Casette Tape Recorder

After testing a dozen different makes of cassette tape recorders we found that the ValiaSt was by far the easiest to use- The fidelity is good and the push button system outstanding. Has battery levei meter, recordfnq level meter, jack for feeding hi-fi or tv, operates from switch on mike. Great for recording DX contacts, friends, at the movies, parties, unusual accents and things like that. Once you try it you will be usinq it like a camera. Check this price anywhere, It is a lulu!

SPECIAL, ONLY $44.50 ppd 24 HOUR CALENDAR CLOCK

This clock reads out the day, date and time in large, easy to read numbers. None of that tittle tiny number business for your shack. Set this up on GMT and never make a mistake again on log-qinq time and date. 8l,x3l/2,lx3,/2". brushed aluminum case. Synchronous self-startinq movement, I 10 v 60 cycles. Make your operating desk look outstanding with this new type of clock..

SPECIAL $49.50 pp TRAVEL-CLOCK RADIO

Eight transistor clock radio, complete with clockF radio alarm, and slumber setting! Weighs less than IV2 pounds. Great gift for a traveling friend or relative. Or yourself. Earphone for private listening, if you like. Batteries Included.

SPECIAL ONLY $17.95 pp AM-FM DIGITAL CLOCK RADIO

Here Is somethinq entirely new In clock radiosa digital ctock plus a very sensitive AM-FM with AFC radio. This is the first digital clock radio ever Imported into the U.S. The radio Is all solid stater of course- This makes a wonderful radio for the bedroom. Price clock AM-FM radios, even In the bargain fliers, and notice the amazinq low price for this one.

SPECIAL ONLY $49.50 pp DESK NAME PLATE

Your name and call on a beautiful desk plate might normally cost you around $10. These plates are walnut qrained and are available with up to 20 letters and spaces. You can have your full name or your first name and call. Immediate delivery on all orders. 10" lonq by about I" high;" Identify your station With one of these plates.

SPECIAL $2 pp

REDLINE, Jaffrey, N.H, 03452

Please send postpaid the following; check enclosed.

□ tape recorder

□ travel clock radio

Address

C-ffi-L

A, E, McGee, Jr. K$LLI 2815 Mater horn Dr. Dallas, Texas 75228

When building any complex piece of electronic equipmentj you will usually find that the majority of the wiring consists of power and control wiring of one kind or another! his wiring is usually completely uncritical as to length and placement, so ordinarily not much thought is given to its installation. Any method of wiring may work well electrically, but later on, when it is necessary to trouble-shoot the circuit and make repairs, you may find that you have built-in some unnecessary troubles.

If you wire directly from point to point, always using the shortest possible wire, the wires will cross each other at many odd angles and will very likely pass over other components, fhis makes access to these components difficult. Also it is hard to find a clear path for the signal wiring when power leads are everywhere.

A much better plan is to run the nonsignal wiring around the sides of the chassis, bound together into a neat bundle, with leads breaking-out at right angles near each component. A wiring harness like this is most easily made outside of the chassis, A

little time should be spent in preparing a wire chart and a full-size layout ol the chassis, This will speed the construction of the cable and make errors unlikely; also, you will have a complete record of where each wire goes in the circuit.

The wire chart and chassis layout

To make a wire chart, rule oii five vertical columns on a sheet of paper, and mark them with these headings: Wire No., Size, Color, From, and To. Under Wire No., number the wires consecutively; under Size, put the gauge of the wire; under Color, use the standard color code (a red wire would be 2, a white-blue-green wire 965, etc.); under From and To, put a description of the components or terminals to which line wire is to be connected.

Now draw a full-size layout of the chassis. This need onlv be a simple outline of the chassis, with the approximate location of all the major parts drawn in. Decide where you want the main body of the cable and the breakouts to the components to run, and sketch them in. Use this layout, together with the schematic, in making the wire chart Start from one side of the circuit diagram and begin filling in the wire chart, marking through each wire with a colored pencil as it is put down on the wire chart. For example, say you start with a white, 18-gauge wire from the power switch to the primary of the power transformer. You would put down something like this; Wire No. - 1, Size - 18, Color - 9, From - SI, To - Tl, terminal #L Then mark the schematic to show which part of the wiring is now on the wire chart, A fairly large-size copy of the circuit diagram is helpful.

