However, after overcoming that initial hurdle ... it occurred to me that I faced another "bigger" one: We have over 350 members in our group now and a little under half of them receive our newsletter and, of those, about 120 receive the "hard copy". The balance opted for Jack Gildar's kind offer to supply the text of Organ Notes via Email (at no cost to the recipient). Of course, some folk had no choice (no computer!).. Anyway ... of those receiving "printed" versions of our newsletter ... most have a number of issues that are still due them and most folks haven't supplied SASE's. They originally sent STAMPS (most of which I, not looking ahead, used in my correspondence with folks in the group and if we made the change today ... I'd have to send Bill a large bunch of 1st. class stamps. I owe just a few issues to most folks but I'm asking that everyone will RELEASE me from those obligations. If you have any OBJECTIONS to doing so (hardship, etc) please write to me immediately because I DO WANT TO BE FAIR. If I don't hear from you, I'll assume that you've agreed to release me from those obligations. In the FUTURE please send items for our newsletter and/or any info, questions, etc., that apply to the Schober group, to:
FROM NOW ON I'M ONLY ANOTHER SCHOBER GROUP MEMBER! However ...
if you have any "immediate" questions, etc. please contact me. I'll "pass
along" anything that appears to be out of my realm.
PHOTORESISTOR: 22 OHM light 2 MegOhm dark (All Electronics #PRE-13) or 30 OHM light 10 MegOhm dark (Hosfelt 24-136) or: most in Radio Shack variety pack work
Housing: Opaque tubing 1/4" !.D. (3/8" O.D.) #4400.05 (Organ Supply Industries) or: Cap from cheap black Paper Mate pen. Cap is 37mm long
Miscellaneous: 5 Minute Epoxy, wire sleeves, wire, Electrical tape: The shiny black type Paint: Fast drying black
The lamp is a tiny lamp that has just about the identical light output as the large lamp in the original Schober LDR and the same current consumption. The output was measured with a special lightmeter designed for that purpose. The photoresistors work in a very similar manner to "good" ones in the Schober 04LDR-1.
1) Solder about 11/2" of very thin wire to each of the pins of the lamp.
2) Place a 1" sleeve over each (or at least one) of these wires.
3) Cut a strip of electrical tape to 1/4 inch width.
4) Wrap this thin strip around the white base of the lamp until it becomes just thick enough to fit into the tubing (or pen cap from the large opening side). You will have created about a 1/16" cup at the end of the lamp. 5) Make sure that the sleeve is pushed all the way towards the bulb and place a tiny bit of 5 Minute epoxy into this cup. This will hold the sleeves in place.
2) Fill the space behind the photoresistor with 5 Minute Epoxy. Let it harden.
3) Push the prepared lamp into the opposite end of the tubing until it meets the photoresistor. (This places the filament of the lamp just about the same distance from the photoresistor as in the Schober version which had a rather large lamp).
4) Fill the space behind the lamp with 5 minute epoxy.
5) Paint the epoxy behind the photoresistor with black paint. (Light hitting the rear of the photoresistor, even through the epoxy can make a difference in its resistance).
If you use the pen cap:
1) Cut the pocket clip off the cap.
2) Cut 10 mm off the narrow end of the cap.
3) Push the photoresistor, wires first, through the larger opening of the cap. It will only go in until it is about 7mm from the narrow end.
4) Bend one wire to the right, the other to the left. This will secure the photoresistor.
5) Continue with steps 2 through 5 of INSTALLING THE PHOTORISISTOR AND LAMP above.
I have made quite a few LDR's this way. They work just fine for me. I spoke to Warren Boehling who designed much of the later Schober Organs. He told me that the light to resistance values of the Schober LDR's were "all over the place". They are not critical. I think that hot glue might be used instead of epoxy. To increase resistance for a given light output, put a small space between lamp and photoresistor.
If you have questions or want specifics, call me at 802 874-4894 or email me at Kruedener@Juno.com.
I found that the lamps in the Schober LDR's are usually good and it
is the photoresistors of the early times of solid state technology that
have failed, these LDR's can be FIXED. Next time I will describe
how to fix Schober LDR's.
The organ consists of two Devtronix generator keyers, one three manual and pedal generator/diode keyer, Schober generator for percussion which I use for a poor mans wood bar harp (That's the chrysoglott with a very short sustain). I am using Devtronix voice filters to accommodate the need for level adjustability and stop control from + 15 volts. Some of the voices are the Schober filter circuits on Devtronix cards. I have seven Devtronix tremolo/vibrato generators, nine audio output channels, 600+ watts of amplifier power, two digital delays which take the place of the Reverbatape which I wore out.
Speakers include two Leslies for Tibia and Vox Humana voices and separate systems for strings, pedal/tuba, solo, main, posthorn, bass octaves of tibia and synth outputs. Couplers include solo to great pizzicato ala Wurlitzer and there is a great manual crescendo. The pipe ranks are: Tibia clausa, consisting of a few Wurlitzer pipes among some home modified others.
Vox Humana, Wurlitzer
Harmonic flute, Unknown brand
Open Diapason, Unknown brand
Violin, tuned celeste to the electronic strings.
Open the Pearly Gates Lord,
The Legend is coming through
A little wider than usual please,
There's a Wurlitzer coming, too!
He used his talent well,
He really did you proud.
He used it to the fullest,
And always pleased the crowd.
A little child was born last night!
Give him the talent too, "You Know!"
The one you gave George Wright
To shine above the few.
He'll use it very wisely,
And practice from the start,
Just the way George did,
He played it from the heart.
We are sad to lose the Legend
With talent by the ton,
But now The Song Has Ended,
The Melody Lingers On.
Maureen Cross, Bendigo Theatre Organ
Society, Bendigo, Victoria, Australia