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Point-to-point construction

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250: 258: 266: 122: 520: 25: 386:; the capacitance between a circuit-board trace and some other conductor, and the inductance of a short track, become significant or dominant at high frequencies. In some cases careful PCB layout on a substrate with good high-frequency properties (e.g., ceramic) is sufficient. An example of this design is illustrated in an application note describing an 219:, a similar method that is) and is carried out manually, making it both more expensive and more susceptible to wiring errors than PCBs, as connections are determined by the person doing assembly rather than by an etched circuit board. For production, rather than prototyping, errors can be minimised by carefully designed 498:
flipped upside-down with their pins sticking up into the air like a dead insect, the leads of components are usually soldered directly to other components where possible, with many small circuits having no added wires. While it is messy-looking, free-form construction can be used to make more compact
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If parasitic effects are significant, point-to-point and terminal strip wiring have variable parasitic components, while the inductance and capacitance due to a PCB are the same for all samples and can be compensated for reliably which may be essential for some RF circuits. In some heavily optimised
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and other large components were mounted to the top of the chassis. Their wires were led through holes to the underside or interior. The ends of lengths of wire or wire-ended components such as capacitors and resistors were pushed through the terminals, and usually looped and twisted. When all wires
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A stripboard is a board with holes in square grid pattern, commonly with a 0.1-inch pitch; all the holes in a straight line are connected by a copper strip as on a PCB. Components are pushed through from the side without strips and soldered in place. The strips can be interrupted by scraping out a
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equipment even after the introduction of printed circuit boards. The heat of the tubes can degrade the circuit boards and cause them to become brittle and break. Circuit board degradation is often seen on inexpensive tube radios produced in the 1960s, especially around the hot output and rectifier
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construction. Historically this could be literally a breadboard, a wooden board with components attached to it and joined up with wire. More recently the term is applied to a board of thin insulating material with holes at standard 0.1-inch pitch; components are pushed through the holes to anchor
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have reissued some of their older models, using this type of construction as a design feature, although their standard products have long used PCBs. Thermionic valve equipment usually does not have the valves mounted on the PCB in order to avoid heat damage, but instead use PCBs for the wiring,
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Particularly in complex equipment, wired circuits are often laid out as a "ladder" of side-by-side components, which need connecting to ladders or components by wire links. A good layout minimizes such links and wiring complexity, often approaching that of direct point-to-point. Amongst complex
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For high-frequency work, a grounded solderable metallic base such as the copper side of an unetched printed circuit board can be used as base and ground plane. Information on high-frequency breadboarding and illustrations of dead bug with ground plane construction are in a Linear Technologies
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them, and point-to-point wired on the other side of the board. A type of breadboard specifically for prototyping has this layout, but with strips of metal spring contacts beneath a grid of holes into which components are pushed to make electrical connections like any removable
448:. Some portion of the terminals in a straight line in one direction are electrically connected, commonly in groups of 5-10 with multiple groups per row, these may be interspersed with columns that span the height of the board for the more common connections (typically the 149:(vacuum tubes) were relatively large, relatively simple (the number of large, hot, expensive devices which needed replacing was minimised), and used large sockets, all of which made the PCB less obviously advantageous than with later complex 503:
and in RF circuits where component leads must be kept short. This form of construction is used by amateurs for one-off circuits, and also professionally for circuit development, particularly at high frequencies.
609:, describes and illustrates dead-bug breadboards with ground plane, and other prototyping techniques. Illustrated in Figures F1 to F24, from p.AN47-98. Information on breadboarding on pages AN47-26 to AN47-29. 390:-based generator of pulses with risetime of a fraction of a nanosecond; the (few) critical components are connected directly to each other and to the output connector with the shortest possible leads. 344:-intensive, subject to error and not suitable for automated production. Even after the introduction of printed circuit boards, it did not require laying out and manufacturing circuit boards. 363:
equipment, such as amplifiers, continues to be point-to-point wired using terminal pins, often in very small quantities. In this application modern point-to-point wiring is often used as a
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can be used in cases where a PCB would be too big or too much work to manufacture for a small number of components. Several methods of construction are used. At one extreme a
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reinforced with cotton. The insulator has an integral mounting bracket, sometimes electrically connected to one or more of the stamped loops to ground them to the chassis.
