Jun 14, 2017 i am trying to simulate an 50yearold circuit that i am guessing used germanium transistors. Return with us now to the halcyon days of germanium germanium transistor projects intrigued experimenters from the early days in the 1950s until the early 1970s. These were made by etching depressions into an ntype germanium base from both sides with jets of indiumiii sulfate until it was a few tenthousandths of an inch thick. Substitution of old germanium transistors in radio circuits. Im working on a guitar pedal that calls for a ac germanium pnp transistor and i was wondering why i might not want to just get a modern equivalent. The germanium transistor was more common in the 1950s and 1960s, and while it exhibits a lower cut off voltage, typically around 0. Pnp germanium transistors switches tools connectors and plugs antennas, antenna parts vacuum tubes, nixie tubes instruments, meters, gauges fuses, circuit breakers wire and cable fans, coolers, heatsinks. The vast majority of all diodes are the pn diodes found in cmos integrated circuits, which include 2 diodes per pin and many other internal diodes. Despite having been replaced by their silicon counterpart in most areas of electronics, vintage germanium bjts gbjts have. This is the fee to have germanium transistors tested for gain and leakage.
The circuit diagrams included in this manual are included for illustration of. Germanium and silicon metal for use in transistor manufacture must be so purified. A discrete 3w audio power amplifier circuit is shown in figure 1 employs a complementary output stage featuring the ac 187ac188 t 3 and t 4 germanium output transistor pairs. Hence comparing the schematic symbol to the pn junction in figure 4, we see the anode is the ptype semiconductor and the cathode is the ntype semiconductor. After this early germanium years, the production switched to the modern, temperature independent, and more stable silicon transistors like the bc108c, bc109c, and bc209c.
If you were willing to order enough parts, semiconductor manufacturers would make them any way you wanted them. Free transistor circuits books download ebooks online textbooks. Experiment 6 transistors as amplifiers and switches. Bfu768f npn wideband silicon germanium rf transistor. Since an integrated circuit is constructed primarily from dozens to even millions of transistors formed from a single, thin silicon crystal, it. The way a transistor works can be described with reference to fig. Message 6 datashret pnp transistor help posted by vilaemail in transidtor just wondering dagasheet you all go about buying germanium transistors in bulk. Crystal radio with one transistor audio amplifier, basebias. Does anyone have spice models for germanium transistors. The first germanium transistors that i encountered as a kid were the glassencapsulated ocxx types oc44, oc45, oc71, oc81d, oc81, etc. The electricity conducting material such as silicon and germanium has the ability to carry electricity between conductors and insulator which was enclosed by plastic wires.
That list includes carbonnanotube transistors, vertically oriented switches, 3d circuits, channels made from a mix of germanium and tin, and transistors that operate by a process called quantum. In this technique, p then n type dopants or n and p are successively introduced into an appropriately doped melt of germanium as a crystal is drawn from it in such a way as to produce three. The simulation works with 2n3904s but i want to get a better feel for how it might have worked with older parts. The first highfrequency transistor was the surfacebarrier germanium transistor developed by philco in 1953, capable of operating up to 60 mhz. A silicon transistor may be used if the basebias resistor is changed according to the table. Free transistor circuits books download ebooks online. Pnp germanium transistors prefer to be used in a positive ground circuit, just like the original rangemaster, the fuzz face, the tonebender, and many of the other very early pedals that used ge transistors.
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The configuration shown above is called an npn transistor. In the seventies, the superior silicon devices began to take. Ac datasheet pdf germanium small signal transistors gpd optoelectronic devices at the current specified in the datasheets. This amplifier can deliver a maximum of 3w into an 8. I n an attempt to show the evolution of the transistor based big muff pi circuit, and a reference for repairs, this article examines some key schematics for the different vintage electroharmonix variants, in chronological order, or as near as i can determine.
Ac datasheet, ac pdf, ac data sheet, datasheet, data sheet, pdf, gpd. A bar of germanium is grown from a bath molten germanium so doped that the material will change from p type to n depending on the temperature and rate of pulling. Has new, new old stock, and obsolete transistors in stock, including hard to find germanium transistors used in restorations, projects, and effects pedals. The transistor enables many circuits to be designed with a variety of different functions. Reliability data on a germanium pnp alloy transistor 322. The next type of transistor was based on shockleys comprehensive theory of junction transistors and was known as a grownjunction transistor. For more crystal radio circuits, simple one transistor radios, and more advanced low transistor count radios. Make offer transitron 2n332 to5 npn bipolar germanium transistor new lot quantity5 solid state 2n1701 germanium transistor npn 40v 2. The best feature about the germanium treble boost module is that it utilized the crown jewels internal negative 9 volt power supply. The latter types listed were often further encapulated in an aluminium can for improved heat dissipation the oc81d was often used as a driver ahead of an interstage phasesplitting transformer, and a. The operation of the transistor has been described in terms of the common emitter configuration. Whatever the circuit, the basic biasing conditions follow the same basic rules, but the topology of the circuit enables transistor to be used. Hi, i would ask that the germanium transistor section be changed from.
