Schober Organ Notes No. 59
Disclaimer: We accept no responsibility for any unfavorable consequences
resulting from following our advice
This is the first opportunity to wish all of you a Happy New Year; so,
HAPPY NEW YEAR!
It seems that we all survived Y2K, the biggest nonevent ever. I have to
admit that in the last day or so before December 31, 1999, I did make sure
that I had a week's worth of groceries in the house and I filled a few
vessels with water. Fortunately it was in vain. Now the flu is a real concern.
I sure hope that all of you are well and if you did catch it, that you
got over it without suffering too much.
In ON 58 I asked if there was any interest in getting the "puff of air"
preset systems to work again. There was a positive response, so when I
made a trip to Vermont I picked up the materials I had bought previously
to try and make the little air bags that operate the stop switches. I will
have something about either success or failure in ON 60. ak
Bob Bainbridge and his Fabulous Robertone MK-8 was the "portrait" article
in ON 53. The electronic chimes he designed for this organ were briefly
mentioned in that article. Here is a little more about them.
The unit is designed around a Top Octave Divider (TOG), in this case
a 50240 IC. These were common and cheap-Schober used them in their IC Tone
Generator. They are still available, but not so cheaply, from Keyboard
Systems. This entire chime, though, could be built quite inexpensively.
Bob used a 4001 IC and a 2MHz crystal as a master oscillator. He fed the
output from this to the 50240 TOG. Then each tone from octave 8 (except
the second or higher C) is fed to one of twelve 4024 IC's and divided into
seven more octaves. So, octave 1-7 is available from the outputs of the
4024 IC's. Octaves 3, 4, 5, 6 and 7 are used in Bob's design. A combination
of four of these tones makes a "chime" sound. For example, for a C5 chime,
the following notes are used: C5 the fundamental, E4 hum tone, G5 fifth
above fundamental, C6 overtone. These four tones have to be switched, and
Bob uses 1N4184 diodes for switching. The four tones are then combined
in a TLO84 IC mixer amplifier/shaper. The output is fed to a 3340 IC amplifier,
which is also used as an on/off switch, via a stop tab. (See partial schematic,
Bob has 15 pages of charts and schematics, some only pertinent to his organ,
that I will be glad to send you for a SASE with 55¢ postage, plus
two loose 33¢ stamps. If you have some electronic knowledge, you will
be able to figure things out and build this chime. I have a recording of
Bob's Robertone MK-8 and the chimes (as well as the rest of the organ)
sound just great.
There have been many problems with the Recital pedal clavier. Broken flat
springs on the original (non-kit) pedal clavier lead to solutions using
elastic bands and loops. This is OK for a while, I guess, but not ideal.
Schober came up with a fix and had an Information Bulletin, BN-039, which
describes a way of attaching expansion coil springs and removing the old
flat springs (both at the switch end) of the clavier. Philip Becker, one
of our members, came up with a great method of strengthening the clavier
and adding new flat springs at the other end of each pedal with a tension
adjustment. I can send you a copy of both if you send me a 33¢ SASE
plus one loose 33¢ stamp. ak
Member Captain David Casteel sent me several Information Bulletins (including
BN-39 above). Amongst them, as well as other interesting ideas, are the
schematics and wiring instructions for five new voice filters for the Schober
Library of Stops, both reproduced on page 4.
Because of space limitations, I had to use the speakers from my Stereo
system for my Schober organ as well. It is a no-no to parallel the outputs
of two amplifiers, so something had to be devised to switch the speakers
from the Stereo to the Schober and vice-versa. A manual switch would do,
but it's not particularly convenient. The circuit below automatically switches
the speakers from the Stereo to the organ when the organ is turned on.
Use two DPDT relays or one 4PDT for two speakers. ak
Member Alan McFarlane writes: "...It is sure a pleasure to play the organ
without a lot of missed notes and odd noises caused by poor key contacts.
That Pro-Gold spray works wonders and I hope every Schober owner gets a
can of that great stuff. When I think of all the times I removed those
keyboards and wiped down the gold busbars, I shudder. I always wondered
why they needed cleaning when gold is not supposed to corrode or tarnish.
Seems like in time the base metal actually migrates through the gold, according
to Caig Labs who make the stuff. Whatever the reason, I almost gave the
organ away once because of those %$#@ keyboards!" (See ON 57 and ON 58
for retailers that sell contact cleaning sprays).
SCHOBER RELATED ITEMS
A Consolette II, by Richard Thompson, 403 E. Smith, Bay City, MI 48706,
Tel: (517) 684-1076
An old style (single board) Percussion (PRCN-3/PRRN-3). Please contact
Alan McFarlane, 1609 S. 7th St., Aberdeen, SD 57401, Tel: (605) 225-2410,
A Lowrey LSA "Holiday" tube organ is available for $100, (pick up only)
from: George H. Goldstone, 1010 Burnham Rd., Bloomfield Hill, MI 48304
Tel: (248) 642-7673
Does anyone have a Schober suggested Registration List for a THEATRE voiced
Recital? A copy would be appreciated. Please send it to my NY address,
listed at the end of this newsletter. Alexander Kruedener
NON SCHOBER RELATED ITEMS
I found a place where hard to find Reel to Reel as well as cassette audio
and video tape is available at very low prices. Get a flyer from AUDIO
TAPES, INC. Tel: (703) 370-5555, or e-mail AMPEX641@aol.com.
SELL, TRADE OR GIVE AWAY
Nothing this time. Does anyone have anything for this section?
Please Address All Correspondence And SASE DONATIONS TO: ALEX KRUEDENER
Email: Kruedener@juno.com Winter Address: 161 E. 89th Street New York,
NY 10128 (212) 831-0662