456:, fall somewhere between PCBs and point-to-point; they do not require design and manufacture of a PCB, and are as easily modified as a point-to-point setup. 277:(also called "tag boards"). A terminal strip has stamped tin-plated copper terminals, each with a hole through which wire ends could be pushed, fitted on an 234:
can be wired in a similar way the density means that component placement is usually fixed by a substrate that components are inserted into.
42: 566:, p.AN47-94, figure D3, head of avalanche pulse generator. "Lead lengths ... should be experimented with to get best output pulse purity." 89: 273:
Terminal strip construction, which is often referred to as point-to-point construction within the tube guitar amplifier community, uses
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to bridge as much of the distance between connections as possible, reducing the need to add additional wire between the components.
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A few large brand names still use terminal strip-type point-to-point boards, but usually for special product lines. Electric
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Sometimes true point-to-point wiring—without terminal strips—with very short connections, is still used at very high
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Underside of the chassis of a 1948 Motorola VT-71 7" television, showing the complexity of the point to point wiring.
108: 145:(PCBs) and automated assembly gradually became widespread following their introduction in the 1950s. Circuits using 231: 647: 161:. A common practice, especially in older point-to-point construction, is to use the leads of components such as 353: 46: 125:
Section of a typical Australian late 1930s radio, showing the point to point construction between components.
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An intermediate form of construction uses terminal strips (sometimes called "tag boards"), eyelet boards or
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can be used with a perforated board, producing neat and professional results. At the other extreme is "
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and follow an exact assembly sequence to ensure that they did not miss any components. This process is
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to hold wires to an insulating wooden or ceramic board. The resulting devices were prone to fail from
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to be connected had been fitted to the terminal, they were soldered together (and to the terminal).
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continued to use point-to-point wiring in its tube-based television sets until the early 1970s.
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section of the copper, stripboard cutters are available for this task which are effectively a
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strip, usually made of a cheap, heat-resistant material such as synthetic-resin bonded paper (
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Prototypes which are subject to modification are often not made on PCBs, using instead
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design feature rather than a result of the economics of very-small-scale production.
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point-to-point RF constructions the circuit can be tuned by bending wires around.
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Making an electronic circuit by directly connecting the leads of the components
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protects the circuit from its environment, and users from electrical hazards.
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Point-to-point and terminal strip construction continued to be used for some
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Point-to-point wiring is not suitable for automated assembly (though see
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Before point-to-point connection, electrical assemblies used screws or
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achieving the economy of mass-produced PCBs without the heat damage.
395: 375: 364: 325: 216: 193: 177: 166: 242:"Terminal strip" redirects here. For strips of screw terminals, see 180:
contacts, or mechanical loosening of the connections. Early premium
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with a handle, they are used by rotating on the holes in a strip.
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Professional electronics assemblers used to operate from books of
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stand out for their very well-designed point-to-point wiring.
212:. Solder makes a strong electrical and mechanical connection. 317: 309: 209: 192:, but this was expensive. The crucial invention was to apply 630:
shows an example of point-to-point construction applied to
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Point to point wiring on a homemade tube amplifier circuit.
