Tag: Derk Reefman model

6P15P triode strapped models

I’ve been playing lately with the 6P15P. Also I have developed several spice models of these Russian clones which I will be publishing shortly when I get the time to do the proper write up.

I use Dmitry’s Paint_kit tool a lot. It’s very good and accurate once you learn how to use it. It’s not easy to match triodes first time as many variables are in play. After working with Derk Reefman on the pentode models, I noticed a slight divergence on his triode models. Derk suggested that the best was to use the triode-strapped pentode for this. Here is a simple comparison between Dmitry’s model and Derk’s:

6P15P triode model comparsion
Derk and Dmitry’s models under test

 

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6P21S tetrode curves and model

6P21STime ago I generated the tetrode curves for this great directly heated tetrode using my analog curve tracer. I originally used this tetrode in triode-mode. Although it’s a good candidate for a SET amplifier with its 21W in triode-mode, I always wanted to find out how it will perform with Schade-type anode to grid feedback. Building an accurate beam-type tetrode model was key. Luckily now, Derk Reefman has developed an accurate model for these type of valves.

I also worked with Ronald Dekker and insisted him to build in the “Schade” feedback capability in the uTracer using software rather than hardware:

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