The BE19400013B is a direct solid-state replacement for the HP neon tube reference P/N 1940-0013.  The neon tube is no longer available.  The neon tube is going to fail causing the +100V supply and all others to overshoot during startup.  This is because the neon tube has a small amount of a radioactive material that causes the tube to fire at its final voltage.  When the radioactive material reaches its half-life the tube will fire at a much higher voltage as shown in the scope photograph.   This causes all of the voltages in the 141T to overshoot. This is because the supplies are a tracking regulator.  When the -12.6V overshoots to -15V it will trigger the over voltage crowbar in the HP8552 IF section blowing the two 1A fuses on the back of that unit.   The display will show a slight glow on the right of the screen but no trace.  My BE19400013B uses a TL431 programable Zener and a standard Zener to produce a refence voltage of 82.3V.  The standard Zener is necessary because the TL431 has a maximum voltage of 37V.  The board layout is as close the dimensions of the original neon tube as possible.  The photos include the new kit, the original neon tube, the original neon tube in the 141T, the overshoot of the -12.6V supply, the overshoot of the neon tube reference (20V per division and 20msec per division), the startup of the -12.6V with the BE19400013B, and the installed BE169400013B in the HP141T.