range hood insanity (mot microcontroller)

[bluto]

Re: range hood insanity (mot microcontroller)

Well I ordered a resonator. I will give that a shot before go slicing the board up to add pots and switches.

[ratdude747]

Re: range hood insanity (mot microcontroller)

i meant buying a breadboard (solder kind) and building it that way.

[bluto]

Re: range hood insanity (mot microcontroller)

Gotcha. I was thinking along the lines of reworking the original board and thus being able to use the triacs, comparator, original connector, etc. I am guessing that it would be possible to use two pots to supply 0-5v variable to the input channels on the comparator IC. In that case the lights and fan should dim just as they do now, but with a knob instead of a button and no fancy bar graph.

[hardwareguy]

Re: range hood insanity (mot microcontroller)

The sad thing is I could even get the bargraph to work with a good old fashioned analog circuit.


You need a bargraph driver IC and a voltage divider or potentiometer to calibrate it.

[ratdude747]

Re: range hood insanity (mot microcontroller)

yeah, i meant re-use parts from the dead board to make a new circuit on the breadboard. makes reworking in the future less of a problem.

[stj]

Re: range hood insanity (mot microcontroller)

resonators are junk - only good for tv remotes.

try a 4mhz crystal.
i had a whole bunch of usb keyboards that would stop working after a while - i found they all had a 6mhz resonator.
*but* the pcb was marked for a crystal - fitted crystals and they ran sweet.

[bluto]

Re: range hood insanity (mot microcontroller)

It looks like another successful repair! I put the new resonator in and the all the above mentioned issues are gone. I also put in two new proper sized caps (I had swapped in some for troubleshooting that were a higher voltage rating) and put it all back together. I have never really paid much attention to the small anonymous components like the resonator, but can now see how they can cause big problems. Here are digikey part numbers in case you have problems with your broan range hood:

4mhz resonator w/cap (X902-ND)
470uf 10v capacitor (P10221-ND)
470uf 16v capacitor (P10248-ND)

Should cost around $1.50 for these three parts.

Thanks for all the helpful replies on this thread.

[shadow]

Re: range hood insanity (mot microcontroller)

Congratulations....that was an interesting project you undertook thou!

[Agent24]

Re: range hood insanity (mot microcontroller)

On a side note, my TV remote went off into happy-land recently.

Turned out the problem there was also a bad resonator, one of the pins had snapped (why are they thin and flat and easy to break?)