That depends on how opto isolaters are used.
The same goes for any power supply , depends on the design and just what it is you are trying to achieve.
Be more specific and supply drawings of the required circuits involved.
Block diagrams will be fine for starters.
Otherwise you are quoting...
Not quite certain just what it is you are actually testing, the mains supply or the appliances/tools connected into the mains supply.
However, in Aus, if you have the appropriate self test certificate, which some builders/carpenters etc. do, then they test and tag their own tools and leads...
On a good day, correct voltages applied, with no rain, sun at 12 o'clock, no atmospheric noise or interference, no trees, open landscape, money in the bank, etc. etc....in other words.......... no.
Use LoRa modules.
Efficiency doesn't come into it (well, not so far as power out versus power in)....it's the required turns of the correct size wire to create the correct magnetic flux to pull in a solenoid of a given size and load, all the design being for DC operation.
This includes the armature design and the...
In addition, centre of co-ax (whatever it was supposed to do) connected to ground does nothing.
If Op wants something with range ability, look at using LoRa modules.
Yes....show the code (in code brackets....three dots in reply menu, more options (<>)....) that you are referring to.......
Most here are good, but not so good as to suggest changes or problems with code they cannot see.
Seems you have trouble reading the Queen's English so.......... as written in the instructions on the site I linked to.........
input voltage range: 2.2V-5V
If you want to wind your own coils and make your own dc solenoids, some study on how to design the complewte unit would be your first stop over.
Just winding a coil will not cut it, there is a lot more to it than that.
Usually best and cheapest all around is simply buy off the shelf what you...
Look for switching using "high side " P type mosfets.
You will require logic level mosfets as well.
One place of many to start..... https://www.digikey.com/en/maker/blogs/introduction-to-high-side-load-switches
Plenty of introductory tutorials on the internet on "how to use oscilloscope" and it looks like a good time for you to get started and do some study on how things work.
More than likely some good reading material out there as well.
Best place to start........
Sure is.
Very doubtful. say (99.9% against)
You will more than likely find the one you show is not long range.
Just adding an antenna doesn't make it a "long range " type.
It might increase the range slightly but a long range ype has an added amp on the board and usually a different...