> measures writes ...
>
> ? A rheostat to adj. fil/heater potential costs under five dollars
> wholesale. Do any MFJ-Ameritron amps have one? Would people pay a bit
> extra for such a feature?
>
To be effective the filament rheostat would require built-in metering
with proper RF decoupling at considerably more cost or would encourage
semi-trained appliance operators to operate their amplifiers in a very
unsafe manner (covers off, power on) in order to set the filament
voltage properly.
If you were a commercial amplifier manufacturer, with considerably more
to lose than a bit of wire an a few resistors, what would you do ...
build an amplifier that might require the user to replace tubes a
couple times in 20 years of amateur operation or potentially cost the
user his life and subject the company to a multi-million dollar
wrongful death/product liability lawsuit?
A user with sufficient technical knowledge and concern over filament
voltage issues should be able to easily add the proper rheostat or
filament dropping resistor. Such a user can probably do it safely
as well, unlike the legion of snake oil buyers.
73,
... Joe Subich, W8IK
<W8IK@Subich.com>
<www.qsl.net/W8IK>
--
FAQ on WWW: http://www.contesting.com/ampsfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|