Heljan O gauge - noisy fan

[norman]

Newer Heljan Diesels have the fan control module incorporated into the main DC board which is redundant when fitting DCC.

Using a Zimo MX699KS in a class 33 and hooking the fan to the 5 volt supply produces a fan that runs fast and makes a considerable noise.  So I've dimmed it down  to reduce the speed to an acceptable level but it it is still too noisy.  

The Heljan analogue board with a voltage regulator and a potentiometer produces a far better result with good fairly quite running.

Are the separate fan control boards available i.e. the ones that Heljan fitted in the roof in earlier models?

 

Is there another way with a DIY solution to achieve the better result?

Edited November 1, 2021 by norman
added photo

[Hal Nail]

12 hours ago, norman said:

 

 

Are the separate fan control boards available i.e. the ones that Heljan fitted in the roof in earlier models?

 

 

Worth putting something in the wanted section? I've seen a few people say they always isolate the fan anyway.  

[47606odin]

I’ve disconnected all my fans, they are indeed noisy, and at the end of the day a gimmick that you can’t see unless you are specifically looking down in the door for. You can use the CV output for something more constructive like a headlight seperate from route indicator lights I guess