Heathkit IT-12, Инструкция по сборке

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Leads on resistors, capacitors and transformers are generally much longer than they need to be to make the indicated
connections. In these cases, the excess leads should be cut off before the part is added to the chassis. In general, the leads
should be just long enough to reach their terminating points. Not only does this make the wiring much neater but in many
instances, the excessively long leads will actually interfere with proper operation of the instrument.
Space has been provided for you to check off each operation as it is completed. This is particularly important in wiring
and it may prevent omissions or errors, especially where your work is interrupted frequently as the wiring progresses.
Some kit builders have also found it helpful to mark each lead in colored pencil on the pictorial as it is added.
Unless otherwise indicated, all wire used is insulated. Wherever there is a possibility of the bare leads on resistors and
capacitors shorting to other parts or to chassis, the leads should be covered with insulated sleeving. This is indicated in the
instructions by the phrase "use sleeving." Bare wire is used where the lead lengths are short and the possibility of short
circuits are non-existent.
ROSIN CORE SOLDER HAS BEEN SUPPLIED WITH THIS KIT. THIS TYPE OF SOLDER MUST BE USED FOR
ALL SOLDERING IN THIS KIT. ALL GUARANTEES ARE VOIDED AND WE WILL NOT REPAIR OR SERVICE
EQUIPMENT IN WHICH ACID CORE SOLDER OR PASTE FLUXES HAVE BEEN USED. IF ADDITIONAL
SOLDER IS NEEDED, BE SURE TO PURCHASE ROSIN CORE (60:40 or 50:50 TIN-LEAD CONTENT) RADIO
TYPE SOLDER.
PROPER SOLDERING PROCEDURE
Only a small percentage of Heathkit purchasers find it necessary to return an instrument for factory service. Of these, by
far the largest proportion function improperly due to poor or-improper soldering.
Correct soldering technique is extremely important. Good solder joints are essential if the performance engineered into the
kit is to be fully realized. If you are a beginner with no experience in soldering, a hall-hour's practice with odd lengths of
wire and a tube socket will be a worthwhile investment.
If terminals are bright and clean and wires free of wax, frayed insulation and other foreign sub-stances, no difficulty will
be experienced in soldering. Crimp or otherwise secure the wire (or wires) to the terminal, so a good joint is made without
relying on solder for physical strength.