The chassis layout is useful when several components are connected to the same wire. The order in which the components appear on the schematic may be considerably different from their relative locations on the chassis. Reference to the chassis layout when making the wire chart will prevent excess wiring in the cable, caused by the same wire doubling back on itself to get to a previous! y-skipped component.

Use wires of as many different colors as possible. Assortments of small quantities of wires in various colors and sizes are available at bargain prices from most of the large mail-order parts distributors. You can use the colors according to some code of your own making, or just use them consecutively, and when you run out of colors start over again.

Making the harness

To make the harness, first tape the full-size chassis layout to a piece of wood. Drive some small nails along each side of the sketchcd-in cable. Place the nails in pairs

The clove hitch.

An extra tuck ts added to the clove hitch to prevent its loosening.

and space them about one-half inch or so, depending on the number of wires in the cable. Kefer to the wire chart and begin to lay the wires in place, Put a check mark beside the wire number on the chart as each wire is put in. Be sure to leave sufficient length at the ends of the wire to allow making the connections. The wires may be stripped and tinned at this time, but a rieater job will result if you leave this until after the cable is put into the chassis.

Lacing

When all the wires are in place, you can start binding them together. There are a number of different types of wraps, ties, and bindings that can be purchased, but in my opinion the neatest and simplest method for a small project is to tie the cable together with cord. Special lacing cord is avail able, and the flat nylon braid type will do a very attractive job. Any type of heavy twine will do about as well however . It should be large enough in diameter that it won't cut into the insulation.

The wires may be laced together, or simply tied at intervals, I prefer to tie them, as it is more secure and takes little more time than lacing, Lacing is recommended, however, when long runs of cable are made up. Tie the cable every few inches along the main body, and place a tie on both sides of each breakout.

A good knot for fastening the wires is a modified clove hitch, or ordinary clove hitch with a square knot tied over it to lock it. If maximum security is desired, put a drop of glue on each knot. For the nicest-looking job, the knots should be under the cable,

where they will be out of sight. The easiest way to do this is to lirst make enough temporary ties to hold the harness together, Then carefully remove it from the jig and turn it over. Finish the ties with the harness upside-down, and the knots will came out on the bottom when the harness is turned rightside-up.

The harness may now be mounted in the chassis. Hold it in place with a few cable clamps. Metal and plastic clamps are available in many different sizes. The plastic types are not as likely to cut into the cable, and will not cause a short circuit even if they do+

Route the leads to each component and cut them to length, „eave a little extra lead length at the end of each wire. Tins is called a service loop, and is very helpful ii the connection must be taken loose and re-soldered when replacing a component, t also keeps the wire from putting any strain on the connection. It is best to run the wire straight, and then make the loop right at the connection.

Tinning and soldering

All stranded wire must be tinned after stripping. This takes only a few seconds, and if it isn't done, the ends of the wires will fray and spread in all directions when the wire is wrapped around a terminal. Heat the wire before applying the solder, so that when the solder is applied it will quickly flow between the strands.

Strip enough of the wire so that when the connection is made, the insulation will be back about iW or so from the connection. This will help to prevent burning the insulation when soldering. Don t put a sharp bend in the wire within of the connection, as the heat of soldering may cause the insulation to pull away from the wire.

The above applies to the use of most plastic or rubber insulated wires. Teflon insulation is not affected by soldering iron heat, and cannot be burned or melted accidentally. Although Teflon-insulated wire is expensive (about 1 or 5 times the price of vinyl insulation), it is very useful when many wires must be soldered in very close quarters. Besides being heat-resistant, the electrical and mechanical properties of Teflon are excellent.

The proper method oj lacing.

If you wish to replace a wire in (he harness for some reason, you can do so by soldering a new wire to one end, and by pulling the other end the new wire may be drawn into the harness. Make a small lap-type solder joint, and smooth olT any rough edges before pulling it through.

The information given here should not be taken as the last word on the subject. However, the use of this outline, together with ideas of your own, should make it possible for you to do a very professional-looking wiring job on your next project,

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