Dew heaters and Skywatcher 150

[gajjer]

I had a real problem with dew one night a few weeks back. My remedy was to blast the main mirror with a hair drier.

So I was thinking about dew heaters. On a quick search I found some gen on SCT scopes but not on reflectors.

So my question is; where would you fit dew heaters and what does that do to thermal turbulence in the tube?

Also, I have several small fans from old computers etc. Would that be an alternative and is vibration something to be considered?

Thanks

gaj