-----Original Message-----
From: Alfred Lorona <alforo@megsinet.net>
>
>Can anyone tell me how the plus voltage for an electret mic on pin 4 of the
>front panel mic connector is derived? Series resistor? What value? I have
>been unable to find the connector on any of the schematic diagrams in the
>manual.
>
>73, AL e-mail alforo@megsinet.net
>
Hi, Al.
At this time of morning and my age of life, a magnifying glass is very
helpful--actually, probably helpful at any age when dealing with 8.5x11
schematics. I've also found different colored highlighters to be very
effective in tracing the circuit of interest--If I looked for it once, I'll
likely look for it again!
Check the Main Wiring drawing (in my manual, it's just before page 5-1--a
fold-out page,
but not the Logic Board).
The mic jack is at the upper left corner.
The PTT and +Mic leads run together down and across to the 81596 board to
connector 65. The Control Board (81596) schematic shows the PTT/+Mic connector
65 at the top center of the drawing. There you will find how the voltage is
derived: from the +Reg (connector 59) through R39, a 470 ohm resistor.
73,
dale, kg5u
--
FAQ on WWW: http://www.contesting.com/tentecfaq.htm
Submissions: tentec@contesting.com
Administrative requests: tentec-REQUEST@contesting.com
Problems: owner-tentec@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|