 |
| http://media.adn.com/smedia/2014/05/14/19/42/1qEGYg.AuSt.7.jpeg |
I
was fortunate to get a tour of the site about 10 years ago as my friend
Steve W4YHD was the Chief Engineer, quite impressive! I have some
photos (35mm film, not digital) which I need to scan. The HAARP
transmitters were true AM transmitters as they were used to heat the
ionosphere and generate e.l.f. waves by modulating the carrier with low
frequency audio tones, very inefficient (but all elf transmission
schemes suffer from lack of efficiency),many megawatts of HF energy
used to excite milliwatts (or perhaps microwatts?) of elf radiation from
the ionosphere.
I recall that they had a Radar on site and were supposed to shut down
in case an aircraft flew through the beam. They also had an ICOM R72
receiver so they could listen before transmitting so as not to cause QRM
! The whole lashup was powered by a series of 5 generators driven by
diesel locomotive engines. The transmitter was actually a bunch of
final amplifiers, solid state driver and a 3cx5000 PA tube, housed in
trailers below the antenna array, each trailer housed a number of
3cx5000 PA's - the PA's were fed by an HP synthesizer (don't recall the
model #, might be in one of my photos) and fed with equal lengths of
coax so all PA's would be in phase. There was a method to shift the
phase across the array so as to change the shape and direction of the
beam. The antennas were bow-tie dipoles broadband from 3-10MHz. The
whole thing was controlled by Sun Sparc workstations from a master
control room. Just for fun I tuned up one of the transmitters on 7.290
MHz AM to see if I could strap Ashtabula Bill W8VYZ, of course it was
daytime and I don't think anybody was affected!
Was hoping to make a return trip to see the fully built out site but its looking very questionable at the moment.
73 Warren K2ORS"
1 comment:
I too find it sad that the pseudo-science "social networks" have probably condemned this project to the scrap heap because of all the rubbish that had been said about it (headaches, weather etc..) Shame there was no high-level explanation of the real purpose, or how little effect it actually has. We live in a world now dominated by Twits that tweet.
G6AIG Hugh.
Post a Comment