as found on http://www.antennex.com/Stones/st0402/propthis.html
Richard Morrow, K5CNF, who has operated for over 40 years, tells me he remembers the Woodpecker and this is how he described it: The over the horizon radar (OTR) that many hams had to endure for years was used to track aircraft over the horizon at great ranges, often thousands of miles away. It was characterized by a pulsed type of signal that sounded like a single cylinder engine at a low idle speed. Because of this it was called the Russian Woodpecker. It was often found on the 14-MHz band and when it was there it tore up communications, jamming all of the normal ham communications beyond belief. But after a while the hams found out that if you sent a string of dits at the same repetition rate of the transmitted signal coming from the OTR for a minute or so, the operators would have to shift frequency. In this case we jammed them! No one ever got in trouble for doing this I might add. Many times this signal could be moved completely out of the ham bands by this method. The many signals that showed up to do this would render the radar useless as the weak reflected signals from the radar targets would be totally obliterated by the much more powerful ham transmissions. On occasion it would show up as low as the 40 meter band in the winter, but for the most part, the operators kept it in the higher frequency ranges above 12 MHz. The output power from this radar must have been in the megawatt range and covered anywhere from 100 kHz to half a Megahertz bandwidth at times. It was a total nuisance as it jammed any communications that were unfortunate enough to be in the signal covered by the radar. Impulse type noise limiters were not much use against it as it managed to overpower them and cause ringing in the IF strips of some rigs. It was an extremely powerful signal if the antenna was pointed in your direction. The antenna pattern was capable of being aimed in many directions, but even if the major lobe was aimed away from you, propagation would often cause the signal to show up on your doorstep via long path propagation. The receivers were not at the same location from all indications. The USA also had these radars, and they were moderately successful from all indications, but the true story on this is still classified. The Woodpecker is gone now and that is one thing not missed by most. --- "Todd, KA1KAQ" <[EMAIL PROTECTED]> wrote: > On 5/1/06, Mark Foltarz <[EMAIL PROTECTED]> wrote: > > AEA Moscow Muffler Woodpecker Blanker WB-1 > > Anyone remember one of these? > > Never knew they had a filter for it, Mark. Interesting. I do remember > hearing it march up and down the bands regularly and cursing it, > though. Wonder if anyone has an mp3 or.wav file of it? > > Good ol' Cold War ham radio nostalgia... > > de Todd/'Boomer' KA1KAQ > _______________________________________________ > Boatanchors mailing list > [EMAIL PROTECTED] > http://mailman.qth.net/mailman/listinfo/boatanchors > ** List Administrator - Duane Fischer, W8DBF/W9WZE ** > ** For Assistance: [EMAIL PROTECTED] ** > $$ For vintage radio info, see the HCI web site $$ > http://www.w9wze.org > > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com