[TenTec] Bulb replacement in Model 238 Tuner

[Dr. Gerald N. Johnson, electrical engineer]

The 1813 and 1892 are practically the same lamp. 14.40 volts at .1 or
.120 amps. I don't know but probably TenTec uses which ever one they
have handy at the time of assembly. If you want longer lamp life look
for a 28 volt lamp, like a 313, 757, 1864, 1818, 1820, or 1829. That's
an easier change than adding a resistor. Otherwise the original lamp
could have a series resistor or 68 to 150 ohms. 1 watt would be a
suitable power rating. Its hard to predict resistor power dissipation,
because the lamp resistance is so nonlinear.

73, Jerry, K0CQ
-- 
Entire content copyright Dr. Gerald N. Johnson. Reproduction by
permission only.