Working on strowger phone exchanges involves a lot of soldering, but unlike modern electronics, you can`t use a fancy temperature controlled soldering station, with built in solder stand etc when you`re up a ladder. For one thing, you`ve usually only got a 50V supply available and for another, there`s no where to put the base unit half way up a rack. So the irons we use aren`t temperature controlled, run off 50V,
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have electrically isolated tips (so you don`t accidentally earth things when you`re working on live circuits) and the soldering iron stands are connected to spring clamps so can easily be moved around the frame. The iron in the picture is showing its age somewhat (and having looked at the picture carefully, I notice there`s a split in the insulation that needs taking care of) but it does illustrate a tip I was recently given by a phone engineer. Always wrap a bit of solder around the cable of your iron, there`s nothing more frustrating than being up a ladder and realising your solder is in your toolbox or worse, on the bench at home. Having some emergency solder available within inches of the tip of your iron can save a lot of frustration. To celebrate that I`ve got enough tie lines working to phone from one side of the living room to the other, via the asterisk server at the Dean Forest Railway. I made a video of me dialling 30-0-50-91-491. Dialing 30 takes you out through an outgoing tie line and onto the junction selector, 0 takes you back into the 50/7A on an incoming tie line, 50 takes you out through another tieline and into my asterisk server. 91 are the access digits which take you in to the asterisk server at the Dean Forest Railway, 491 then takes you back into my asterisk server, which then dials 39 ³ on your behalf which takes you out *another* tie line into my 10/2A PAX and then it finally dials a 5 to ring...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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