Multicoupler QuestionS

[dimab]

1. What is the difference between active and passive couplers?
I saw a price difference of 200% for active vs. passive from STRIDSBERG
2. Can a STRIDSBERG multicoupler handle transmission from a ham to the antenna?
3. Is there a multicoupler that will enable me to share a single TX antenna that will do RX functions and TX functions? (specifically the Austion Spectra, which is what i have for scanning right now, and is able to TX)

Any links to products and explanations why or why not's are greatly appreciated.

 

[wa8vzq]

1. An active multicoupler has an amplifier that makes up for the loss associated with distributing the received siganl between serveral receivers. For the sake of argument and neglecting other losses, a passive 2 port multicoupler splits a single antenna into two receiver ports. The signal level at each port is 3 dB lower than the signal at the antenna. An amplified multicoupler would have 3 dB gain so that the signal level at each port equals the signal level at the antenna.
2. Multicouplers are one-way devices designed and are not intended to handle transmitted signals.
3. Not to my knowledge - when you begin adding transmitters into the mess, the situation becomes very complex. Multiple transmitters can share a single antenna using diplexing techniques - usually cavity filters and at some frequencies also using feritte circulators. Each cavity and circulator is adjusted for a specific frequency. They can be configured to transmit and receive BUT only on the one frequency. This essentially how a repeater operates. A single transmitter and a single receiver are diplexed together to share the same antenna.

Dan
Apple Valley, MN

 

[dimab]

so much for not having an antenna farm :-\