Donor challenge: Your generous donation will be matched 2-to-1 right now. Your $5 becomes $15! Dear Internet Archive Supporter,. I ask only. Making a Transistor Radio [G.C. Dobbs, B.H. Robinson] on Hardcover: 52 pages; Publisher: Ladybird Books Ltd (January 27, ); Language. Making a Transistor Radio – Ladybird Book. Making a Transistor Radio Book Cover. Making a transistor radio is a book written by G.C. Dobbs, with illustrations .
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Leave a Reply Cancel reply Enter your comment here In areas of good signal strength, it will be possible to use the radio without an aerial at all. If nothing is heard, keep moving the position of the wi rc on the coke until a signal is heard. Using an OC71 here ensures that this shouldn’t happen as there is some inherent emitter resistance and lower gain anyway.
The value of capacity is written in microfarads, pF or sometimes MFD. Later I got the Radio Shack in-1 electronics lab, and with the radio in that kit I was able to pick up the stations in Sacramento.
Unfortunately the loudspeaker cannot directly replace the earpiece because its resistance is much lower than that of the earpiece, so it has to be matched into the circuit with a transformer. Take a small piece of wood, about l inch thick, and a piece of washed coke about the size of a pea.
For a more detailed explanation of this, you might like to read pages of the Ladybird book: You can tell which end is really anode or cathode by looking carefully to see which end the point contact wire is attached to, and which has the germanium crystal on a little mount. You will also have shared the thrill of thousands of other radio construc- tors, listening to sounds coming from a radio receiver which is your ow n work.
This encouraged me to buy “Learnabout Do you still have your radio? Construction was on Veroboard and you had to wind your own ferrite rod aerial here as well.
They fit neatly between position 5 and the previously unused position 6.
Unlike our crystal set, many modern transistor radios are sufficiently sensitive to pick up enough signal from the ferrite ladjbird of the tuning coil.
Set the tuning capacitor about midway and screw in the trimmer unlit the radio begins to howl.
MAKING A TRANSISTOR RADIO – LADYBIRD BOOK
IGuF tS volts, working efecirolytsc capacitor. Ladybird Radio Kit Of Parts. That stabilises the d. The air spaced capacitor supplied will need some different mounting scheme but they have a decent length of shaft and they are easier to tune with, requiring less turning force. I miss woolworths, Ladyvird remember dying just a little when they all closed down. The sclderrng iron bit and metaJ shaft can burn the skin!
If tftrs is so, remake the joint. I probably still have a copy of it somewhere. Transistors are designed so that a small, changing current between the base and emitter produces a large current change between the collector and the emitter. It consists of two plates which arc separated by insulating material; the circuit symbol shows this. Finally, the reader is shown a regenerative front end for their makiny that replaces the crystal set.
Woolworths produced a series of these, I found a mention of them here: The centre transitor is joined to a movable contact which slides over the track when the shaft is rotated. Look at most pieces of equipment and you will see several small, wire-ended tubes with brightly coloured bands.
Sorry Ladybird books, but transistor beta dependent design is bad design. Softwood is used for the base. It should be possible to hear some local stations by adjusting the tuning capacitor. Interestingly, there is a spare screwcup position just where these parts are required. This makes spiral transisfor which can then be pulled out to reach the screws. The connecting wire used should be PVC covered copper wire, the ends being bared before they are trapped under lhe screwcups.
This radio is designed for the beginner, so a non-soldering method of connection is used. The method is explained in the diagram opposite, but remember the following tips: I remembered that back in the day screws were sometimes used as connection points, so I connected my circuit using wood screws with rounded heads and flat underside on plywood board.
For the aerial to be effective, the other side of the tuned circuit has to he connected to earth.
Wore a tie to private school, it was part of the uniform, but not at home. The battery is the small transistor radio type PP3, for which can be obtained an inexpensive snap connector. I have the full set of them, but they are the newer reprints.
A circuit diagram is like a map. When radio waves carrying an audio frequency arrive at a receiver, three things happen: By using our website and services, you expressly agree to the placement of our performance, functionality and advertising cookies.
YELL nr 47k mm Biasing the transistor The transistor amplifier we have built is the simplest arrangement possible. Some soft pine is what you want, and offcuts from the local DIY store are about 50pee.
The Ladybird Radio
For those who wish to solder the connections, the technique is explained on the ladygird back covers of this book, A simple method of connecting the components uses wood screws and washers. Well you can see the pictures of the one I’ve made and the similarity to the illustrations in the book.
Possibly translated from these UK books presented here.