Zone VI variable contrast cold light head

**sanking** · 13-Dec-2022, 19:52

Does anyone know where one might find an electronic schematic for a 5X7 (13X18 cm) cold light head? I have a friend in Spain who needs to have some adjustments made to one he has been using for many years and thinks he might be able to have it fixed in Spain if he can located a schematic.

Thanks for any information or contact person who might have some information on this subject.

Sandy

**Paul Ron** · 13-Dec-2022, 20:09

I searched the net but no schematics. I dont know what your symptoms are but.... One manual I read with an overview of the system says there is a sensor for each of the 2 bulbs... more than likely photo diodes. Perhaps start there with a meter to see if they are functioning?

Do the lights come on?

Im sure someone here will be more familiar if you gave more details of the symptoms n problems? Pictures also help when describing problems too.

**neil poulsen** · 14-Dec-2022, 10:20

It doesn't seem like the circuits in these heads would be that complicated. (Though, I've never opened one.) It may be a reasonable option to have someone trace the circuitry and construct a schematic from scratch.

**RichardRitter** · 14-Dec-2022, 11:23

Originally Posted by neil poulsen

It doesn't seem like the circuits in these heads would be that complicated. (Though, I've never opened one.) It may be a reasonable option to have someone trace the circuitry and construct a schematic from scratch.

Only one problem. Some of the parts in the head had the marking removed . I reached out the the people who were building the units a few years ago and was told they no longer had any info on the heads or parts and would not help at all. Sounded like they signed a nondisclosure.

**Tin Can** · 14-Dec-2022, 11:37

I am now using Intrepid 4X5 LED Head on DeVere

Timer, safelight, variable in many ways

They offer 3 variation panel, one for DeVere which requires an adapter they supply

https://intrepidcamera.co.uk/collections/darkroom

**sanking** · 14-Dec-2022, 20:45

Thanks for all the replies. I was hoping that a schematic would have been saved somewhere, but alas that does not seem to be the case.

I will pass the word on to my friend. The problem he has is that the soft light does not come on at all, but the hard one does.

Sandy

**Paul Ron** · 15-Dec-2022, 07:29

maybe a bad tube, or the balast is bad, or maybe something something as simple as a bad connection. open the unit and check it out. its a very simple circuit.