Because you do not know when a call, when you are making a call you extend that; now between an antenna that is extended and an antenna that is in its compact position there is a difference of gain. So, that let us just say is 4 dB is a difference in gain between what you would if you had a telescopic antenna.
क्योंकि आपको पता नहीं है कि आप कब कॉल कर रहे हैं, तो आप इसे बढ़ा सकते हैं; अब एक बढ़ाया गऐ ऐन्टेना और एक कॉम्पैक्ट स्थिति वाला ऐन्टेना में 4 dB जितना गेन का अंतर है।