Re: Speed control

[Dave Everett <deverett@idx.com.au>]

At 22:03 15-05-99 -0700, Dick Morrisson wrote:
>Dave,
>Thanks very much for the link.  I found a PWM (it happens to use MOSFET's
>though) which will supply a 12vdc motor with up to 35 amps for only $63.  I
>don't suppose you think even $63 is high for such a device, do you?  I had
>found a surplus unit available for $25 but the source was soon to dry up
>(can't use a "dried up" controller on an underwater propulsion unit now can
>we!) and I was expecting the normal price of a similar unit to be over $100.
>Now I feel a bit more comfortable designing around the variable speed
>concept.  I have high hopes of making an underwater propulsion unit which can
>be marketed at significantly less cost than those currently for sale.
>Quantities will likely be low for at least awhile so an off the shelf item is
>very nice to deal with.
>Thanks again,
>Dick Morrisson
>
I'd definitely go with the readymade board. Making one-off boards is an
expensive proposition. You could never make a single board for the price
you quoted above.

Dave Everett.