no ground wire hooked to mast-mast in the ground.
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maco 5/8 to maco .64
- Thread starter 1342
- Start date
insulator.update i took the extra small radiator out of the antenna and managed to get the regular antenna to stretch out to the same 22-10 inches results are 27.555-1.3,27.385-1.3,dip in the middle but still not broadbanded still working on it!PS-w5lz thanks for all your help,i hope i am not being a pain in the but i bet you have answered many of my questions a 100*before.
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1342,
i think you need to start keeping a chart of your SWR curves, and also the least amount of reflected power as you make your adjustments.
like, pick a length for the radiator, starting with the shortest length you think should work well.
then move the wire all the way to one side of the tuning ring.
test the SWR at the top, middle and bottom of the freq range you are tuning for, at the same time make a note of the percentage of reflected power you are getting.
draw the SWR curve on a piece of paper.
now move the wire about an inch on the tuning ring.
make another chart.
keep going all the way around the tuning ring at this length, charting all the way around.
now increase the length by 3", or 6" or whatever you think is best, move the wire to the same starting point on the tuning ring you used before and do another set of charts all the way around the ring, noting the reflected power along the way.
if you keep doing this until you get past the max length that you think should work well, you will have a nice piece of data to ponder over without having to go outside.
after looking at the charts over and over for a while, you will get a picture in your head of where that magic spot is that is a combination of bandwidth, low SWR and small percentage of reflected power.
yes, this seems extremely tedious, but in my experience, trial and error can leave you sleepless at night trying to remember whether or not you tried everything.
oh, and you are removing that ladder when you go inside to do your SWR readings right?! LOL J/K!
good luck with it, im anxious to see what you find out as i plan on buying one of these antennas sometime this year.
LC
i think you need to start keeping a chart of your SWR curves, and also the least amount of reflected power as you make your adjustments.
like, pick a length for the radiator, starting with the shortest length you think should work well.
then move the wire all the way to one side of the tuning ring.
test the SWR at the top, middle and bottom of the freq range you are tuning for, at the same time make a note of the percentage of reflected power you are getting.
draw the SWR curve on a piece of paper.
now move the wire about an inch on the tuning ring.
make another chart.
keep going all the way around the tuning ring at this length, charting all the way around.
now increase the length by 3", or 6" or whatever you think is best, move the wire to the same starting point on the tuning ring you used before and do another set of charts all the way around the ring, noting the reflected power along the way.
if you keep doing this until you get past the max length that you think should work well, you will have a nice piece of data to ponder over without having to go outside.
after looking at the charts over and over for a while, you will get a picture in your head of where that magic spot is that is a combination of bandwidth, low SWR and small percentage of reflected power.
yes, this seems extremely tedious, but in my experience, trial and error can leave you sleepless at night trying to remember whether or not you tried everything.
oh, and you are removing that ladder when you go inside to do your SWR readings right?! LOL J/K!
good luck with it, im anxious to see what you find out as i plan on buying one of these antennas sometime this year.
LC
loose cannon i am getting closer and got more pics.so far i have a length of either 21-1/2 inch radiator or 21-9 1/2 inches entire length with the dip at 32 and 1.15 and 38 at 1.2 and 55 at 1.3 maco states to measure the full length from top to bottom.the loop gap is still at 3 inches maco calls for 1 inch.groundplanes are 3 inches maco calls for 1/2 inch from bracket.changes so far are as follows, drilled rivets out of pl-259 and replaced with nuts and bolts,changed crappy wire to 12 gauge double insulated copper(should help when it rains)also increased the length of this tap wire by one inch just in case i have to make a bigger loop,better connector for the tap and a gromet over the pl-259 connector(no more rain there haha).
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nice changes.
do you have a station a few miles away to tell if you are making a positive or negative difference in signal radiation?
LC
do you have a station a few miles away to tell if you are making a positive or negative difference in signal radiation?
LC
i just did a couple of radio checks at 10 miles 8 foot of the groun and the 1 guy i usually talk to said i was 30s units and the other 10,i usually hit the first guy at 30 when my antenna base is at 40 feet so i am going to mount it and try again.i think the other guy i also usually hit at 10 but thats at 40 feet.gonna have to try it out its been down all week.
ok a confirmation from a guy in canada i talk to regularly that i hit at 3s units said i was 3.5 almost touching the 4 so 1/2 to almost 1 s unit increase with 21 feet 9 1/2 inches so far my receive is better gain about the same 1/2 to 1s unit my match after getting it back up went to 1.1 to my surprise across the intended band and further.i increased the loop gap to 4-5 inches and adjusted the tap point again.not done yet but had to give it a try before the next session!
cool!
im going to do the same sort of experiments when i get my maco, but that wont be for a while.
if you have a field strength meter handy, you can watch the real world signal increases and decreases your changes are making.
i cant wait to put up a real antenna again!
i have an inverted V up on the roof, but it leaves a lot to be desired. LOL
have fun!
LC
im going to do the same sort of experiments when i get my maco, but that wont be for a while.
if you have a field strength meter handy, you can watch the real world signal increases and decreases your changes are making.
i cant wait to put up a real antenna again!
i have an inverted V up on the roof, but it leaves a lot to be desired. LOL
have fun!
LC
cool beans i had this first one up after the imax snapped i think it worked better than the antron that was on the top of that same mast and the second one is up there now 33 foot loop in a different spot but once i get the maco finished i will use the mast as a hanger to my other roof with another hanger to hang this loop vertical.
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ok well i dont know about antenna theory however this midland is now 23 feet with out the matching coil and total antenna 23 1/2 feet i mounted 2 whips at the bottom and trimmed them down to 4 feet 2 inches each.my match is shocking workable 26-29 mhz and flat accross almost 2 bands.i used this last night with a trc-209 walkie talkie mounted about 7-8 feet with 3 watts out.2 stations one 10s units and the other 8-9 from about 10 miles.i will be mounting this about 25-30 feet tonight for additional testing and then pulling the maco back down.
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on the ground those whips worked perfectly but when i got the antenna in the air the match went south! i ended up taking the whips back off and isolating the mast from the antenna bracket.the weird thing is i have a peice of fence post mounted to the back of my garage and i just drop the mast into it with a hose clamp to position it and that section of fence post with the mast was acting like a matching network.to match the antenna to the new .64 length all i had to do was drop the mast into the fence post and adjust for my dip!wow any comments would be appreciated!
B
BOOTY MONSTER
Guest
its not a maco but my homebrew uses the same basic tuning method . i initally had the vertical 23 feet long but now its at 22 1/2 feet . i used pretty large tubing for my verticle , 1 3/8 , 1 1/4 , 1 1/8 and 1 inch at the top with a 1 inch wide by 1/8 inch thick aluminium strip for the tuning ring .
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