Once more, Google does the business! I typed in ‘precision series e-400 sweep generator’ and within minutes I found several really useful links.

There‘s a few photo’s up on my Flickr account, but here's one for starters.

Sweep Generator Innards

Originally uploaded by steamshift.

So on to the good stuff…

Technorati Tags:
hardware, technology, vintage, electronics

First up general information from www.radiomuseum.org:

Sweep Signal Generator E-400 (E400) Radio Precision Apparatus

Country:

United States of America (USA)

Year:

1948

Manufacturer/Brand:

Precision Apparatus Co. Inc.; NY

Type:

Radio Repair Equipment

Model ID:

75856

Wave bands

Wave Bands in notes or not known yet.

Power type and voltage

Alternating Current supply (AC) / 110 Volt

Material

Metal case

Valves / Tubes

8: 6J6, 6C4, 6C4, 6J6, 6C4, 6J6, 6X5, 0C3

Notes:

Generator frequency 2-240 MHz, sweep frequency deviation 0-1 MHz and 0-15 MHz.

Great stuff. I now have confirmation that it was made in the US and runs on 110v - very useful (though I will need to figure out how much current it draws so I can get a sufficiently rated transformer). Also very useful to have the list of valves; on the site, there are links to data about each one, with alternatives.

Secondly, thanks to Paco - a page with links to loads of manuals to old electronics, I found this:

E-400: Manual for Precision E-400 Sweep Signal Generator. Compliments of an unknown contributor.

Awesome. It came down in djvu format which I've never heard of, but I was able to get an application to open it from here. A quick PDF export later (I love OS X!) and I have a really useful PDF manual of how to use the Sweep Signal Generator.

So, from the manual we have the following description:

The PRECISION Series E-400 Sweep Signal Generator is a wide range multi-purpose frequency modulated Signal Source specifically designed for alignment and service of television, F.M. and other high frequency type receivers and circuits.

Great. So now I've got in depth info, what can I do with the thing? For now, SteamSHIFT out.

(Thanks to Paco and Radiomuseum.org.)