Redesigned X-10 LM465 Lamp Module.

[Charles Sullivan <cwsulliv@xxxxxxxxxxxx>]

A major redesign by X-10 of the LM465 plug-in Lamp Module hardware
and firmware occurred around the beginning of 2007, with radical
changes in characteristics.  Unfortunately however the model desig-
nation was not changed from LM465, which will undoubtedly result in
a lot of user confusion.

A comparison of the characteristics of the original and redesigned
LM465 based on my testing can be found at
  <http://www.heyu.org/docs/New_LM465.txt>
and is reproduced below.

Any additions or corrections will be appreciated. (My email address
is good.)

Regards,
Charles Sullivan
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       COMPARISON OF NEW VERSUS OLD LM465 LAMP MODULES
                by Charles W. Sullivan
                    22 July 2007

A major redesign by X-10 of the LM465 plug-in Lamp Module hardware and
firmware occurred around the beginning of 2007.  Unfortunately however
the model designation was not changed from LM465, which will undoubt-
edly result in a lot of user confusion.

This note will attempt to describe the major characteristics of the
new design as compared with the original design. This information was
obtained by trial and error measurements on actual units, as X-10 has
published nothing about the new design other than a short note in
their knowledge-base wiki (http://kbase.x10.com) indicating it has a
"Soft-Start" feature.  The units tested here all have date code
sticker 07D17.

The characteristics of the original design LM465 (and rebranded units
sold under the RCA, IBM, and Radio Shack labels) remained basically
unchanged over the years from those of the original BSR units (brown
housing with side thumbwheels).  The module responds to X10 signals
All_Units_Off, All_Lights_On, On, Off, Dim, and Bright.  Alone among
dimmer modules manufactured by X-10 and others, it does not support
the All_Lights_Off function.

If an original-design module is in the Off state, a received Dim
signal will first bring it to full brightness before dimming.  The
only way to avoid this is never to turn the module Off but instead
to dim it to minimum brightness (which is usually visibly indistin-
guishable from darkness).  Then it can be brightened as desired from
that point.

The new design shares many characteristics with the discontinued
LM14A 2-way Lamp Module although it remains a 1-way module, i.e., with
no status-reporting capability.  However it now supports the Extended
Code Preset function which allows it to be directly set to any arbi-
trary brightness level 0-63.  In common with the LM14A it now supports
the All_Lights_Off function.  Also in common with the LM14A, minimum
brightness (at extended code preset level 1) is nowhere near darkness,
but about at the level of 15% of line voltage.  However this is not a
critical limitation now that the module supports the extended code
preset function.  It is fully Off when turned Off (at extended code
preset level 0) by either an Off command or by an Extended Code Preset
command.  The new design also supports the Extended Code All_Units_On
and All_Units_Off functions.

The new design has a "resume" feature similar to the LM14A, i.e., the
ability of returning from Off to the previously set brightness level.
However this feature is not called into play when the module receives
an On signal but when it receives a Dim signal. The dimming continues
from that point, so to repeatedly turn Off and then resume the exact
same level, it is necessary to follow the Dim signal with a Bright
signal of the same magnitude.  If the new design receives an On signal
when Off, it ramps up gradually over about two seconds, but to full
brightness regardless of the previous level.

More details about the characteristics of the new design LM465 will
undoubtedly reveal themselves with time.

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