From: joe smith <piewag@yahoo.com> Save Address Block Sender
 Subject: Ramsey FM-100

 I have developed a simple but positive fix for the
 "Power On" reset problem
 that this kit has.  Basically as designed the FM-100
 has a very poor power
 on reset circuit (among other problems) and if you
 turn it off for less
 than 10 full seconds and then turn it back on, it will
 come up stupid.
 Funny display characters and all.  This happens all
 the time with power
 glitches too which are plentiful where I live.

 It turns out there is a pretty easy fix that appears
 fool proof and totally
 positive fix for the problem.  Not just an improvement
 like the diode
 across R5 thing which just minimizes the problem
 somewhat.

 Would anyone be interested in this mod?  You need the
 following:

 (1) 2N3906 transistor (or just about any pnp small
 transistor)
 (1) 4.7K resistor
 (1) 3.9K resistor

 (A) Remove R5 and C22 and discard.
 (B) Install the 4.7K resistor in place of C22 by
 standing the resistor on
 one end.
 (C) Install the base-collector junction of the 2N3906
 in the holes of R5 by
 carefully spreading the leads of the transistor.  The
 Base of the 2N3906
 goes into the top hole at R5 location (closest to D7).
  The collector goes
 in the bottom hole at R5 location.  The emitter lead
 is free at this time.
 (D) Connect one end of the 3.9K resistor in series
 with the free emitter
 lead of the 2N3906.
 (E) Connect the other end of the 3.9K Resistor to the
 +12V unregulated bus
 which is available at a "feethru" hole just below C56.
  The emitter and one
 end of the 3.9K are not connected to the Printed
 wiring board.

 The circuit functions by the simple fact that the
 transistor is turned off
 when the 3 terminal regulator supplying +5v is no
 longer turned on.  Thus
 the reset line which is held up by the collector of
 the added transistor
 drops when the 5V regulator goes out of regulation and
 the Reset rises only
 when there is an ample supply of power on the input
 side of this same 3
 terminal regulator.  When the 3 terminal regulator has
 power the transistor
 is turned on and pulls the reset line high but since
 the base of this
 transistor is tied to +5, the collector is thus
 clamped from going higher
 than the logic high.  The emitter current is what
 actually turns on the
 transistor and that is supplied by the +12v line.

 This reset circuit can be used with any 3 terminal
 regulator by altering
 the R values.  It makes a very positive and fast reset
 circuit for any
 system using a 3 terminal regulator for its power.

 I invented it years ago and have used in on many
 products successfully by changing the 2 Resistor
 values to suite the power and the load.