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Odd IC chip.
- Thread starter Staybolt
- Start date
Never seen one, but I remembered someone here asking about a radio that used that chip before. In that case it was the Standard Horizon 29A, which is in Sam's CB-94.
The uPD857 appears to be a programmable counter and divider, and not much else. The programmable divider is what your channel selector is connected to, and in the 29A that was pins 1, 2, 3, 4, 5, 6, 8, and 9, for a total of 8 pins.
I do not know if the uPD857 is set up for straight binary programming, or for BCD. You'd need to have or create a truth chart to figure that out.
It's probably modifiable for more channels by manipulating the programmable divider inputs, as it's way too early a chip to have a ROM component.
TL;DR It's a generation older than the uPD858. Not similar enough to use the same mods, but you can create your own.
The uPD857 appears to be a programmable counter and divider, and not much else. The programmable divider is what your channel selector is connected to, and in the 29A that was pins 1, 2, 3, 4, 5, 6, 8, and 9, for a total of 8 pins.
I do not know if the uPD857 is set up for straight binary programming, or for BCD. You'd need to have or create a truth chart to figure that out.
It's probably modifiable for more channels by manipulating the programmable divider inputs, as it's way too early a chip to have a ROM component.
TL;DR It's a generation older than the uPD858. Not similar enough to use the same mods, but you can create your own.