Here is the simple fire alarm circuit which costs less than 100 rupees. The 125 single transistor circuits shown in this book are examples of this usefulness. Substitution of old germanium transistors in radio circuits its also worth remembering that when that kind of circuit was popular, it was rare to find ge transistors with an ft of more than a few mhz, some were less than 1mhz. We also have new old stock ecg and rca sk transistors in stock and ready for delivery. Higher ip3, higher gain or lower noise figure possible with different application circuits 1. This means you can use any npn transistor, such as 2n2222, bc108, 2n3704, bc337 and hundreds of others. In 1959 they announced a number of these, including the oc41 and oc42 in the so2 metal can, and the rather unusual oc9 to oc141 which are germanium npn types in the so2 glass package, usually marked made in holland. All newmarket transistor circuits datasbeet chip transistors, diodestransistor packages. Transistor basics emitter to base junction is forward biased normally collector to base junction is reverse biased normally transistors are current operated devices, so kcl should be applied first.
Snap the small tabs on the top of the pots off with a pair of needle nose pliers 1 a500k audio volume pot 1 b1k linear fuzz pot hardware. You can always remember that the arrow points at the n material. Simple fire alarm circuit using thermistor, germanium. Germanium treble booster module build your own clone. Picking transistors for ff clones some transistors that have the right gain and low leakage can still be very hissy. The development of the germanium transistor in 1948 opened the door to countless applications of solid state electronics.
The xb8 transistor could be a custom part that had particular gain and collector to base capacitance characteristics. The gain of the germanium transistors is rarely higher than 120, and often between 30 and 90 in russian models, while that of silicon transistors is generally between 150 and 500. The column marked case is the outline of the transistor case. Although i do not play guitar, there is a forum called diyaudio, maybe they have some germanium transistor spice models for this particular type of fuzz simulation. The rate grown transistor is produced by an entirely different technique. Return with us now to the halcyon days of germanium. Semiconductor transistor, diode, ic cross reference.
If so, you either have to find another xb8 transistor somewhere or reengineer the circuit to work with something else. Germanium transistors the following table lists the parameters for germanium transistors. Experiment 6 transistors as amplifiers and switches our final topic of the term is an introduction to the transistor as a discrete circuit element. Sep 27, 2019 ac128 transistor datasheet pdf ac datasheet pdf download germanium small signal transistors, ac data sheet. In the seventies, the superior silicon devices began to take over the hobby market. Ge transistor manual 3rd edition american radio history. With no signal, the r4 value should be equivalent to two junction drops. Transistor uses, transistor rules, common emitter circuit, small signal amplification, fieldeffect transistors, jfet operating regions. The circuit diagrams included in this manual are included for illustration of typical. Pure germanium is a semiconductor with an appearance similar to elemental silicon. From 1950 through the early 1970s, this area provided an increasing market for germanium, but then highpurity silicon began replacing germanium in transistors, diodes, and rectifiers. Diode schematic symbol and actual picture of a common 1n914 diode the black stripe in the picture is the cathode. The first ffs manufactured in the uk used the ac128, a 45165 hfe european germanium pnp transistor, cheapcommon at that time later on replaced by the newmarket nkt275. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature.
If the transistor is a pnp, then the arrow points to the base of the transistor, otherwise it points to the output. Some circuits use tun for transistor universal npn and this is the same as our reasoning the transistor type is just to let you know. Collector leakage currentsilicon diode in series with emitter. Switching diodes switching diodes, sometimes also called small signal diodes, are single diodes in. This circuit is very easy to construct, cost effective and implementable. In this circuit germanium diode play very important role in detecting the fire. Germanium circuits are often overly sensitive to hfebeta by modern standards.
