Ohio Scientific 4P computer, 
Has a 540 IO & Video and floppy board, 502 CPU board and Mem+ aftermarket memory board. This machine was heavily modified in the day for extra features and would have a 5-1/4 floppy not included.
I was told this computer worked when I purchased it over 10 years ago and have never powered it as I don't trust the old power supplies.  I always intended to work on it after I finished my 8P but that never happened.  I have too many projects right now and it needs a new home.
This is sold as-is for parts or repair.  
I charge for actual shipping only, the calculator is not very accurate and will over charge.  It may take more than 3 days to package this properly. 
Please ask any questions


On Dec-02-15 at 18:36:06 PST, seller added the following information:

Thanks to Dave's OSI repository 
Look for Peek65 Issue 04 1983 as Ebay will not allow me to include the link.  

The issue describes the Mem+ memory board, a review and ad.  The third photo shows it pretty well.