[10m] Bob's antenna question

[Jerry]

Bob asked - 
An antenna question re ten meters
 
I currently have a G5RV, which I use with a tuner, for  80-10.     (I also 
have better ten meter antennas)
 
Question is:   the G5RV is fed with 32 ft or so of  300 ohm  twin lead, 
then goes to coax... to a tuner.
 
Loads and works poorly on ten  and thirty meters.
 
Would I be better to use all twin lead,  ( a dipole fed with twin  lead, in 
effect)  into a tuner... for all band use?  Would I  notice any real 
difference? 
 
I assume it would load better on ten , and thirty meters,,, but,,, would my 
 signal actually be any different,,, or, would it hear any better than the  
G5RV?
 
Thanks... Bob in AZBob,The inventor of the G5RV himself, had issues with the design, to the point of where it haunted him to the grave.Several attempts were made to make it resonant in places other then 20 meters.The truth be told, it is ONLY resonant on 20 meters.Using a tuner can match the mismatch, but cannot make it resonant anywhere else.AS others has said, you cannot change the length of the window line either - it is the matching network for 20 metersWhen you use a G5RV - you should not use any other type of matching network.The internal match built into most modern transceivers will match the coax to the antenna.If you read the manual for the MFJ 949 series transmatch, it says in explicit terms, do not use this matching network with a G5RV, in one direction 40 Meters, it causes arcing internally and in the other direction 10 meters, it causes heating which causes failure!Most MFJ tuners that are for sale at swap meets suffers from these issues. PERIOD!You bring the tuner home and the needles reads backwards...You call MFJ and all they will tell you is to send it to them, along with $100 and they will fix it.You think you are as smart as they are and you spend hours taking it all apart and marking where everything goes.You replace the two 1n34a diodes and you put it back together and the needles still reads backwards - 2 hours of your life wasted on someone else's mistakes.I hear the comment all the time of G5RV owners - my antenna works great on 10 meters, or my antenna works great on 40 or 75 meters.The question is - how do you know it works great, what do you have to compare it to?The lack of intelligence and the lack of Elmers today has lead us to become a group of know nothing appliance operators.Even the people who did know something, refuses to help out a new ham, or one from the CB radio era, due to the fact that they talk, but they don't want to listen.The G5RV is good for several things, if you need a piece of copper weld wire, you can rob it off the G5RV.If you need a piece of ladder line 40' long, you can rob it off the G5RV, also the insulators.The antenna design itself can be modified by making it a offcenter fed dipole by lengthening one end.Again, all it becomes is a off balance dipole..30 meters is not a division of 20 meters, hence it is not resonant on 15 / 17 / 30 / 60 meters10 meters and 40 meters are divisions of 20 meters - but the antenna was not designed to operate there, so the line impedance's when used with a piece of coax becomes almost unmanageable.Yes the tuner tricks the transceiver into thinking it is a match, and the SWR and power meter might say you are applying X amount of power and have X amount of reflection.But really all you are doing is heating up the coax and the tuner...Very little power produced is actually being radiated by the antenna.With the Johnson Matchbox - this was not so much an issue.With more modern tuners - it becomes an issue.The other problem is - what are you actually hearing?You are limited to about 60' in height and even then, the only thing you hear is the strongest signals.At the same time, all signals reduce at the square of the distance away.When you talk to someone, how many times have you heard someone conduct a net on 40 meters that says - we can't hear you, you must be on a G5RV!That sir is a insult.If you want a one antenna does all antenna, buy yourself a Barker & Williamson BWD 90 or 180 antenna.JerryWD3D