[R-390] LM117K Mod and other issues

[Masters Andy]

Good evening.  I am working through a R-390A that I
recently acquired on EBAY.  It is an EAC '67 series.

It came with the Kleronomos audio mod and provides
excellent audio, especially on AM.  It also has a pair
of diodes across TB103 Term 10/13 and a wire going
over to TB102/4.  The power supply has been changed
over to a pair of diodes with a 200 ohm dropping
resistor.  I have recapped the IF and AF sections and
changed out the "out of tolerance" 2.2K resistors in
the IF section. 

Tonight I added the Current regulator mod from ER
number 70, page 24 using a LM117K regulator.  I ended
up changing R2 from 4.3 ohms to 4 ohms to raise the
actual voltage measured at pin 2 of the 3TF7 socket. 
Initially, with 4.3 ohms, I measured about 10.2 volts.
With 4 ohms, I am measuring 12.1 volts.  How close to
12.6 vdc do I need to be on the BFO/VFO tubes? 
Everything seems quite happy at 12.1 vdc and I am
inclined to leave it there unless there is a good
reason not to do so. The voltage stays solid as a rock
with the AC input being varied from 105 to 128 VAC.

I plan to add the Lankford full wave bridge AM
detector next and I am also interested in adding the
two 1n4148's to pin 2 V506A and Pin 1 V509.  Does any
one out there know of a reason NOT to do both of these
mods?

Thanks, Dutch Masters NU5O

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