Hi Dave, I know that the Sirio 5000 has a UHF mount. I tuned mine from 26.950 (1:7) - 28.740 (1:7-1:8) on MFJ-259. I read a post on a forum where someone tuned his to do 10, 11, and 12 meters after hard mounting it to body.
I read a post on a forum where someone tuned his to do 10, 11, and 12 meters after hard mounting it to body.
Hard mounting doesn't give you more bandwidth, it just alters the resonant point of the antenna. 5MHz with a SWR low enough to be usable is a big ask for any antenna.
The problem you have with radio is there's a wide range of what some people will find acceptable. For that person it could be that the SWR meter needle only went into the red a little. There's also a lot of variables that can come into play and what he sees as a good thing, wide bandwidth, could actually be an indication of a problem.
SWR is also a whole lot more than the X:Y ratio. Its the Resistance and Reactance and you can still have low SWR whilst having some really bad R or X values.
So far so good...
Can you give me an example of X and/or R being no where near expected values and still having a low SWR assuming the RF source and the feedline both have a characteristic impedance of 50 ohms?
The DB
I didn't say expected values, just less than ideal. Its possible to get a 1:1 SWR with a bit of shunt matching for an antenna with an unmatched R in single digits for example. Its going to be a really shitty antenna but has a 1:1 SWR so its good, right?
Hard mounting doesn't give you more bandwidth, it just alters the resonant point of the antenna. 5MHz with a SWR low enough to be usable is a big ask for any antenna.
The problem you have with radio is there's a wide range of what some people will find acceptable. For that person it could be that the SWR meter needle only went into the red a little. There's also a lot of variables that can come into play and what he sees as a good thing, wide bandwidth, could actually be an indication of a problem.
SWR is also a whole lot more than the X:Y ratio. Its the Resistance and Reactance and you can still have low SWR whilst having some really bad R or X values.