From: chuck adams (firstname.lastname@example.org)
I am looking for the above chip, a National LM703N.
Usual noise bridges as found in the ARRL Handbooks for
years have been using a Zener with 555 chip to generate
noise. Well, this years new ARRL Handbook for 1996 has
a new circuit that has reduced the parts count significantly.
This is good news. Bad news is that I can't find anyone that
has the chip.
So with all the experimenters in this group, surely someone
knows about this critter. Did they make it up? I don't
think so and hopefully it is not an obsolete part.
Any help greatly appreciated.
BTW: This new bridge, if you throw out the variable and do
it just for 50ohms reduces to the following parts:
1 - Zener
3 - Resistors
3 - Capacitors
+1 more resistor that I missed in my drawing
1 - Toroid
1 - Chip.
-- Chuck Adams (K5FO CP-60) email@example.com Box 181150, Dallas, TX 75218-8150
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