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  1. #11

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    This is good news. I will definitely be a customer for a spare pair of tubes, although my current ones seem fine. Has anyone had to replace tubes in their VCL4500?

  2. #12
    Curt's Avatar
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    If a complete head could only be made; say a universal 8x10, or 5x7, that would be great. It seems that making the bulb is/was the bump in the road, transformers, switches, metal boxes plastic diffusers and wiring exist and can be spec'd.
    Everytime I find a film or paper that I like, they discontinue it. - Paul Strand - Aperture monograph on Strand

  3. #13
    Ken Nadvornick's Avatar
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    Quote Originally Posted by john_s View Post
    Has anyone had to replace tubes in their VCL4500?
    I know I've mentioned this before, but I do need to replace mine. My unit came to me used with aged tubes. I was told that lamps normally lasted about five years in commercial lab environments - proportionately longer in home use. And as they age the lamps grow dimmer. My exposures are now very long. But the precision and repeatability of absolutely correct, evenly spaced contrast grades makes that more than worthwhile. New tubes will, for me, be a blessing.

    Everyone needs to run the numbers for themselves. But given the unpredictability of everything analog these days, I plan to replace my existing lamp grids, then purchase a second backup set as insurance against accident or premature failure. I may or may not get another chance. YMMV...

    Ken
    Last edited by Ken Nadvornick; 12-20-2010 at 11:39 PM. Click to view previous post history. Reason: That demon spelling...
    "They are the proof that something was there and no longer is. Like a stain. And the stillness of them is boggling. You can turn away but when you come back they’ll still be there looking at you."

    — Diane Arbus, March 15, 1971, in response to a request for a brief statement about photographs

  4. #14
    Ken Nadvornick's Avatar
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    Quote Originally Posted by Curt View Post
    If a complete head could only be made; say a universal 8x10, or 5x7, that would be great. It seems that making the bulb is/was the bump in the road, transformers, switches, metal boxes plastic diffusers and wiring exist and can be spec'd.
    I've had the same thought. When asked about the possibility of a reintroduction of the complete cold light head assemblies, Louise has said that Voltarc is a specialist fluorescent lighting company that has no interest or expertise in manufacturing the physical housings or full electronic control units. Thus, their willingness to reengineer and reintroduce only replacement tubes for existing heads. It's what they do.

    But the thought has crossed my mind that if a different manufacturer - or individual - could be found who was willing to create the housings and spec/source the required electronic components, then use Voltarc merely as the lamp grid supplier...

    Ken
    "They are the proof that something was there and no longer is. Like a stain. And the stillness of them is boggling. You can turn away but when you come back they’ll still be there looking at you."

    — Diane Arbus, March 15, 1971, in response to a request for a brief statement about photographs

  5. #15
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    With Voltarc as a supplier of lamps there would be a great opportunity for someone or some individuals to form a company and make a product. It is a product that's needed and given that it's fluorescent it's an energy saver. An electrical engineer could design the components for a small company to assemble. It would be fairly green and would create jobs and revenue, all are pluses and we the consumer could get back to our business of making prints.
    Everytime I find a film or paper that I like, they discontinue it. - Paul Strand - Aperture monograph on Strand

  6. #16
    Ken Nadvornick's Avatar
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    When I opened up the controller unit and head I found they contained a rather smallish number of old-school, discreet electrical components. You know... single resistors and capacitors, a pair of large iron-core transformers (where the 10-pound weight comes from), relay switches, wires, connectors. Stuff like that.

    I think there was a single early IC chip in mine mounted on a primitive circuit board. Looked almost like an old Heathkit contraption. My assumption was that the IC probably drove the simple digital display.

    These Aristo units were designed and manufactured a long time ago. And before the era of planned obsolescence. For someone who knows discreet components it probably would not be a difficult task at all to functionally replicate the specs. Unfortunately, I'm not that person or I'd try it myself.

    And who knows? Perhaps Louise would have access to a bit of residual documentation. After all, if Voltarc had no further interest in it...

    Ken
    "They are the proof that something was there and no longer is. Like a stain. And the stillness of them is boggling. You can turn away but when you come back they’ll still be there looking at you."

    — Diane Arbus, March 15, 1971, in response to a request for a brief statement about photographs

  7. #17

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    The Aristo web site used to have a downloadable instruction manual for the VCL4500 and in that there was a circuit diagram for the controller. Not all voltages were specified, but it would not be difficult to reverse engineer. The only tricky part for me would be the section that produces the digital readout, but that could even be dispensed with, and just rely on the knob position for grades.

    I have checked and found that the doc is still at the aristo web site mentioned above. There are other docs, including the one for mounting a light sensor* for compensating timers. These exist because cold light heads change their output as they warm up. However the VCL4500 tubes are much better in this regard than the old graded paper single tube models of years ago.

    * This is still labeled erroneously as "temperature probe installation". This is the sensor used for Zone VI compensating timers and also the marvelous RH Designs Stop Clock Vario. For do it yourself types, the sensor is
    EG+G Vactec VTB8440BH photodiode with IR filtering.

    More info at
    http://uk.farnell.com/eg-g-vactec/vt...0?Ntt=118-2340

    Wire it so that the pin with the polarity dot goes to the outer pole of the jack plug (for RH Designs fitting).

    For the Zone VI fitting, I can look it up if anyone is interested.
    Last edited by john_s; 12-22-2010 at 03:26 PM. Click to view previous post history.

  8. #18
    Ken Nadvornick's Avatar
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    Quote Originally Posted by john_s View Post
    The only tricky part for me would be the section that produces the digital readout, but that could even be dispensed with, and just rely on the knob position for grades.
    This was the Dr. Horowitz/Zone VI design approach. Cleaner, simpler, more reliable, less things to go wrong. I've used a Zone VI Compensating Enlarging Timer with just click stops and loved it.

    Quote Originally Posted by john_s View Post
    This is the sensor used for Zone VI compensating timers and also the marvelous RH Designs Stop Clock Vario. For do it yourself types, the sensor is EG+G Vactec VTB8440BH photodiode with IR filtering.

    More info at
    http://uk.farnell.com/eg-g-vactec/vt...0?Ntt=118-2340

    Wire it so that the pin with the polarity dot goes to the outer pole of the jack plug (for RH Designs fitting).

    For the Zone VI fitting, I can look it up if anyone is interested.
    This is a really good piece of information. I kept a spare one of these in a baggie for many years until installing it into my used VCL4500. I've always worried what would happen if it, or the one in my Zone VI single-lamp head, ever failed. I had no idea where to look for a replacement. Now I know. And so does the APUG Archives. Thanks so much, John.

    Ken
    "They are the proof that something was there and no longer is. Like a stain. And the stillness of them is boggling. You can turn away but when you come back they’ll still be there looking at you."

    — Diane Arbus, March 15, 1971, in response to a request for a brief statement about photographs

  9. #19
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    Interestingly enough I opened a 5x7, well actually the diffuser frame comes right off, now the bulb is dimmer than it should be but there is no heater circuit and it's a single cord plug-in box. It does have a toggle switch. It's old and really simple. My 2 1/4 head, 4X5 square head, round Beseler head all have heater circuits. I do have a 10X12 unit with a separate control box with a dimmer knob on it. It functions very well and was probably some kind of a light box. Aristo couldn't tell me what it was for even with supplied serial numbers. I never knew if it would work on an enlarger so it sits in a box. I should make a viewer out of it I suppose.

    I've blown more than my share of money on Aristo heads. I finally switched to a Beseler color head rewired for new 120 volt lamps in the same color temperature as the 82 volt ones. I wanted to get a duel bulb Aristo for my 5X7 Durst but now I'm going to have to make a diffusion head for variable contrast BW paper.

    The older I get the less I hope and the more I act.

    Curt
    Everytime I find a film or paper that I like, they discontinue it. - Paul Strand - Aperture monograph on Strand

  10. #20

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    John_s,if you do have the ref. or Id number for the zone x1 light probe I would like it . Thankyou

    Mike

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