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Linear Technology AN47 - High Speed Amplifier Techniques
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Illustration of interior of Tektronix 310A oscilloscope
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Point-to-point construction of military radio equipment
596:"Application Note 47: High Speed Amplifier Techniques" 153:. Point-to-point construction is still widespread in 515: 478: 499:circuits than other methods. This is often used in 49:. Unsourced material may be challenged and removed. 196:to electrical assembly. In soldering, an alloy of 590: 639: 237: 137:is a non-automated technique for constructing 623:A picture of a "dead bug" style circuit patch 320:to the underside or interior of the chassis. 109:Learn how and when to remove this message 264: 256: 248: 141:which was widely used before the use of 120: 244:Screw terminal § Multiway versions 640: 586: 584: 188:, sometimes used welded copper in the 47:adding citations to reliable sources 18: 581: 13: 14: 664: 616: 409:Placing the completed unit in an 518: 204:(and/or other metals), known as 23: 34:needs additional citations for 569: 557: 546: 452:rails). Such breadboards, and 1: 628:Progressive Wiring Techniques 539: 459: 428: 352:tubes. American manufacturer 58:"Point-to-point construction" 296:was constructed first, from 7: 511: 238:Terminal strip construction 135:point-to-point construction 10: 669: 463: 432: 241: 653:Electronics manufacturing 479:"Dead bug" construction 648:Electronics substrates 484:Free-form construction 270: 262: 254: 151:semiconductor circuits 143:printed circuit boards 126: 394:devices, the pre-PCB 268: 260: 252: 232:cordwood construction 159:electronic components 124: 388:avalanche transistor 221:operating procedures 43:improve this article 378:range) to minimise 526:Electronics portal 508:application note. 494:" style, with the 271: 263: 255: 184:, especially from 127: 592:Linear Technology 380:stray capacitance 372:radio frequencies 308:strips were then 155:power electronics 147:thermionic valves 119: 118: 111: 93: 660: 610: 608: 606: 605: 600: 588: 579: 573: 567: 561: 555: 550: 528: 523: 522: 418:guitar amplifier 190:bus-bar circuits 114: 107: 103: 100: 94: 92: 51: 27: 19: 668: 667: 663: 662: 661: 659: 658: 657: 638: 637: 619: 614: 613: 603: 601: 598: 594:(August 1991). 589: 582: 574: 570: 562: 558: 551: 547: 542: 524: 517: 514: 481: 468: 462: 437: 431: 275:terminal strips 247: 240: 115: 104: 98: 95: 52: 50: 40: 28: 17: 12: 11: 5: 666: 656: 655: 650: 636: 635: 625: 618: 617:External links 615: 612: 611: 580: 568: 556: 553:musicradar.com 544: 543: 541: 538: 537: 536: 530: 529: 513: 510: 480: 477: 464:Main article: 461: 458: 433:Main article: 430: 427: 239: 236: 117: 116: 31: 29: 22: 15: 9: 6: 4: 3: 2: 665: 654: 651: 649: 646: 645: 643: 633: 632:surface-mount 629: 626: 624: 621: 620: 597: 593: 587: 585: 577: 572: 565: 560: 554: 549: 545: 535: 532: 531: 527: 521: 516: 509: 505: 502: 501:BEAM robotics 497: 493: 489: 485: 476: 474: 467: 457: 455: 451: 447: 442: 436: 426: 423: 420:manufacturer 419: 414: 412: 407: 403: 401: 400:oscilloscopes 397: 391: 389: 385: 381: 377: 373: 368: 366: 362: 357: 355: 350: 345: 343: 339: 334: 331: 327: 323: 319: 315: 311: 307: 303: 299: 295: 290: 288: 284: 280: 276: 267: 259: 251: 245: 235: 233: 229: 228:turret boards 224: 222: 218: 213: 211: 207: 203: 199: 195: 191: 187: 183: 182:marine radios 179: 175: 170: 168: 164: 160: 156: 152: 148: 144: 140: 136: 132: 123: 113: 110: 102: 91: 88: 84: 81: 77: 74: 70: 67: 63: 60: â€“  59: 55: 54:Find sources: 48: 44: 38: 37: 32:This article 30: 26: 21: 20: 602:. Retrieved 571: 559: 548: 506: 491: 483: 482: 469: 450:power supply 438: 415: 408: 404: 398:vacuum-tube 392: 369: 358: 346: 335: 330:tube sockets 322:Transformers 304:. Insulated 291: 274: 272: 225: 214: 171: 134: 128: 105: 96: 86: 79: 72: 65: 53: 41:Please help 36:verification 33: 634:components. 454:stripboards 349:vacuum tube 338:photographs 298:sheet metal 131:electronics 642:Categories 604:2016-02-14 540:References 488:wiring pen 466:Stripboard 460:Stripboard 441:breadboard 435:Breadboard 429:Breadboard 384:inductance 361:audiophile 326:capacitors 279:insulating 167:capacitors 99:March 2010 69:newspapers 534:Wire wrap 473:drill bit 446:connector 411:enclosure 396:Tektronix 376:gigahertz 365:marketing 217:wire wrap 194:soldering 174:wire nuts 163:resistors 512:See also 492:dead bug 422:Marshall 374:(in the 324:, large 306:terminal 287:bakelite 178:corroded 139:circuits 318:screwed 310:riveted 294:chassis 186:Marconi 83:scholar 354:Zenith 314:nailed 285:), or 206:solder 85:  78:  71:  64:  56:  599:(pdf) 359:Some 342:labor 210:steel 90:JSTOR 76:books 382:and 302:wood 292:The 283:FR-2 202:lead 200:and 165:and 62:news 496:ICs 316:or 300:or 198:tin 129:In 45:by 644:: 583:^ 328:, 312:, 223:. 133:, 607:. 246:. 112:) 106:( 101:) 97:( 87:· 80:· 73:· 66:· 39:.

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electronics
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