Show A W 7 1 1 1 M ar chandl sins liffin kf S FIG I 1 FIG 2 1 WO 04 rd basket weave it right method of wound top left show shows form for edge tying this type coll lower left solenoid form for backet lit weave coll Col lols form for spider web coll lorenz wind ng rig right t ow log colls coils require large largo wire ire spacing be between tileen tuni tums and no support supporting inZ dielectric II 11 one UP a supporting tube or framework he must he sure it ti to high ity keeping metal out of the field of the coll coil in important the method of winding of it itself elf Is I 1 not essential to it lose lost construction but certain mp methle trull of wiring help in ninny war ays to ninke wake possible the requirements quire ments set forth ol 01 basket weave coll for instance carlly mean means pacing between turns and rather large wire the difference between the various 1 way ways of winding Is shown in the alg area of course every one know that a coil wound on a it tube or so that the completed coll coil itself forms a tube Is known as a a solenoid NIn winding ding it is I 1 probart proba fly the most common form of winding we find then there Is spir it in winding in which the diameter of it t e oils progressively increases one turn Is wound on top of the other outward so the resulting eull ull li is one turn wide it lt resembles ree emble somewhat tome what the flat pancake type the form tor for which Is at the right of fig 2 tills this type Is called the spider spiderweb web coll for obvious reasons the inner dl ameter or diameter of the first turn Is usually about an inch and a half there must be an odd number of alotis lot usually the winding vinding goes in one slot and ont out tho other under and over each spoke in turn there Is no rea son on why it hould not go under two and over I 1 two 0 just as in the I 1 arenz windings shown n in the other figures the rho usual itei nartz coll coil Is a spiderweb coll coil and cun can be very easily made by cutting a 0 6 to 8 inch disk of dl electric and blotting slotting it after the man ner shon a characteristics of colls coils basket weave weale coll coils are of two types edge wound resembling the spiral and spider web or solenoid wound lesem bling the coll on a tube the same forma forms may be used for basket weave as its for lorenz and are illustrated in figs I 1 and 2 in fit fig I 1 ta is shown the most coa con form you can have around the work table it Is a center disk with 13 cylindrical spoke spokes the made up form may bo be purchased complete it mity be made from a sa cawed off piece of curtain rod and 13 spokes the spokes must be removable however there must be an odd number of them and they can be any material as can the center thirteen Is 1 just a convenient lucky number in winding the edgewise basket weave the wire ire will go over one spoke and under the next nea over and under one spoke at a time the resulting coll will mill be a latticework effect sin aim liar her to the reed basket baskets so often seen or reed furril furniture ture in winding the lorenz coll go over two spokes and under two over and under two at a time continually because there Is an odd number you will continually shift the starting point for e each ac h turn tum as shown at the left of fig 1 1 while both first and second tuna tums tu na tart start by going over spoke A one goes over and one goes under spoke TL this Is because of the odd number of pokes spokes not divisible by two the rot r coll coil Is shown at the right of rig 1 with more of a trellis effect both sides are smooth while neither ide side of the basket weave Is smooth the basket weave eave however Is self holding but the lorenz coll roust must be tied with tiring string at the corners comers as in dilated dica ted before pulling out the spokes that Is the white cord one bees sees on the coll coils told sold commercially th the winding the spider web coll coil requires the winding form to remain in the coll COIL the lorenz type require requires tying cp up the basket weave Is t self ind and self holding bolding the spiderweb spider web om what lees less inductance than thin of the other others for the lame same number tuma th no others do not differ duter ma except in amount of wire and elic of coll for the same number lumber of 0 turn I 1 alioth the basket weave and tile lorenz winding may take on the th solenoid form by using the ending device shown in rig fig 2 here instead of 0 spokes of a wheel we have pine pins arranged in a birc circle ito and forming really a it latticework tube take IL board strike a 8 inch circle and drive la ili I 1 F pikes equally paced spaced or erect pins in the board there must be an odd number usually 15 are used but any odd number can be used and of course the smaller the diameter the lees less the number of pins in the solenoid type the roll coil will slip off the pin pins so 0 o the pins are not removable from the board necessarily ln the solenoid lenold eo winding as in the this edge winding lading the basket weave coll Is obtained by winding over and under one pin at a time tir lorenz wind ine ing la Is obtained as shown by the dotted line winding in and out over oyer and un der two pins at a time there Is no more real satisfaction in construction to be obtained than to wind a set of lorenz colls coils both of the solenoid and the edge type the fin ish and appearance alpe arance Is ls perfect with these home hom homemade made coils in both cases do not forget to tie up the corners before removing the coll coil from the form whether solenoid or edge in general for number of turns fol low the salue standard as the honey conia or as the so solenoid lenold but wind a few more turns than specified for either it Is a simple matter to un wind a turn or two and cut off the wire but adding a turn or two to mean means soldering on a piece of wire each time what you should know about drilling Pan panel elti the simplest things in radio are the ones that are apt to cause the most trouble lor instance drilling the panel this Is in an almost insurmountable obstacle to some of the builders who ho have never constructed a me jbv wb view the brace and bit as a tool of the master mechanic I 1 aret arst it Is necessary to lay out the I 1 position and size of the holes to be drilled where an instrument Is held in place with two or more setscrews sete crew it II 11 best to make a half inch hole for the center shaft it if the instrument Is then slightly off it will still turn tum easily on its bearings without binding in ili the cartons containing the inspru ments are often template templates showing the spacing of the h holes 0 I 1 esi to be drilled these should be used when he drilling the holes if made of paper they can be pasted directly on the panel and the holes drilled through them the paper Is then removed a wet cloth if it Is necessary nece esary to calculate your own petitions positions do so by measuring th the a distance that one side of the hole is from the shaft and then the distance below it IL for instance a rute rule Is to laid against the shaft and touching the let set screw the reading on the ruler with one half the diameter of the shaft or an in eighth of an inch will be the die dis tance to one bide side then by doing this straight up and down instead of id way ways the depth will be found now from the center holemark hole mark measures the proper distance to one side and the proper depth from there them mark and drill the location of the other hole or holes may be determined by revere 1 ing the procedure improve the tuner the materials and time required to construct a wave trap would remodel a poor tuner into a good coupled circuit hook book up the cost of a factory made wave trap would buy an all efficient tuning coil and condenser for the present set sel in either case the efficient eff ident coupled circuit tuner Is far ahead ag rf aray ny with is wit trap tra |