Aaronia SPECTRAN HF-2025, Руководство пользователя

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In the real world, you will find hundreds of different high-frequency radiation
sources. In the following pages, we have collected the “most popular” ones,
explaining a few peculiarities about each of them. We will be especially precise
with cell towers and cell phones, as that is the field where we receive the largest
amount of inquiries:
15.1 Portable phones (CT1+ & DECT)
Portable phones more and more replace the regular permanently installed
phone in home and office. The two most important available standards are sig-
nificantly different concerning their communications technology:
- CT1+
Transmission with this standard is analogue and not pulsed (thus not audible
even with activated demodulation) and only happens during a call . The trans-
mitting power is around 10 mW with frequencies of 885-887MHz (uplink = por-
table phone) and 930-932MHz (downlink=base station). The base station ONLY
transmits during a call.
- DECT
Radio transmission is done digitally and pulsed (at approx. 100Hz, which is
well audible with SPECTRAN with activated demodulation), even when no call
is being placed , as the base station of a DECT phone always transmits with
full power . The DECT phone, in contrast, ONLY transmits during a call and also
only when the user is actively talking. The transmitting power is approx. 250
mW at frequencies between 1.880 and 1.900MHz.
CT1+ in contrast to common misconceptions, the transmission (voice) quality is
virtually identical to that of the digital DECT standard, however, transmission is
done with very low transmitting power (approx. 10mW) and
only during a call .
Until recently, only discontinued models of CT1+ have been available anymore.
However, recently these phones reappear in shops, just because of the afore-
mentioned “optimal” radiation characteristics. Just ask your dealer. By the way,
the utilized communications standard is mentioned in the product manual and
mostly also on the phone packaging.
Please note, however, that operation
authorization for these phones expires on Dec 31 2008!
15.0 RF exposure in practice
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