26-08-2020, 07:19 AM
I doubt the valves are faulty, they are very reliable and I've only had failures due to my own mistakes.
I've had gains up to over 100mhz on the 1J24B and the 1J18B. Even the 1J42A can be useful up to at least 20mhz
Try reducing the G2 feed resistor, make sure your method of construction isn't lossy and screen the valves too even tin foil wrapped around the valves and grounded does for experimental work.
I use a sheet of copper laminate board and use the manhatten method as its the best for RF
I've had gains up to over 100mhz on the 1J24B and the 1J18B. Even the 1J42A can be useful up to at least 20mhz
Try reducing the G2 feed resistor, make sure your method of construction isn't lossy and screen the valves too even tin foil wrapped around the valves and grounded does for experimental work.
I use a sheet of copper laminate board and use the manhatten method as its the best for RF
