Re: Remote Fan Controller (IR)

Ok, Step further now.
With both the fan and light disconnected (but power applied), checked with a
DC Voltmeter the voltage going to the IR receiver (and the single chip on
the controller board). Getting a nice stable 6 volts.

But when i press a button to turn the fan on, the voltage drops to about 3
volts (within 2 seconds).
During the time that the voltage is dropping, the receiver still responds.
but after that 2 sec time, it no longer responds.

There is 1 transistor that runs the light circuit, and 3 transistors for the
fan circuit. Pulling the 3 fan transistors, and then trying, the voltage
does not drop, and the receiver keeps on responding.

Looks to me like the trannies are drawing to much power, and loading down
the low voltage.

The circuit does not have any transformer, so it looks like it has another
way of reducing the mains voltage down to the 6v.

I have replaced all the caps I had stock of, and all the resistors check
within range.
Can anybody venture at a guess of whether there is a problem in the tranny
stage, or in the power reducer (not being able to supply current under the
load of the chip driving the trannies)

Thanks
P


"Theo Markettos" <theom+news@xxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:yGt*nOcXr@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Peter K <peter@xxxxxxxxxxxxxxxxx> wrote:
The 3 have the problem as follows:
Light Brightness works fine, until you switch the fan on.
once you switch the fan on, it operates at the speed you selected,
but then the receiver stops responding [the piezo buzzer in the receiver
does not even beep to indicate that
it received a valid button press.] , and just holds the same state
(Brightness and Fan Speed).

I wonder whether the fan is generating enough noise to crash the
microcontroller? Perhaps a suppressor has gone, or the power supply drops
out enough to crash it when the fan's running? I'd look at the supply
rails
on a scope to see what happens.

Just a thought...

Theo


.

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