70MHz 4CX250B Amplifier GW4RWR

It had been twenty years since I build a tetrode amp. I found three of these valves literally rolling around in my carboard junk box, and wondered whether they still worked. So it was a 4m amp for the 2013 summer project - not that I need another amp for this band, this was just to pass time.
In keeping with my liking for all things 19", this amp was built into a 3U cabinet, with blower on the rear panel.
Anode circuitry is a simple pi network, using 5mm dia solid copper for the L. Grid volts wouldn't drop much below -100V due to my transformer's 70V secondary, so I've had to ensure that the screen is grounded on receive.
Front panel switching is for blower and the screen/grid/switching transformers. Meters for screen current with zero offset, and power out. LEDs for TX and Grid current. Rear panel is fitted with N types to accommodate a CX-520 relay, and more N types to feed drive in and Rx out. Phonos for PTT in, DC out to power the CX520 and one spare socket. HV goes in on C-type.

Results
With 2.2kV on the anode, a few watts of drive drive gives an easy 200W out.

Conclusion
These days most people would use a FET for this power level. But why not remember how it was done during the 'good old days'?