On Fri, 03 Oct 2003 01:17:32 GMT, James Knott <bit_bucket@rogers.com>
wrote:

>Liam Ness wrote:
>
>> I'd be very interested in what you are basing your statement that it
>> would be illegal to use a 3 watt range rf amp. There definately are
>> regulations on how much power you can transmit on at the cellular
>> frequencies, but I believe 3 watts is alright as it has been done in
>> the past by the cell phone manufacters.
>>
>
>Except for low power (part 15 of FCC regs in U.S.) or amateurs building
>their own equipment, you cannot legally use any home made transmitting
>equipment or amplifiers. Such equipment must be certified by the relevant
>government agency in your country. You can certainly buy a certified amp
>and use it, but you'd have a big job to get your own device certified.
>
>Check with the FCC in U.S., Industry Canada in Canada etc., for regulations.

Well, that is exactly it isn't it? I am an amateur building my own
equipment. Everything I've done so far, and that I intend to do
should be covered under section 15.23. Since it will be a home built
device, I'm not subject to certification, a declaration of conformity,
or verification. I guess that wasn't clear?


There are a very few frequencies that are totally off limits under
part 15, but not the cellular frequencies. There are some absolute
limits to power output which vary by frequency, which is what I
thought that you were basing your statement that 3 watts would be
illegal, but there are certain protections to even those limits for
home built devices. The FCC doesn't expect me to have access to the
type of equipement necessary to measure my output (whether for power,
harmonics, distortion, etc.). And, from my reading of section 15.23
and 15.5 [particularly 15.5(c)], even if I totally screw up and home
build a really noisy amp, I have not done anything unlawful.

If you think otherwise and can point me to the specific law and/or
regulation that leads you to your conclusion, I'd appreciate it. If
you know the specific absolute part 15 power limits for the 800 and
1900 cellular frequencies in watts (I have no way to determine field
strenght in microvolts/meter), I'd appreciate that, too.

If not, I'd appreciate it even more if you or anyone else can

"point me to a source for circuit/schematic information on a
cellular rf amplifier? Preferrably something in the 3 watt range and
broad enough to handle 800Mhz & 1900Mhz."