Synapse modules range

RX low noise amplifier

• http://forums.synapse-wireless.com/showthread.php?t=495&highlight=w%2Fsma

All Synapse RF Engines have a Low Nosie Amplifier (LNA) which makes the receive sensitivity -102dBm regardless of antenna being used.

• -102 dBm = 6.3 mW

Inside FCC limits max antenna gain purchase

• http://search.digikey.com/us/en/products/S151AH-2450S/730-1005-ND/1628300

5 5dBi Whip antenna length:200mm, price $12

RP-SMA

• http://forums.synapse-wireless.com/showthread.php?t=1353&highlight=w%2Fsma

The RF100 and RF200 modules require a Reverse Polarity SMA (RP-SMA) 2.4 GHz antenna
The RF300 requires a RP-SMA 900 MHz antenna.

Antenna, Range, LOS, FCC

• http://forums.synapse-wireless.com/showthread.php?t=1480&highlight=w%2Fsma

Your range tests sound about right. Using the RF100 I get about 300m usable range with the recommended antenna along a flat LOS surface. 
Increasing the height the engine is  mounted at can increase this distance. Using antenna with higher gain can make a significant difference 
to distance. e.g. an 11dbi antenna gives me at least 1km LOS along the  ground or about 4 km hilltop to hilltop. 
Without looking it up, Synapse give part numbers in the hardware manual for up to 5dbi antenna that still allows you to use the 
FCC  certification they have gained ( again from memory ). I think the rule is every 3dbi increase gives you 2 x gain. 
With the RF200's I get lower link quality readings in portal but  actual results are marginally better and much better battery life. 
Still not sure how Synapse get their specs - presume they are not actually testing engine to engine communication  
due to the significant difference in real life performance, but may just be monitoring for RF activity using a spectrum analyzer

Output Power

Zero dBm equals one milliwatt

• http://forums.synapse-wireless.com/showthread.php?t=1753&highlight=range

• Chip-antenna RF200P81 +3.5 dBm or 2.24 mW

• RP-SMA connector RF200PD1 +15 dBm or 30 mW

• RF300 +20 dBm or 100 mW
• RF100 +20 dBm or 100 mW in forum
• RP-SMA connector RF100 PD6 +18 dBm or 60 mW in datasheet
• F-antenna RF100 PC6 +18 dBm or 60 mW in datasheet

• dbm_to_watt_conversion

LINK MARGIN

Link Margin is the difference of TX power - RX threshold-power, expressed in dBm

• RF200P81 103 dBm datasheet
• RF200PD1 118 dBm datasheet
• RF100PC6 120 dBm datasheet
• RF100PD6 120 dBm datasheet

F antenna orientation

• http://forums.synapse-wireless.com/showthread.php?t=68

It should be pointed out that other factors such as physical (especially metal) obstructions generally have a greater affect than antenna orientation 
in most applications. Be sure to follow the guidelines in the SNAP Hardware Technical Manual for keep-out area beneath the F antenna, 
and avoid metal pieces in enclosure where possible. 
But there is no substitute for actual testing of the proposed installation. 
Often we are surprised by very good performance under less than ideal packaging conditions.
As far as orientation goes, ideally all antennas will be oriented in the same direction. This avoids attenuation due to cross-polarization. 
The theoretical optimum orientation of the F antenna is with the "stem" pointed upward, as shown below.
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RF100 Freescale MC1319X

• http://forums.synapse-wireless.com/showthread.php?t=558&highlight=amplifier

Synapse RF Engines are based on the Freescale MC1319X radio.

• http://www.freescale.com/files/rf_if/doc/app_note/AN2902.pdf

• F antenna gain is 2 dBi

RF100 Purchase

• RF100PD6........................................................................................................RF100PC6

File:RF200PD6-1.jpg price $29.95 File:RF200PC6-1.jpg price $22.50

RP-SMA connector

details on RP-SMA connector in this page RP-SMA