[Bill Hutchinson]

Here's the SS circuit I used for replacing a synchronous vibrator pack I described in another part of the Phorum. Pardon my hand drawn schematic.

[Image: http://i27.photobucket.com/albums/c170/p...brator.jpg]

A couple of notes - all resistors are 1/4W unless otherwise specified. The view of the socket is from the bottom (pin) side. I used a junked 6 pin tube for the connection. The use of D3 and D4 provide rectification across the transformer's secondary, and I incorporated it into the circuit, so as to create a 1:1 replacement of the original pack.

The original circuit was designed to run from 12V, but didn't provide enough voltage (about 100V DC under load) when using a 6V supply, so I changed R3 and R4 from 150 ohms to 75 ohms to create more base current on the transistors, and the end result was 170V.

The transistors were mounted on a sheet of aluminum, a spare Radio Shack project box cover, and I used an RS PC board to mount the remaining components, then seperated the two using PC standoffs.

I built this into a Zenith 6V27 farm radio, but I'm sure there are plenty of similar Philco radios that would benefit from replacing the vibrator pack with a SS unit.

Hope you enoy the circuit. Many thanks to Norm Leal for his assistance in this project.

Bill

[Bill Hutchinson]

I received a few emails about the schematic being cut off on one side. I resized it, and I hope it works better.

Bill

[planigan]

Bill, still missing part of the schematic. PL

[exray]

Right click to view image and you can see it all.

[Ron Ramirez]

That is the result of a setting I made in the phpBB setup, so that pictures can be no wider than 1000 pixels.

Know how some photos scroll way off to the right on the Antique Radio Forum, which of course makes the text scroll way off to the right as well? Like many of you, I do not care for that. So I chose to limit the width of pictures posted to the Phorum to eliminate the scrolling.

I suggest that if you use Photobucket or other hosting, that you post a smaller photo here then include a link to a larger one on Photobucket (or wherever your photos are hosted). This should solve the problems.

Or do what Exray said. ;)