RE: Why Lower Power? (fwd)

[dan.strassberg@att.net]

For others who asked about the tradeoffs involved in 
achieving high power by use of a high-gain antenna and 
lower power Tx vs using a low-gain antenna and a higher 
power Tx.
----------------------  Forwarded Message:  ---------------------
From:    dan.strassberg@att.net
To:      "Bill O'Neill" <billo@shoreham.net>
Subject: RE: Why Lower Power?
Date:    Mon, 28 Jan 2002 17:29:32 +0000

Lower TPO and higher gain = more cost for the antenna 
and maybe a heftier tower to support it but a less 
expensive Tx and lower ongoing power bills.

I know several people who are happy to use the lower-
gain antenna and pay for the higher-power transmitter 
and the higher power bills, however. Higher gain 
antennas drop less signal into areas close to the tower 
and they are also more sharply tuned leading to really 
bizarre effects, such as a vertical pattern that depends 
on the modulation. The result can be badly distorted 
audio and picket-fencing and the like.

--
dan.strassberg@att.net
617-558-4205
eFax 707-215-6367
> Dan - Knew you'd be on this.
> Is there a benefit to having higher TPO with less gain or the other way
> around?
> 
> Bill
> 
> > -----Original Message-----
> > From: dan.strassberg@att.net [mailto:dan.strassberg@att.net]
> > Sent: Monday, January 28, 2002 12:01 PM
> > To: Bill O'Neill
> > Subject: RE: Why Lower Power?
> >
> >
> > Yes but FM powers are ERP (effective-radiated power) and
> > include the effect of antenna gain. You have to read the
> > application or the license to find the TPO (transmitter
> > power output. ERP = TPO * (transmission-line efficiency)
> > * (antenna gain). An FM with 10 kW ERP might have a TPO
> > of 3 kW, an antenna gain of 4, and a transmission-line
> > efficiency of 83%.
> >
> > --
> > dan.strassberg@att.net
> > 617-558-4205
> > eFax 707-215-6367
> >
> > > The number of bays of an FMer also has an impact, correct?
> >
> >
>