Protelgram 3NP4 + optics

[bandersen]

Originally Posted by Dave A

...using the Protelgram system. The optics are so touchy to set! And the focus is critical. You can focus on the front or the back of the plastic fresnel lens and it will actually tint the picture if you are on the wrong side. And it is only about 1/16th inch thick. Those physics of light are beyond me.

And there are some oil-filled electrolytics! Be carefull. I am suspect as to what the oil is.

This set is a 630 jeeped up with Jones connectors to guide the video to the Protelgram unit.

Impressive! What do you think of the picture when everything is just right ?

[pearsonk]

The oil filled part is the HV trippler. It is used to keep the tubes
cool I think. I have rebuilt one, forgot the tube #, they are wired in. refilled with mineral oil.
Dave's picture is very good for one of these, especially in the bright light.
The concave mirrors cost me about $80 to resilver............