Herb, Correct me if I'm wrong but I thought I read the rules for the ARRL 160 and saw where US possessions can work US VE and DX?
73, Mark K0KX ----- Original Message ----- From: "Herbert Schoenbohm" <herbert.schoenb...@gmail.com> To: k...@optimum.net Cc: "TopBand List" <topband@contesting.com> Sent: Wednesday, November 28, 2018 1:41:08 PM Subject: Re: Topband: Polarization on 160m So is the 70-year-old Collins 74A4 with its mechanic filters and single conversion method. Many times you could just roll the IX into a deep hole with the bandpass control and the signal would pop out of nowhere. Wish I still had mine to run comparisons. I have now a modern (expensive) Flex 6600M that allows true dual diversity with 2 RX antennas with separate RX audio in each ear. I will try it out in the ARRL 160 contest although the ARRL has the VI as non-DX which is always has been a real bummer. Herb Schoneobhm, KV4FZ On Wed, Nov 28, 2018 at 1:13 PM Yuri Blanarovich <k...@optimum.net> wrote: > > Speaking of "two ears" > Going back to using two Drake R4B receivers, two antennas, one on each > ear, there would be times when "two ears" heard the signal, while > switching to each other there would be nil. I think that was some DSP > going on in the head. > BTW Drake R4B is still one of the best receivers for weak signals > reception, no crystal filters in the path to fuzzy the signals. LC in IF > chain. DSRs are now very close. > > Yuri, K3BU > > On Wed, Nov 28, 2018 at 12:04 PM, Tree wrote: > > > WIll add my two cents to this discussion. > > > > One thing I have experience with is diversity reception both on 160 > > and 80 > > meters. Often - I would be using my TX antenna in one ear and a > > beverage > > in another. On 80 meters, the TX antenna was a 4 square. On 160, > > either a > > vertical or two element phased array. > > > > I found on 80 meters - when running JAs in a contest - if I only used > > one > > antenna - I would almost always miss one letter of the JA's callsign > > and > > have to ask for a repeat... but with diversity - the signal would > > float > > around in my head and I could almost always get the whole call the > > first > > time. > > > > I can hear this effect on 160 as well as signals float around. I > > can't > > prove this is just polarization - as it could be different angles of > > signal > > arrival - but it sure re-enforces the point that having different > > kinds of > > RX antennas for different situations is never a bad thing. > > > > I have experienced some sunrise openings where a low dipole has worked > > well. There are times when my directive receive antennas seem to be > > broken > > - which is another indication of high angles. > > > > Tree N6TR > > > > On Wed, Nov 28, 2018 at 8:51 AM Yuri Blanarovich wrote: > > > >> Not knowing about "gyros", but when operating and having vertical and > >> horizontal antennas available, I remember times when QSB was > >> happening > >> on one antenna, switching to the "other" polarization antenna would > >> bring the signals up. > >> My conclusion was that at the times the signal's polarization was > >> rolling around, especially when far DX. > >> > >> Yuri, K3BU, VE3BMV, VE1BY > >> > >> > >> On Wed, Nov 28, 2018 at 09:22 AM, Robert Parkes via Topband wrote: > >> > >>> > >>> Polarization on 160m > >>> > >>> Interesting discussion and one I suspect we wish could fully > >>> comprehend ! > >>> > >>> When the wave front meets the ionosphere and the wave splits the > >>> critical frequency is different for the two waves, commonly known as > >>> foc and fxc. > >>> This difference (from memory) is half the gyrofrequency and can > >>> often > >>> be seen on Ionosonde plots with two sets of reflections. The gyro > >>> frequency depends on the strength of the magnetic field at that > >>> point > >>> of the ionosphere so can vary from 700kHz to 1.4MHz where the > >>> radiated > >>> wave interacts with the Ionosphere Layer be it, E layer or F layer. > >>> > >>> Being radio amateurs and pushing the envelope we are trying to make > >>> that illusive QSO so we need to excite a propagation path which is > >>> normally at the limit in order to chase the DX. > >>> Assuming conditions are favourable, and if the angle of arrival and > >>> critical frequency is such that it favours both wave fronts then for > >>> a > >>> single and multi-hop transmission both the O-wave and the X-wave > >>> will > >>> be propagated. > >>> > >>> The higher frequency of the two wave fronts, the X-wave may > >>> propagate > >>> which could result in a QSO whilst those around us may not have > >>> quite > >>> the same favourable conditions and only the O-wave is propagated on > >>> a > >>> differeing path while the X-Wavecould fall by the wayside and not be > >>> propagated. > >>> One result of all this variability could result in what has been > >>> called spotlight or torchlight propagation. I recall Eric K3NA > >>> giving > >>> a talk along these lines when referring to 3B7C 160m operations and > >>> how that spotlight moved across North America during the course of > >>> his > >>> opening to the US. > >>> There is a possibility that Circular Polarisation would assist > >>> with both the O and X wave modes of propagation and it could be > >>> argued > >>> that a "compromise" Inv-L antenna provides this with its Vertical > >>> and > >>> Horizontal elements making up the antenna and resulting mixed > >>> polarisation.After all a number of amateurs have had good success > >>> with > >>> an Inv-L. > >>> > >>> 73sBob ParkesG3REP(ex - S21YP, 4S7RPG, A45XF, VS5RP, P29PR) > >>> _________________ > >>> Searchable Archives: http://www.contesting.com/_topband - Topband > >>> Reflector > >>> > >> _________________ > >> Searchable Archives: http://www.contesting.com/_topband - Topband > >> Reflector > >> > > _________________ > > Searchable Archives: http://www.contesting.com/_topband - Topband > > Reflector > > > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector