Timer/Enlarger...delay with activating light

[paul ron]

thats right. she had someone handy n electronics to help her... via emails we came up with an led replacement but she never used it or managed to get someone to replace it wether led or original. she just said it was repaired.

then another person had the same exact problem here in nyc. i had the unit here n installed an led phoebe was suposed to use. i dont remember the part or the resistor to make it work. once the optoisolator was installed, it worked perfectly.

 

[michaelorr]

Yes, a relay would have been a much better analogy than a transformer.

I think that should be true, upon confirming that the resistance of the photo detector in the new LED opto-isolator gets below the value that it needs to activate the triac. What I don't know is what that value is, and if the substitute component will be sufficient.

Honestly, thinking through this more, without a true RMS reading AC voltmeter, and without some guide as to what the potentiometers R7 and R2 do, I am not really sure I know what it will take to confirm that the lamp is operating at 87v RMS. It may turn out that somehow an incandescent bulb will have to be put in place of the 87v lamp by means of some test jig cabling. This, to avoid destroying an expensive projection lamp. Instead use a 300W incandescent bulb . Bulb that big will be a monster. GE has one that is not a 3-way bulb. It will be mighty bright and mighty hot! And, I don't know enough about bulbs or the circuit to know if the GE bulb will sit in the circuit the same as the 87v lamp - if the resistance is different does that change the operation of the circuit? It may be that one has to take a "ham radio" approach by doing something like wiring 10 330 ohms resistors each 25 watts, and putting into an empty paint can filled with oil to dissipate the heat.

If you or someone else has some experiences to share with trying a part substitution due to part obsolescence, that may help determine the need to "realign" the power supply control board to get the lamp into its operating range.

 

[CMoore]

Would it be possible to just ditch that whole mess, build a (much simpler) stand-alone unit, and then use THAT to supply the lamp with a Regulated Volts-DC supply.?
You guys Have WAY MORE Electronics Knowledge than i do, but.....I cannot get over the feeling that this circuit is way more Complex and Parts heavy than it needs to be.?
Maybe i am wrong, but isn't the main purpose to supply a regulated power supply for the lamp, so that it gives a constant exposure.?
If i had an 87 Volt, Regulated DC supply, that would handle the current draw of the lamp, couldn't i just plug THAT into my timer.?
Thank You

 

[mshchem]

Would it be possible to just ditch that whole mess, build a (much simpler) stand-alone unit, and then use THAT to supply the lamp with a Regulated Volts-DC supply.?
You guys Have WAY MORE Electronics Knowledge than i do, but.....I cannot get over the feeling that this circuit is way more Complex and Parts heavy than it needs to be.?
Maybe i am wrong, but isn't the main purpose to supply a regulated power supply for the lamp, so that it gives a constant exposure.?
If i had an 87 Volt, Regulated DC supply, that would handle the current draw of the lamp, couldn't i just plug THAT into my timer.?
Thank You

Chip you hit the nail on the head. Beseler wanted the "Paper Saver " feature. If you focus with the white light lever engaged, turn off the focus button on your timer, then hit expose the lamp won't light. This saved the operator from exposing a sheet of paper without the filters engaged. I think this may be a reason why there is so much on the board. I know I have read where someone bypassed the board. The fan operated by the master power switch, the lamp power supply he rigged up ran off a regular enlarger timer. Your approach makes perfect sense to me. I built a tachometer in 9th grade from a kit, so that's my limit of electronic work, other than these damn color heads. Freestyle sells the new version for 2300 bucks. Mike

 

[michaelorr]

Well, someone has to be the first..... if someone comes on the thread and says that they have successfully done some sort of substitution, and they didn't have to re-adjust, and the lamp has not burned out, then it is probably a good thing to pursue. Certainly cheap. Check into whether it is possible to get an affordable new updated board that Beseler says would fit into the older head. That would be cool. That resistor can is not the hardest thing in the world to make, and getting connectors and adapters to do a test and alignment jig is not the impossible project. This kind of stuff is done all the time in other projects. In some circumstances it is called prototyping or breadboarding. Alignment and test is a normal procedure in just about all non-digital electronics circuits.

Not encouraging you to proceed or to give up, just keep your options open to further exploration. It looks here like someone has done the mod successfully. If they did it without recalibration and have not burned a lamp out, then follow the steps outlined and it will probably work. If it doesn't, you have not harmed anything.

Not sure you will find a regulator/conditioner that you will have enough info on to adapt. I have a LPL 4500 with an outboard control/supply that may work great for what you want to do, you just need to know what all the pins on that funky connector do up to the head to adapt. Worth a look into though. I dont' know how easy it will be or costly to find one in working order separated from the rest of the enlarger.

 

[michaelorr]

Well, someone has to be the first..... if someone comes on the thread and says that they have successfully done some sort of substitution, and they didn't have to re-adjust, and the lamp has not burned out, then it is probably a good thing to pursue. Certainly cheap. Check into whether it is possible to get an affordable new updated board that Beseler says would fit into the older head. That would be cool. That resistor can is not the hardest thing in the world to make, and getting connectors and adapters to do a test and alignment jig is not the impossible project. This kind of stuff is done all the time in other projects. In some circumstances it is called prototyping or breadboarding. Alignment and test is a normal procedure in just about all non-digital electronics circuits.

Not encouraging you to proceed or to give up, just keep your options open to further exploration. It looks here like someone has done the mod successfully. If they did it without recalibration and have not burned a lamp out, then follow the steps outlined and it will probably work. If it doesn't, you have not harmed anything.

Not sure you will find a regulator/conditioner that you will have enough info on to adapt. I have a LPL 4500 with an outboard control/supply that may work great for what you want to do, you just need to know what all the pins on that funky connector do up to the head to adapt. Worth a look into though. I dont' know how easy it will be or costly to find one in working order separated from the rest of the enlarger.

 

[paul ron]

my approach is broken cant be more broken... so why not try?
worst case it works or burns. so 50% chance of survival is worth a few bucks.

being you have an original part... why not hook up an ohm meter on the photocell and usind a variable power supply, read the voltage and draw the neon light requires? these parameters should be enough to find a sub.

 

[CMoore]

OK...i will "start" looking into it.
Realistically, I would be happy to have a working power supply by Christmas, but who knows.
Thank You Guys AGAIN...for ALL of the help.

 

[paul ron]

Here is an option to fix that vactrol.... replace the neon bulb inside the can by opening it up and using this bulb in place of the old...... then glue or tape the can back together again.

http://www.topbulb.com/eiko-40002-a...rm-base-bulb?gclid=COLOxbaz0tMCFdCPswodG_oPBg

for some reason the bulb link doesnt work in my posts.

the cds is 1.2 meg dark and goes low when lit.

 

[Sirius Glass]

Hold a card over the paper until the light is fully on and then start your timing.

 

[CMoore]

How do you do that...it varies each time you hit the timer button.?
You would have to ditch the timer and just turn the light on and off manually.

 

[Sirius Glass]

Count out loud.

 

[CMoore]

That is what i am saying....You COULD use any enlarger without a timer, but it sure seems a Big Convenience/Tool

 

[paul ron]

the neon light in the vactrol probably flickers or doesnt light bright enough when active.

the unit has worked fine for everyone that replaced that part.

im going to lite it up later to see at what voltage it comes on. we fgured tge voltage at the bulb is aprox 80v.

 

[mshchem]

I have replaced an iso 2 that is a square black plastic cube. I think this is what Beseler used for repairs (guess ) it is labeled CLM3700 378. I found a datasheet online I don't know if this is an option. I replaced it with the Vactrol and the board works fine. See earlier picture.
If I was the original poster I would save the two good Vactrol iso(s) and find another head. Every head I have fixed (4) has been corrected by replacing iso 2 with the original part.
Mike

 

[mshchem]

I have replaced an iso 2 that is a square black plastic cube. I think this is what Beseler used for repairs (guess ) it is labeled CLM3700 378. I found a datasheet online I don't know if this is an option. I replaced it with the Vactrol and the board works fine. See earlier picture.
If I was the original poster I would save the two good Vactrol iso(s) and find another head. Every head I have fixed (4) has been corrected by replacing iso 2 with the original part.
Mike

Looks like the manufacturer of the CLM 3700 was Calogic. It's got a website maybe they could help find something, get you a datasheet.

 

[CMoore]

I have replaced an iso 2 that is a square black plastic cube. I think this is what Beseler used for repairs (guess ) it is labeled CLM3700 378. I found a datasheet online I don't know if this is an option. I replaced it with the Vactrol and the board works fine. See earlier picture.
If I was the original poster I would save the two good Vactrol iso(s) and find another head. Every head I have fixed (4) has been corrected by replacing iso 2 with the original part.
Mike

Hey Mike -
Just to make sure i follow you.......are you saying, when your head has had this problem, you replaced iso #1 and #2.?
Thank You
chip

 

[mshchem]

Hey Mike -
Just to make sure i follow you.......are you saying, when your head has had this problem, you replaced iso #1 and #2.?
Thank You
chip

Just iso 2.

 

[mshchem]

Chip ,
The extra board I sent you is perfect . Just swap that out with your original board and see what happens .
I tried that board it works fine .

 

[Larry the sailor]

Interesting thread. I have the same issue with my old style Dichro 45.
Watching to see if there is an off the shelf solution found.
I've started working on electronics like this in 1980 but he last couple of decades I've been mostly digital. I did have to do a disassemble and clean when I got this thing last year. The delay has been a minor annoyance and a couple of times I've been tempted to drag out the condenser head I got with the enlarger.

 

[RalphLambrecht]

Beseler 45.
Three different timers.

I have tried to find a pattern, but i do not see one.
Does not seem to matter if the enlarger is cold or hot...moving/pulling the power cord from timer to enlarger has no effect...pushing the timer button Hard/Easy/Slow/Fast makes no difference.

What is happening is that the light in the enlarger is coming on at all different times.
Sometimes it comes on as soon as i hit the timer button, other times it may take 1-2-3 seconds for the light to come on.
Does this problem sound familiar to any of you guys.?
Is this user error...have i got something wrong in my procedure or set-up.?
Thank You
do i need a new lamp...or do i have some dirty contacts in the enlarger.?

I had this with my Durst L1200 and I think it's rather common. In my case the culprit was the voltagestabilizer which took 300ms to fire up.Fortunately, my timer could be adjusted to account for the delay(RHDesigns custom chip).

 

[Des White]

Just reviving this thread in case anyone still encountering this very annoying problem - I bought a dual dichro head, it suffered the delay issue, but I can confirm that installing a new optocoupler - LED model VTL-5C3 solved the problem with no other modification required, as stated by Phoebe's tech years ago. $5 from ebay, not a complicated job, hardest part is removing the old 4 pin coupler from the board without melting anything, just go slow and you'll be fine ... here is the link. Message me if you need any help.

https://www.ebay.com/itm/1Pcs-VTL5C3-xvive-audio-opto-coupler-high-qualityB9/193170231900?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

 

[CMoore]

Just reviving this thread in case anyone still encountering this very annoying problem - I bought a dual dichro head, it suffered the delay issue, but I can confirm that installing a new optocoupler - LED model VTL-5C3 solved the problem with no other modification required, as stated by Phoebe's tech years ago. $5 from ebay, not a complicated job, hardest part is removing the old 4 pin coupler from the board without melting anything, just go slow and you'll be fine ... here is the link. Message me if you need any help.

https://www.ebay.com/itm/1Pcs-VTL5C3-xvive-audio-opto-coupler-high-qualityB9/193170231900?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

There are 1 or 2 little trim pots on that circuit board. Anybody know How/What voltages those are supposed to control.?

 

[John51]

Would it be possible to just ditch that whole mess, build a (much simpler) stand-alone unit, and then use THAT to supply the lamp with a Regulated Volts-DC supply.?
You guys Have WAY MORE Electronics Knowledge than i do, but.....I cannot get over the feeling that this circuit is way more Complex and Parts heavy than it needs to be.?
Maybe i am wrong, but isn't the main purpose to supply a regulated power supply for the lamp, so that it gives a constant exposure.?

If i had an 87 Volt, Regulated DC supply, that would handle the current draw of the lamp, couldn't i just plug THAT into my timer.?

Thank You

Mains voltage can vary and that will give the bulb a different colour temperature. Not enough difference to be a problem printing b+w but for RA4, a stabilised supply is advised.

Easiest way to get 87v to the bulb is to use a variac. Mains > variac > bulb. For b+w, use a dmm to establish 87v output and leave it at that setting. For RA4, establish 87v just before making each print.

 

[Thomas S]

Just reviving this thread in case anyone still encountering this very annoying problem - I bought a dual dichro head, it suffered the delay issue, but I can confirm that installing a new optocoupler - LED model VTL-5C3 solved the problem with no other modification required, as stated by Phoebe's tech years ago. $5 from ebay, not a complicated job, hardest part is removing the old 4 pin coupler from the board without melting anything, just go slow and you'll be fine ... here is the link. Message me if you need any help.

https://www.ebay.com/itm/1Pcs-VTL5C3-xvive-audio-opto-coupler-high-qualityB9/193170231900?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Just to make sure I understand before attempting this, there is no extra resistor required to account for differences between the LED vs neon lamp power requirements? This sounds quite doable!