What can I do with 3Q4 Pentode tubes?

[abmoggy]

Hello,

I just got my hands on a pile of these small Tung-Sol 3Q4 power pentode http://www.mif.pg.gda.pl/homepages/frank/sheets/127/3/3Q4.pdf and am wondering if I can build something out of them. They have a max power output of 250 mw so can I parallel (x3, x5, etc)them in a SE configuration a la http://www.tubecad.com/september99/page12.html or can I use them as output tubes for a headphone amp?

Any suggestions? Thanks!

 

[Mr. Triatic]

if you connect them into triodemode you can build a SRPP preamplifier..
http://home.swipnet.se/dice/srpp/triatic_srpp.JPG

 

[Yvesm]

if you connect them into triodemode you can build a SRPP preamplifier..
http://home.swipnet.se/dice/srpp/triatic_srpp.JPG

But you'll need 2 independent batteries for the heathers

As a tubed headphone amp, it is highly improbale you may work without an OPT.

Yves.