Zone VI Cold Light Stabilizer - Problem

[John Irvine]

I have a Zone VI cold light with the Zone VI stabilizer. It was my father's and has set around unused since the 80's. It was not used often then. I now have them set up on his Beseler enlarger and suspect there is a problem. I have all the original instructions and Zone VI newsletters discussing it and have a fair idea of the principle. I believe it is all hooked up right. However, it will never stabilize higher than half way between steps C and D. It will not stabilize at all unless I leave the heater and the light both on for 15 or 20 minutes. After being used for a couple of hours, it still won't stabilize higher than between C and D.

I cannot tell that there is any increase in lamp intensity from step C on up. I exposed a test strip for 3 seconds every other step (D, F, H, J, L). I see no difference in tone between any of them.

Is

a. everything doing what it is supposed to?

b. nothing working right?

c. there an incoming voltage issue?

e. a lamp problem?

f. a stabilizer problem?

What can I possibly do to check it out? I am not into electronics other than flipping a switch to turn on a light. However, I do have a simple volt meter.

John

 

[Richard T Ritter]

Answer is "A".
IT should stabilize around the F setting but some stabilize at a lower setting. On preheating the unit when I set up the darkroom for printing I plug the preheated in and turn on the light by turning on the focusing. Best to find a setting where it works and never touch it.

 

[John Irvine]

Thanks. Sounds like it is working then. I start it up the same way you do. I'll just leave it at half past C and make pictures.

 

[Anscojohn]

[I have all the original instructions and Zone VI newsletters discussing it and have a fair idea of the principle.


*************

Hello John,
I will make you rich beyond the dreams of avarice if you will copy the newsletters dealing with this system and snail-mail the copies to me here in Northern Virginia.

 

[eddie]

AnscoJohn- I'm in Alexandria, and have the newsletters, if you'd like to borrow them.

 

[henrysamson]

Mine has to be warm also. When it is it will stabilize up to "E". Used to work up to "F" 20 years ago!

 

[Edwardv]

Could it be the lamp???

 

[John Irvine]

1. For all I know it could be the lamp. Know of any way to check it other than ordering a new one? Where would you get a new one and what would it cost?

2. Anscojohn & eddie - I'm in Orange, half way between Fredricksburg and Charlottesville. Could we meet some where and trade newsletters and take some pictures?

 

[ChuckP]

Mine works at the L setting but it's with an Aristo D2-HI coldlight. Just for kicks try plugging the light directly to an outlet and see if you can see any big change in light intensity. Maybe measure it with a meter. I'd think the stabilizer would allow the lamp output to closely approach the intensity of the directly plugged in lamp. Maybe you could also play with the sensor in the head turning it a different direction from the light.

 

[john_s]

I believe that the Zone VI tubes were made by Aristo (www.aristogrid.com). Their website is not very refined, but I'm sure that an enquiry to them would result in some info about replacement tubes. I think that they make a replacement tube with a better spectral response for VC filters if that interests you.