View Single Post
Old 23rd Sep 2019, 12:00 pm   #27
Thyratron Valve
Thyratron Valve's Avatar
Join Date: Aug 2017
Location: Ipswich, Suffolk, UK.
Posts: 14
Default Re: Regentone A133 HT smoothing capacitors, V4 cathode resistor

Originally Posted by Herald1360 View Post
Sounds like the EL41 is getting tired. Another possibility (thinking UL41 DAC90A problems here)- have any of the unused pins on the valveholder (3,4,6) been used as tie points for wiring? If so, there may be some mileage in "floating" any such connections.

You can try reducing the grid resistor from 680k to ~330k to see if this helps a bit and just increase the cathode resistor to get the total current down to around 35mA. This will allow the valve to soldier on a while longer- probably for ever if the set is not used much!
Thanks for that I will check those pin connections, and will check the current and adjust resistors accordingly
Thyratron Valve is offline