Ramsey Electronics FT146 - Manual (Page 18)

FT146 • 18
❒ 112. Install C2, 100 to 220 uf electrolytic capacitor. Be sure to observe
polarity - especially with this part since it is directly across the power supply
and if reversed, could overheat so fast, so much that it could explode!
❒ 113. Install D5, 1N4002 style black epoxy diode, observe correct orientation
of the banded end.
❒ 114. Install D2, 1N4148 style signal diode (glass body with black band).
Observe correct orientation of the banded end.
❒ 115. Locate the aluminum press on heat sink and slip it on to Q6.
❒ 116. Install the LED transmit
indicator, LED1. Correctly identify the
cathode side lead which is the
shorter of the two. The shorter lead
goes into the hole nearest R13.
Install the LED, leaving full lead length extending above the board so that
the LED can be positioned later into the front panel indicator hole.
❒ 117. Install a wire jumper between points A and C on the PC board. This
allows the use of an Icom/Yaesu/Radio Shack microphone plugged into
jack J2.
This completes our assembly of the FT146 two meter FM transmitter. Now's a
good time to give your masterpiece a good going over, being especially alert for
any:
•
bridged over solder joints,
•
misplaced components,
•
transistors or diodes placed incorrectly,
•
electrolytic capacitors installed incorrectly.
TESTING, ALIGNMENT AND ADJUSTMENT
To prepare your FT146 for testing, you'll need the following items:
❒ 1. A suitable microphone of the Icom, Yaesu or Radio Shack variety.
Other microphones may be used providing you mate them correctly to the
FT146. Since there are such a wide variety of microphone types and styles,
we cannot provide exact hook-up wiring for every case. Hook-up is very
simple, follow the basic instructions in the "Microphone Considerations"
section.
❒ 2. A hexagonal, non-metallic alignment tool. If you do not already have a
set of plastic or nylon coil alignment tools and do expect to build more ham
radio or electronic hobby projects, such tools are worth having and can be
found inexpensively at any electronics store including Radio Shack. While a
metal Hex key wrench will fit the coil slug, the metal itself will detune the
R13
Short lead here
Leave leads long