Re: Topband: Bi-Directional Beverage Question - DXE Polarity
1. It could be a convenient accident. 2. If on purpose, the answer is probably "Just in case this is useful". But then you would expect DXE to draw attention to it . 3. Useful that this has been "discovered" and brought to our attention. Bob VE7BS >> So other than phasing two Beverages, has anyone found a reason why >> DX >> Engineering does this? ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Bi-Directional Beverage Question - DXE Polarity
> Assuming a voltage is put on the transmission line one would have > thought the reason is not just phasing. If one studies operation of the two wire Beverage, the only effect of reversing the two wire line would be in phase of signals arriving from the feed end. That would imply that polarity of the two wire line would only matter when attempting to phase two wire beverages - e.g, parallel or staggered (echelon) configurations. 73, ... Joe, W4TV On 8/11/2011 5:46 AM, John G3PQA wrote: > From: "Mike Waters" W0BTU > Sent: Wednesday, August 10, 2011 9:57 AM > Subject: Re: Topband: Bi-Directional Beverage Question > > >> So other than phasing two Beverages, has anyone found a reason why DX >> Engineering does this? >> >> 73, Mike > > > Something I have wondered about as well. > Assuming a voltage is put on the transmission line one would have thought > the reason is not just phasing. > I have some ideas but pure speculation. > Surely someone on this group must know? > > 73, John > > ___ > UR RST IS ... ... ..9 QSB QSB - hw? BK > ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: MA160V SWR/match
On 10/08/2011 21:04, Kenneth Silverman wrote: >You could also try 10 or 12 turns of #12 or 14 gauge wire, 2" diam > across the feed point and ground. > Spread/compress the turns to get the lowest SWR/best match. > > Just to be specific: this "hairpin" match only works if the antenna > feedpoint impedance is lower than 50 ohms, The hairpin is an up-tranformer > of impedance (low to high transformation) and thus works for typical short > verticals which often have very low impedances. If it improves your match, you also gain the advantage of having the vertical grounded..thus giving you less static and noise to contend with on receive. Good luck, es vy 73 John EI7BA > If the ground system is > poor and the feedpoint happens to be above 50 ohms (indicating a lot of > ground loss), the hairpin will further increase the impedance and make the > SWR worse. > > Kenny K2KW ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
