Introduction
The Radio Adventures Co. C1A advanced CMOS Iambic Keyer/Controller is a high performance, low cost preprogrammed microcontroller specifically developed for the amateur and commercial communications markets.
The C1A combines iambic keying functions with timing and sequencing features in a single chip and provides a convenient way to key and control home built and commercial transmitters and transceivers. In addition to iambic keying features, the C1A also supports the use of a straight key and a semi-automatic key (bug) and provides a bug like mode using single or double lever paddles.
Features
- Iambic A and B operation, selected by raising or lowering the MODE pin.
- Bug Mode using single or double lever paddles. When the DIT contact is closed, dits are generated automatically at the speed selected by the speed control. When the DAH contact is closed, the transmitter is keyed until the dah contact is opened. If the MODE pin is held high, spaces, the length of which is determined by the speed setting, are inserted after each dit and dah. If the MODE pin is held low, spaces are only inserted after each dit.
- Straight Key Mode. A separate input is provided for a straight key, tune switch or bug. When this input, SK, is held low the transmitter is keyed. As with the Bug Mode, if the MODE pin is held high, spaces, the length of which is determined by the speed setting, are inserted after each key opening. If the MODE pin is held low, spaces are not inserted after each key opening. In all cases, the key closure and key opening is debounced. This is especially useful when using a bug with modern high transfer speed full break-in rigs.
- Speed range is continuously adjustable over the range of 10 to 40 WPM and is crystal controlled for high accuracy over the full voltage and temperature range. (Ceramic resonator supplied with part)
- Adjustable Spacing. Spacing is adjustable to provide compensation for transmitters which distort the keying waveshape. Standard 1 dit spacing is available by connecting the SPACE input directly to VDD.
- Adjustable weight. Dah weight is adjustable to provide compensation for equipment that distorts the dah to space ratio. Standard 3 to 1 weight is available by connecting the WEIGHT input directly to VDD.
- Adjustable Sidetone. The C1A provides adjustable sidetone output sufficient to drive headphones or an efficient speaker. The frequency is variable from approximately 500 hz to 1 Khz. 750 hz output is available by connecting the PITCH input to VDD.
- Built-in Transmit sequencer. Three outputs are available to provide full and semi break-in keying control. When any key input is closed after 3/4 of a second or more of no activity, the SEMI output pin goes low and stays low until approximately 3/4 of a second after the last element is sent. When any key is closed, the ANT pin goes high 5.5 mS before the TX pin goes high. When an element is complete, the TX pin goes low immediately and then the C1A tests INTERLOCK pin which is optionally driven externally. 5.5 mS after INTERLOCK goes high the ANT pin is lowered. This sequencing provides for antenna transfer, VFO shifting, receiver muting and transmitter keying in both full and semi break-in modes. Approximately 3/4 second after the last element is sent, SEMI output pin goes high and the C1A sleeps. That is it goes into a very low power mode.
- Full CMOS Technology. The C1A operates over the range of 3 to 6 volts, 0 to 70 degrees C. Without sidetone, operating current is approximately 1.5 mA and sleep current is typically less than 5 uA, making an on-off switch unnecessary in many cases. Operating current may be slightly higher when the sidetone is producing full output or when driving keying and control transistors.
- High Output Drive. The C1A provides more than 10 mA output current which is adequate to directly drive switching transistors and the sidetone monitor speaker through a matching transformer.
Pricing/Ordering
|
Description |
Price |
|---|---|
| C1A CMOS Iambic Keyer Chip w/ 2.0 MHz resonator, DIP-18 | $14.95 |
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