I don't claim to know much about AM stations, but FM stations are rated for some amount of equivalent power. When you hear "500kW" or something it's always much lower power with a higher antenna with more bays. -- Martin K Richard Prosser wrote: > Alan, > I never got up the mast, the one time I was offered a trip up I chickened > out & have regretted it ever since. > We knew one of the riggers and he was not very complementary regarding the > state of the structure - & this was in the late 1960's. The mast is, of > course, still standing but has probably been replaced part by part several > times since then. > > IIRC one of the hazards at the top (apart from the obvious) was that the > field strength was about 1kV/m so you were advised to keep below the top > rail as otherwise you would add to the effective mast height (700ft?). > > Although the transmitter was rated at 500kW, I was told it wasn't run at > this level, 100kW ? being nearer the mark. Trying to extend the output tube > life. Big water cooled buggers. > > 2ZB & another station I can't remember (a part time station) ran on a > slightly smaller mast nearby and the Radio NZ SW transmitter was also on > site. Right next to the golf club where Michael Campbell learnt his trade. > > RP > > > On 22/11/2007, Alan B. Pearce wrote: >>> If it's the place I'm thinking of (Titahi Bay) I used to live there. >> Yes, that's right. My grandparents lived at Plimmerton. >> >>> In dry conditions you could go up to the farmland under the mast, >>> pull an arc off a fence line & listen to the radio! >> I went for a visit to the transmitter as part of the course I did during >> my >> apprenticeship. The stories that got told of various things that happened. >> >> The taller of the two masts had both 2YA (570kHz IIRC) and 2YC (620kHz?) >> fed >> to it through a combining & tuning network, with the mast length being >> tuned >> between the two. There had been a lightening strike a couple of months >> before our visit, and the station techs had stories about molten copper >> pouring out of the combining network running around the floor. I hate to >> think what the 500kW transmitter (2YC was only 60kW or 100kW IIRC) thought >> of this sudden lack of load. Anyway apparently the techs lashed up a >> direct >> connection to get 2YA back on the air as quick as possible. >> >> Another trick was to climb the mast. There was a platform that you stood >> on >> and then jumped across to a similar platform on the base of the mast so >> you >> were not attempting to ground the transmission power through your body ... >> The mast cross section was large enough that you climbed inside the >> lattice >> structure, so were not subject to the voltage fields. It would take around >> half an hour (if you were good and fit) to climb to the top. Apparently >> someone who had done this had peed out through the lattice, and the >> resulting liquid stream followed the a curve that represented the field >> intensity around the mast. >> >> -- >> http://www.piclist.com PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist >> -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist