Creative i300 - TravelSound MP3 Players Manuel d'utilisateur télécharger pdf (Page 11)

ETSI

ETSI TR 102 626 V1.1.1 (2009

08)

EN 300 135 [i.3] covers FM- (or also called angle modulated) CB radio equipment having output power levels up to

4 Watts. EN 300 433 [i.4] covers AM- modulated equipment with output power up to 1 Watt and SSB- modulated

equipment with output power up to 4 Watts PEP.

The ITU Radio Regulations [i.13] definitions are 8K00F3E (FM), 8K00A3E (AM) and 3K00J3E (SSB).

Existing standards already comply with the spurious emissions and the out-of-band emissions (as defined by the

Article 1.146 of the ITU Radio Regulations [i.13] and using the limits defined in CEPT/ERC

Recommendation 74-01 [i.8].

5.3 Compatibility Issues

Compatibility tests were performed as shown in clause A.2.1.

A number of the testing team were extremely sceptical, having been involved in interference issues when CB first came

into Europe as to the possibility of using SSB modulation without interference to domestic television therefore a

rigorous test plan was agreed as shown in clause A.2.1. Testing results proved them wrong and the present TV

immunity would allow a far higher RF power than that requested without interference. The conclusions from the tests

are:

• No blocking or other kind of picture or sound degradation was visible below a CB radio interference level of

25 dBm at the TV receiver input (valid for both, SSB and AM modulation). Taking into account the minimum

isolation provided by free space propagation loss, 4 Watt AM/FM CB radiated signals as well as SSB CB

radiated signals with 12 Watt PEP appear unlikely to create visible interference to DVB-T reception.

• It was demonstrated that AM and SSB modulated interfering signals show a higher interference potential than

FM modulated interferers, however, at the RF powers requested, there was no indication of interference.

However, interference was only experienced in the presence of RF power levels far exceeding those being

considered in the present document.

• During differential mode testing, 2 UHF TV tuners broke down when applying extreme high input power to

them (estimated power load value between 35 dBm to 40 dBm at receiver antenna input connector).

Surprisingly, these two devices could be used again during the following day due to "self-healing" over one

night.

Other compatibility issues identified so far:

• The Increasingly stringent EMC requirement (within EN 60601 [i.9]) for pacemakers and other medical

implants referred to in WGRR/PT11 (98)28 annex 11 [i.10] mean that these devices are no longer likely to

receive sufficient EMF from CB radio devices to interfere in any way with their function.

• The change in use patterns from fixed (now < 5 %)to mobile (> 95 %) keep the CB equipment physically away

from domestic premises where audio breakthrough used to be an issue also as with medical implants the EMC

requirements have improved the immunity of audio equipment.

• Addition practical testing took place as defined in clause A.3.2 to encompass Domestic and Vehicle mounted

equipment for broadcast reception and a range of audio and communication devices. No interference was

recorded either to broadcast functions or audio and communication equipment.

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Creative i300 - TravelSound MP3 Players Manuel d'utilisateur Page 11