[EMAIL PROTECTED] wrote: > > For Scott: > > With respect to using the GE MII mobile frame for repeater applications: > > 1. Can you say categorically that there is sufficient TX/RX shielding to > prevent any desense at any power level the conversion is capable of > operating?
At UHF-categorically yes, because both the MII and the Micor were avialable from the factory in full duplex versions for certain applications. > 2. When these converted mobiles operate with reduced TX power, what happens > to the output impedance of the TX? Is it still 50 ohms? If not, does this > affect the physical length of the half wave interconnect cables often > suggested > between the TX and an isolator and/or the cavities? It probably isn't exactly 50 ohms, but should be close. And the cables from the duplexer to the radio do NOT *REPEAT* NOT need to be an exact length. This again indicates an impedance mismatch in the duplexer and it should be retuned. (or a bad antenna/load) > 3. If the output of the TX is other than 50 ohms as a result of a power > level change, does it upset the adjustment of the downstream isolator that > has > been tuned by a tracking generator? No it should not. The load on the 3rd port of the isolator is still 50 ohms, so it should not be an issue. And I don't see the impedance of a good PA like an MII or Micor changing off of 50 ohms enough to matter. Other brands, who knows. -- Jim Barbour WD8CHL
