PL84 triode

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The PL84 pentode is very well known out there. I’m not going to write about it as there is plenty of information about the use of this pentode in push-pull amps, etc as well as comparisons with the EL84, EL86 and Russian equivalents such as 6P14P, 6P15P and 6P43P. I recommend you to check Klau’s work here.

I have a nice set of Telefunken PL84 which I may be using in triode mode as part of a Spud project I’ve been working on the design for some time. I’m interested in triode-strapped curves but also will be looking at tracing the Schade-feedback curves when I get the time to do so.

I quickly found a sample valve that was close to the pentode specs at 90%. Good enough for my purpose so I proceed to trace the triode curves quickly in uTracer.

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LME49830 Amp starts!

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Oh yes, a lot of sand! My good friend Tom recommended me to build this amp instead of an F5. Objective is to get baby-proof in 6 months. All HT valves will be removed unfortunately :(

300B will be built for a separate room….


Testing the MOSFET rectifier board!


LME boards just need the MOSFETs and are ready to go!