I dropped some button batteries at the dedicated shack at the dump, and there on the shelf was an old chassis, with two tubes, so I grabbed them. Mopers exa(?), Made in Holland, EL84_68QS5 (logo is a tube playing trumpet!) Gulbransen, Made in England, EX81/6CA4 (very classy typeface on brand name) Are them same tubes as typically found in guitar amps? Now that I think of it I shoulda looked at the chassis in detail... EDIT: Gulbransen made organs... maybe this is an amp project extracted out of an organ like we had on the forum a month ago?