In the last century I bought a few thousand tubes and tested them with the computerized curve tracer Sofia by Audiomatica. The tubes I purchased were mostly direct heated triodes ( DHT ) and high transconductance noval. Over time I have kept only the most linear tubes and matched them. In the coming weeks a part of my collection will be on sale (among these DHTs such as UX201A, CX301A, 171A, 112A, CV1660, 3A/110A, AC/P4, 801A, 10Y, 801 RCA ceramic base, RE604 TFK globe, RE084, RE134, D3A Siemens, etc )

If you need information on the interpretation of the curves or enlargements of specific areas, just ask

Auction for one  pair of Cornell Dubilier paper in oil capacitors 4uf 1000vdc  used and tested 

For any infos and for combined shipping, please ask. For shipping outside Europe, please ask for better prices