Archive for March, 2009

Lazarus – Eico AF-4

Sunday, March 1st, 2009

I’d been wanting to try out a single ended amp for some time, though I wasn’t really looking for a project.

I purchased this Eico AF-4 on that auction site, and was horrified to find a tremendous amount of corrosion, an amputated output transformer replaced with a dodgy lookin substitute, and a general state of advanced decrepitude. The power transformer tested OK and the case, faceplate and all the knobs were there, so I decided to let the less-than-up-front seller slide and put it on the shelf.

I kept seeing and and wishing I had the cojones to dive into it. It was a kit originally and I had the build docs.  Fortunately I had the good sense to put this project into the hads of my good friend Russ, a professional electronic technician and all around handy guy.

Heyboer Transformers was kind enough to wind me up a pair of OPTs to the original specifications, and the kind folks at Triode Electronics scrouged the full BOM from the build manual, which the Eico User’s Group has in it’s file library.

Russ stripped the chassis and allowed me to try to save the metal bits. I got the rust off and some paint on and he took over.  Everything except the controls and power transformer are being replaced with modern high quality components as everything was pretty corroded. Some initial mods planned were to replace the proprietary speaker connectors and vintage inputs. The ceramic phono input is being change to line level and the power connector on the back is being eliminated. 

Once it’s up and running we’ll evaluate how it’s running and contemplate further tweaks.

The pics will be posted here as Lazarus rises from the grave.