BAUSCH & LOMB INCORPORATE D

R o c H E i) T E R 2, N E- W Y Oo R K

ATR MAIL v May 16, 1961

The Standford University
Medical Center
Department of Genetics
Palo Alto, California

Attention: Dr. Joshua Lederberg
Prof. of Genetics
Subject: Spectronic 505
Reference: Your letter of April 27

Dear Dr. Lederberg:

I am happy to hear that your Spectronic 505 is now work-
ing properly and that trouble with the light source
and the hydrogen lamp no longer exists.

I have sent you under separate cover a service manual
for the Spectronic 505 which you requested. This con-
tains the wiring diagrams and circuits, along with the
complete instructions for servicing of this instrument.
We are making plans to have an engineer concerned with
the Spectronic 505 visit the West Coast in the near
future. Because there is no established time for

this visit presently set up, I wouldlike to get the
details concerning the equipment which you may require.
I would further like to say that we are finishing the
design of a time rate accessory for the Spectronic 505.
This accessorywill consist of a second pot in conjunction
with the linear potentiometer presently in the instrument.
A driving voltage will be taken off this second pot,
relative to the position of the pen on the Spectronic
505. This voltage can be sent into a stripchart re-
corder for long and consistent time rate recordings.

The output from the second pod will have two ranges,

one from 0 to 15 and the other from 0 to 115 millivolts.
Almost any external equipment or recorder capable of
accepting these ranges with a relatively high impedence
will be feasible.

The setup for light scattering studies often depends
on material involved and we would appreciate knowing
your applications and details of the materials to be used.

 
BAUSCH ~® LOMB INCORPORATED

TheStandford University May 16, 1961

It is possible that light scattering measurements can
be made with the reflectance attachment either before
or after the integrating sphere. Also, details con-

cerning the Densitometer for analysis of photographic
plates would be greatly appreciated by our engineers.

I suggest that you outline what equipment you would
want us to consult on or design for you.

Very truly yours,

RFFreitas:DC Product Supervisor
Analytical and Photogrammetric
Instruments Section