DAP25
•
9
to provide additional gain for the antenna. The 9 VDC power to run the
amplifier is “piggy-backed” up the RF cable and is decoupled at the antenna
circuit board. There is also an additional protection diode on the amplifier input
to prevent any damage to the sensitive IC.
Ramsey offers two models of this particular antenna, one with no active
components and the other with a low noise preamplifier to further boost the
antenna gain.
The DAP25 kit which your are about to assemble is the preamplified version.
The advantages to this particular model are that in addition to the gain and
performance of a standard discone antenna, the DAP25 offers an additional
low noise amplifier to provide higher gain for reception of weak signals.
However, if your particular application is for transmission of signals, this is not
the kit for you. The low noise amplifier could be damaged by injecting RF
power into the antenna. We recommend the non-preamplified version of this
kit, the DA25, for transmitting applications. The good news is if you have not
begun assembly yet, you may return your kit for full credit towards the non-
amplified version within 10 business days from original purchase.
PARTS SUPPLIED WITH YOUR DAP25 KIT
1 3 Qt. funnel “cone”
1 7 inch pie-plate (
CAUTION, EDGES MAY BE SHARP!
)
3 #6 – 32 x 1/4” screws (Nylon)
3 #6 – 32 M-F stand-offs (Nylon)
3 #6 – 32 nuts (Nylon)
1 DCA1 circuit board
1 PVC coupling
1 3” buss wire
1 3’ length type “F” to jumper cable
1 Feed thru power inserter with wall plug transformer
SURFACE MOUNT COMPONENTS: Note there are extra chip capacitors and
resistors included (They’re real small aren’t they!).
3 220 ohm surface mount resistors (marked 221) [R1-3]
2 .001 uF surface mount capacitors (Gray smt package or marked A3)
[C1,2]
1 33 nH surface mount inductor (White smt package or marked R33)
[L1]
1 BAV99 dual diode (three tabs marked 7X ) [D1]
1 MMIC amplifier (four solder tabs marked 5) [U1]
