Your ERP will be around 55-60 watts given the info provided. I de-rated the dBi by 2 dB to give you dBd. I think that's correct. So your overall gain is only 1.25 dB.
Chuck WB2EDV ----- Original Message ----- From: Randy Ross To: [email protected] Sent: Thursday, October 15, 2009 9:04 PM Subject: [Repeater-Builder] Maybe a strange question... Our repeater is coordinated on a given two meter frequency. Due to terrain and other factors, we were forced to agree to some interference from a neighboring repeater, on the same frequency. The neighboring repeater is located on a peak roughly 100 miles away from us, and roughly 1800 feet higher in elevation. The repeater owner claims an ERP of 55 watts from an omni, however, I can consistently hear that repeater on my base at my QTH with an s-1 to s-3. I am transmitting 50w, 2dB loss in connectors, about 1.25 dB loss in feedline and about +6.5 dBi in antenna gain. So, I figure my ERP should be about 100 watts (+3dB = double in power, right). My antenna height is about 35 feet. So, as a newbie, I am assuming that if I can hear him at s-3, and he is transmitting 55w ERP, where my ERP is >100w, I should be able to program the radio with the proper offset and PL tone and get into the repeater. Is this a correct assumption? After all, if I can consistently hear him, the path is line of sight, right? Due to the difference in altitude, this would make sense. If all else is the same, I should be able to bring the repeater up. Or, is this repeater putting out much more than 55w ERP? Thanks!
