[BC] Part 15 radio station

[R A Meuser]

If you want to legally improve a part 15 transmitter, look at the 
antenna and the matching system. Most power is lost there and only a few 
microwatts are actually radiated. You may not get the boost that an 
illegal ground offers but I believe that with enough out of the box 
thinking a much better transmitter can be designed. Also, I see nothing 
in the rules that prevent synchronized networks. The Rangemaster has 
this capability.


Tom wrote:
> Try this one -
> 
> A fully compliant ground-mounted 100 mw TX with the 9-foot whip... and a 
> *buried* quarter-wave ground radial system... the whole 120 radials 
> thing.  Which, being buried, becomes the GROUND, not the ground lead... 
> which is that piece of 2" copper strap sticking up.
> 
> Next, add, at roughly a half-wave out, a roughly quarter-wave-tall tower 
> - NOT CONNECTED IN ANY WAY to the part 15 TX.
> 
> I tried this with a NEC-2/miniNEC model.
> 
> Not sure I believe the results... especially with that second, unfed, 
> totally unrelated, tower...
> 
> Can you say "virtual J-Pole"?  Is what it looks like, sorta....  Had a 
> LOT of gain, and came out virtually perfect omni.....
> 
> Richard Fry wrote:
> 
>>> How about if the thing is simply bolted to the top of a tower with no 
>>> ground wire at all?
>>
>>
>> If the tower is grounded at its base, then the tower _is_ the ground 
>> lead/wire.  If it isn't, the tower still is one arm of a dipole.  
>> Either way the tower itself will radiate, unless the Pt 15 tx is 
>> insulated from the tower.  Even then, the program and power wires 
>> leading away from the tx will radiate unless they are decoupled for r-f.
>>
>>> I can picture one of those things on top of a 2,000' tower.  
>>> Coverage, I'll bet!
>>
>>
>> The elevation pattern of a vertical monopole of more than 5/8 
>> wavelength wouldn't be optimum for producing groundwaves.