Motorola 2n59 pnp germanium power transistor motorola new old stock to3 case, gold leads vcbo. The case drawings are shown at the bottom of the page. The complete bom and the drilled enclosure is included, you only need soldering iron and basic tools. Ic cross reference cross reference ci stk cross reference ci tda cross reference ci sharp cross reference hitachi audio ic cross reference and circuit applications smd cross reference and equivalent we make every effort to ensure that the material on this site is accurate, however we do not warrant or represent that the information is free. Cases gec mazda stc aei hivac newmarket texas transistors. Comparison of germanium bipolar junction transistor models. The humble transistor q1 emitter e collector c base b transistor basics emitter to base junction is forward biased normally collector to base junction is reverse biased normally transistors are current operated devices, so. This module is devoted to the design of a transistor amplifier and this involves choosing the values of five resistors and three capacitors. Tin whiskers growing inside 45 year old af114 transistors. Germanium transistor projects intrigued experimenters from the early days in the 1950s until the early 1970s. Ge transistor manual 5th edition american radio history. From amplifiers to buffers and filters to oscillators, current sources, long tailed pairs and many, many, more. Therefore, in a semiconductor material such as silicon or germanium, we have a material which is a.
Texas instruments transistor and diode databook 1st ed 1973 datasheets for diodes from 1n251 on and transistors from 2n117 on acrobat 7 pdf 34. Comparison of germanium bipolar junction transistor models for realtime circuit simulation ben holmes sonic arts research centre, school of electronics, electrical engineering and computer science belfast, u. Npn and pnp small signal germanium junction transistors and. Antique radio forums view topic germanium transistors. The symbol of the transistor has an arrow on the emitter.
Emitter, collector and base in its essence, a transistor consists of two diodes arranged back to back. I need the specs on them so i can maybe find matching replacements. If you are going to mess around with germanium, build a test fixture like this one. Build germanium transistor projects with silicon transistors.
In circuits featuring fewer bjts, the largesignal ebersmoll model has been used 2. The circuit schematic symbol of a diode is shown in figure 5. Germanium transistors have a moderate gain, like tubes. Only a few inexpensive transistor types are used here. Spare electronic parts has new, new old stock, and obsolete transistors, fets, jfets in stock, including hard to find germanium transistors used in restorations, projects, and effects pedals. May 02, 2020 all newmarket transistor circuits datasbeet chip transistors, diodestransistor packages. Block diagram of fire alarm circuit using germanium diode. The web version of this book is available as a pdf at this url. This component model has been used in circuit models of complete guitar pedals, including wahwah 3 and phaser effects 4.
Germanium will sound a tad different than silicon in a given circuit, but its also worth pointing out that a great many excellent sounding pedals uses silicon components. Its funny actually, the exact limitations that caused germanium transistors to fall from favor in large scale electronics manufacturing, are the same attributes that. Redesign germanium transistor circuits, part 1 today. Semiconducting materials are treated by some chemical procedure called doping of. Radio circuits practical analog semiconductor circuits. A voltage or current applied to one pair of the transistors terminals controls the current through another pair of terminals. Electrosmash you can build the perfect germanium fuzz face. Germanium is a chemical element with the symbol ge and atomic number 32. Circuit diagram of 3w audio amplifier using ac187ac188 pair. Since an integrated circuit is constructed primarily from dozens to even millions of transistors formed from a single, thin silicon crystal, it might be interesting and instructive to. For more crystal radio circuits, simple one transistor radios, and more advanced low transistor. Transistor manual third edition general electric company semiconductor products 1224 west genesee street syracuse, new york.
Thanks to germaniums small bandgap, a transistor with a germanium channel could require as little as a quarter of the energy that a siliconchanneled transistor needs to switch to a conducting. It is composed of semiconductor material usually with at least three terminals for connection to an external circuit. The terminal on the left is called the emitter, the terminal on the right is. Stenning supplied four 4 af114 germanium transistors from his personal inventory for nasa component failure analysis group to determine composition of metal whiskers if any growing internally. The graphs of the above voltages and currents characterize a particular transistor e.
Prototype of a 10w amp, all russian germanium transistors. It is a lustrous, hardbrittle, grayishwhite metalloid in the carbon group, chemically similar to its group neighbours silicon and tin. I am trying to find data on pnp germanium xb8 and xb9 transistors. Unijunction transistor circuits 56 theory operation. Great deals on nos, surplus, obsolete and hard to find electronic parts and components for hobbyists, musicians, audiophiles, amateur radio, swl, restorations, and technicians. One of the many virtues of the transistor is its ability to function singlehandedly in all kinds of circuits. Cross reference electronic circuits, tv schematics, audio. Base input characteristics voltage comparator circuit. The operation of the transistor is very dependent on the degree of doping of the various parts of the semiconductor crystal.
Transistor consists of three layers of semiconductor, which have an ability to hold current. As the bom and all the documents are available you can get the parts and diy you can also order nos ussr germanium transistors. Of course, mullard also produced switching transistors for use in computers and logic circuits. A schottky diode may be substituted for the germanium diode. Additionally, germanium transistors usually didnt have as much gain as was neededwanted, leading to circuit design decisions that would be considered really bad today. Comparison of germanium bipolar junction transistor.
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