[Boatanchors] Urm / 25 J sig gen

[pete williams]

G'day  list..
 A minor technical topic... i  don't know if it's worth much to the
users,  but a  recently  bought  URM- 25 J appears to have a   small
improvement - seemingly sanctioned by whomever in that the  oscillator
heater has been  regulated.
Not the same as the   "G"  version tho' . The   heater winding on the
xfmr @ 6,3 V now has an auxilliary board with a   couple of diodes. a
pair of caps and a   zener 6.0 v plus a 7,5  ohm  resistor... All this
goes to make up a   regulated  voltage doubler.
 Whether it makes any improvement in stability has to be proved..... I
only mention all this as the notes on the  URM -25 list seem to be
silent on this  score.

 ARC-38 A.... hf  xcvr... If I ever get  to solving autopositioner and
associated  SMO problems  with this  box. I'll be the  only one in
captivity with the solutions--------  seems noone else, despite
pleadings,  has or is willing to pass on  historicals ---.
research continues. ! !

.
Pete Williams
jupeter at supernerd.com.au
METUNG

Pete