building analog electric gauge with FSBUS

[Guest stevelep]

I want to use analog electrical gauge like needle-galvanometer to display current and voltage with FSBUSAny idea how to proceed ?My idea was to use a servo link to a pot to drive the current in a circuit and use the galvanometer in serial to measure the amps.may be there's more simple like a circuit who convert the impuls of the servo command in amps or voltage ?BOB

[Guest mbessler]

>I want to use analog electrical gauge like>needle-galvanometer to display current and voltage with FSBUS>>Any idea how to proceed ?>>My idea was to use a servo link to a pot to drive the current>in a circuit and use the galvanometer in serial to measure the>amps.>>may be there's more simple like a circuit who convert the>impuls of the servo command in amps or voltage ?>>BOBIf I understand you correctly, you want to drive a galvanometer instrument directly from FSBUS so it will eg. show the Voltage/Amps of some internal value from the simulator...Does FSBus have an Analog-Out ?The simplest way to do this is to use PWM, very similar to how the servo controller works.A software change in the servo controller that modifies the duty cycle to work from 0 to 100% might do it. Servos, on the other hand, need a 1-2ms 'on', repeated about every 20ms. This would translate to 5-10% duty cycle.Manuel

[Guest stevelep]

FSBUS don't have analog out that why I'll use a servo to turn a potwhat's PWM ?BOB

[Guest mbessler]

>FSBUS don't have analog out that why I'll use a servo to turn>a potseems a little complicated, using a servo to turn a pot which sets the voltage for the instrument pointer.Have you asked Dirk about this ?For small galvanometer instruments, the servo board as-is, but with a different firmware should be able to do what you need.I'll do it similarly with my PHCC (PIC Homecockpit Controller)>what's PWM ?Pulse Width Modulation. Used for servos, to do Digital-to-Analog Conversion, for Switching power supplies,...google for "pwm servo" this should give you some info on the basic technique.Manuel