IF IT DOESN'T WORK

The basic condition for the auto-invert circuit to work is to have achieved successfully the image unlock. That means that you already must have clear and stable image even if it changes its polarity some times. You must also check with a multi-meter (twice) if the appropriate copper lines have been fully cut. Do not trust the way they look, sometimes they might look cut but actually are not.

If your circuit does not work at all in all the coded channels, meaning that you do not see any difference with or without it, first of all read the type and the brand of the chips you use - they must necessarily be "ON" brand ( www.onsemi.com ) and the type should be MC14584BCP and MC74HC74AN. Any other chips will not work at all. If the chips are correct then try to change them with another pair because it has happened to find a burnt one. - Always use bases.

Also count (twice) the pins of the Delta chip to be sure that you have connected the right ones.

If your circuit operates faulty, that means if during the invert period it flashes constantly - and not only once as it should - or if it works ok in one channel but not in the other, then you must adjust the PLL voltage level. As a general instruction, in all the models this can be achieved by turning the trimmer witch is located near the 11 MHz crystal, near the variable coil, near the Delta chip.

Resuming,

Count the voltage level on the trimmer pin witch is alone (not the ones that are connected together). It must be -2.5 to -3Volts . If its not, adjust the trimmer and if this wont do, connect from this pin to the ground a 1K resistor and readjust so the voltage level goes between -2.5 to -3Volts and the circuit works.

Cablecrypt 1: 'R838'

Cablecrypt 2:

Comcrypt 4000 ( Ver 1.3): '3838'

Comcrypt 4000 ( Ver 1.4):

Comcrypt 4000 ( Ver 2.3): 'R838'

Comcrypt 4000 ( Ver 2.4):

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