Original MARCONI OSRAM

KTZ41 10E/153 A819

closely matched pair

Vacuum Pentodes
Vf=4V, If=1,5A 
 the tubes seem to be NOS unused or slightly used, very closely matched, high emission:

tested in conditions: f = 4V  Ua = Ug2 = 150V Ug1 = -1,5V
 tube 1 - Ia = 19mA

 tube 2 - Ia = 20mA
where 100% for the new tube is 18mA
the tube has British 7-Pin (old B7, M7A) base
you will get the tubes you can see at the pictures

price is for the pair (2 tubes)

I always send the tubes by priority registered mail with tracking number within hours after receiving payment

                                                                                                                Santic [feat. Vera Hall] – Trouble So Hard