ANTENTOP- 01- 2007, # 009

Simple Iambic Key on PIC16F628A

Credit Line:

http://ru3ga.qrz.ru/

Kluyihin Alexandr, RU3GA

ra3ggi@mail.ru

This simple key is assembled with a PIC16F628A. Internal controller's generator on 4-MHz provides function of the PIC. The key can work at feeding voltage from 2 to 5.5-V. Some samples of the PIC16F628A may work when feeding voltage drop ever to 1.2-V. Consumption current at working mode is 2- 4-mA (at supply voltage 5-V) and 0.5- 0.8-mA (at supply voltage 3-V). Consumption current at sleeping mode is less the 1-μA.

 So, the key can be fed from a small Lithium battery which may be fed the key (ever without a Power Switch) for several years.

 Specification

 Iambic mode with memory of last item of data

 Iambic manipulator may be reversed with help of buttons

4 memory cells, each one has capacity of 30 letters

 Memory cell can be written by PIC's key. Rewriting resource is 1,000.000 times.

Needed corrections in the entering data may be made during the record

Data in the memory cell keep saved without power supply across the PIC

Keying speed could be adjusted (with help of a variable resistor) from 4-WPM up to 100-WPM.

Sidetone is 800-Hz

Sidetone can turn ON/OFF with buttons

 Simple hand key may be switched on

Ratio "dot- gap- dash" may be chosen with a multipoint switch:

a)0.75-1.25-3

b)1-1-3

c)1-1-3.5

d)1-1-4

e)1-1-4.5

Operation

● Record to a memory cell

 Hold button of needed memory cell for 2 seconds. Speaker transmits "WR"- it means that key stands for the record. At a record the gap between letters the key recognizes automatically. For installation a gap between words you need to do pause in the record for 2 seconds. Speaker transmits "R"- it means that the key is "understood" the gap between words and key is waiting for the record of next data. So, before enter of new data you may drink a coffee or read a book. Key will wait you for the record. When only 3 letters are to finish the memory cell the Sidetone is changed in frequency. To terminate the record tap any button.

● Correction of Data

If an erroneous symbol was entered do transmitting dots in number more than six. Speaker will transmit "R"- it means that key stands in "Correction Mode." After that speaker transmit "Last"+"last right letter" and go to Waiting Mode. Speaker transmits "Last NO" if an error was on the first record letter.

PCB for the Key by DL3MIH

http://www.antentop.org/

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