Thanks for the timely reply.  My experience s that I most vividly recall with the Philbrick equipment was with what we called the "Philbrick manifolds."  These were the 300VDC units with the octal base plug-ins.  I forget how may sockets were available per unit. I know that we ended up using two sockets per amplifier since we typically used a chopper stabilizer/amplifier combination for low drift and high gain.

We basically used the manifolds for small analog computer set-ups in our test cells where we would simulate simple hydro-mechanical control schemes with the Philbrick. It was extremely useful and very versitile.  I remember that we also had two large L3GED's that I did a lot of simulation work with.  They had 24 100 VDC op amps and these two prong, plug-in, variable resistors that looked like distillation columns.  When you had it all wired up it really did look like a model refinery.  If anyone ever took one wire off you were as good as dead.  But my favorite was the Philbrick.  I could take it anywhere, set it up and get running quickly.

Young engineers today don't know the fun they are missing when they never have the chance to work with analog computers. By-the-way, I remember Dan Shinegold so very well. I never met him face-to-face but talked to him countless times on the phone when I was trying to work out some difficult problem. A true gentleman and consummate professional!

Thanks again



At 04:11 PM 3/17/2006, you wrote:

Hello Chuck, nice to hear from you. Your interest is a great incentive to keep the site up.

I do have the Palimpsest mentioned in the "recommended reading" section, but given how important this is and that you did not see it on first inspection, I am going to bring mention of it to the front page at the top of the applications section.

I would love to hear anything that you might like share about using Philbrick or similar products. If you remember an application, that would be of great interest to other Philbrick enthusiasts, as I have very little material covering actual applications.

Recently, I have been making some gain measurements on the SK2-V amplifier, and I have posted the in the measurements section. I have been discussing these with Bob Pease, who was the production engineer for the SK2-V, and helped refine the design. I am also trying to design my own 2 tube opamp, so check the site occasionally for the latest.

Best regards,

-Joe Sousa


Joe Sousa,

I just found your site and it brought back so many memories.  I was wondering why there was no mention of the GAP Palimpsest.  I remember using that as almost a bible when I was starting off as a young green engineer at GE's Lynn Mass River Works in 1957. I thought it was so interesting and well written. 

"Thanks for the memories"

Chuck Maher