analog board
analog board
analog board not switching between tlo82 a and b. can only calibrate 3.3v side (tlo82b). might be the tlo82 or the 74hc4053. i don't have the tools to remove the old chips. any one else have this problem.
Re: analog board
Suggestion:
1 ) First verify at pin 11 of U2 whether signal SENSEL3 is good.
2 ) Check U1A and U1B by looking signal at V1 and V2. V2 is normally very small. Parallel R3 with a small resistor (10K for example) to make the signal larger. You can check by average voltage (measured with DC volt-meter) if you do not have another scope.
3 ) Bypass U2 pin12 -- pin14 and pin13 -- pin14 respectively to verify U2.
1 ) First verify at pin 11 of U2 whether signal SENSEL3 is good.
2 ) Check U1A and U1B by looking signal at V1 and V2. V2 is normally very small. Parallel R3 with a small resistor (10K for example) to make the signal larger. You can check by average voltage (measured with DC volt-meter) if you do not have another scope.
3 ) Bypass U2 pin12 -- pin14 and pin13 -- pin14 respectively to verify U2.
Re: analog board
thanks for your response. i found the error of mine it was in the resistor divider stage between resistors 7 to 12. one resistor was not soldered to board.