in time for holy week.....
another 2A3 set modification completed, tweaking goes on, but for now,
i am sure i will be able to put a smile on the owner's face...
driver tube used the TFH( tube from hell) we at diyadio codenamed to slow
down them you know who....
![Wink ;)](https://www.pinoydvd.com/Smileys/default/wink.gif)
the driver tube is a 12HL7, but 12GN7 and 12BY7 can also be used....
these are video pentodes wired as triode, their high transconductance accounts
for the high local open loop gains...
i am unable to challenge the JJ's past the 250volt 60mA operating point
due to limitations of the power traffo....
![](https://scontent.fmnl3-2.fna.fbcdn.net/hphotos-xaf1/v/t1.0-9/s851x315/1620475_1093246744030292_4564540087824532135_n.jpg?_nc_eui=ARj6GOXp6eAuveTSTjB3HAG9d3Mt7TlgTATR9o79Z66skqPIJUuFcIpgB3kF&oh=cba9735d2c6f354b07ca74d509ab6ae3&oe=578D1E45)
![](https://scontent.fmnl3-2.fna.fbcdn.net/hphotos-xfp1/v/t1.0-9/10593094_1093246797363620_8505959577886414789_n.jpg?_nc_eui=ARivLUjgo-V2HffDbMuQs0BQhwJAE8iXtM_Sz49_mvoY0I47li_xq0l9dqqV&oh=4140426947ae61c648638cf2edfc7077&oe=574D2948)
![](https://scontent.fmnl3-2.fna.fbcdn.net/hphotos-xaf1/v/t1.0-9/1620475_1093246744030292_4564540087824532135_n.jpg?_nc_eui=ARhFS-YuiMp9ZnOvlQonKoYn0GZk0f1cK6_Oy5w_QC-jgz3mN_kTFq9KJwX0&oh=0dbc4f12ca977ed058b31fdddec114ac&oe=57529A4C)