 4 ports, which I'll call P1, P2, P3, and P4. In one state, P1 connects to P2 and P3 connects to P4. In the other state, P1 connects to P3 and P2 connects to P4. In your situation, you'd connect source 1 to P1, source 2 to P4, antenna 1 to P2, and antenna 2 to P3. Then your two states would be ...


2

Well.. here is the point.... Each contact is rated at 20A, however that does NOT mean you should tie them in parallel to get 40A. Here is the reasoning. Most of the AMPERAGE value of a switch has to do with life of the switch due to arcing at the contacts as the switch makes or breaks circuit. However, unless it's your day to win the lottery, no dual ...


2

I'm guessing that during a transition of your DPDT relay, an arc (that you stated seeing) may have bridged between the two "live" contacts (1 from AC Mains, one from Inverter), causing a momentary short between the AC Mains line, and the Inverter output. If this happened while the Mains and Inverter frequencies were offset by 90-270 degrees, there's a very ...


2

What are the different types of relays ? The three most common types of relay are Form A corresponding to a SPST normally open switch. Form B corresponding to SPST normally closed. Form C corresponding to SPDT. Do relays and switches always correspond to each other ? There are other types of relays than the three I mentioned above, but if you want to ...


2

"Normal Motor current" has no meaning, unless the Rated current and Start currents are both given. I would expect more than "No Load " current but how much load is irrelevant when direction reverse relay is activated, while running at full speed. This is because the Motor acts as a generator of Back EMF to reduce the no load current to just losses at some ...


2

Yes. Put the LED in parallel with your amp: simulate this circuit – Schematic created using CircuitLab


2

simulate this circuit – Schematic created using CircuitLab Figure 1. An example of using a DPST switch to control two circuits simultaneously while maintaining isolation.


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