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View Full Version : best way to tune sticks for gain help



1iwilly
04-19-2012, 08:37 AM
hello to all new to the board
i'm looking for the best way to tune 2 straight sticks 3/4' stick in stick at 80' spacing. runiing as a bounce back set up when i say tune i mean for forward gain they are already tune for lowest SWR/reflect i have a ic engineering digi-field strength meter a stock cobra radio bone stock for testing i made a dummy plug with 30 feet of speaker wire to pin 1=shield and pin 3 and a push button at the other end to key and un key the radio from where i'm standing what is the recomended feet to be in front of vehicle i hear 10,20,0,50, and the list goes on this is only for 2 stick no other antennas will be added just to drop the hammer on the locals with !/2 their power thanks

noisemaker
04-19-2012, 12:23 PM
Set em just as if you were setting coils. Set the hot, move it to rear- and then set the hot. You can probably tweak the back door once you have em in the ball park. once you get there, the try tweaking the front some more if needed. Check your field strength each time you think you have it and write it down!!!

DONT tune while skip is rolling! It will give you inaccurate readings because the d layer is hot. Set em at night or on a rea

1iwilly
04-19-2012, 05:09 PM
Set em just as if you were setting coils. Set the hot, move it to rear- and then set the hot. You can probably tweak the back door once you have em in the ball park. once you get there, the try tweaking the front some more if needed. Check your field strength each time you think you have it and write it down!!!

DONT tune while skip is rolling! It will give you inaccurate readings because the d layer is hot. Set em at night or on a rea
yes that is how there were tune but i'm having and issue where i have 2 diff setting that give me the same exact readings as far as swr,r,x rite now the rear is 9' taller than the front now if i lower the rear
3' so i'm only 6 'taller than the front one i have the same swr,r,x even reflect is the same
i know the 80'spacing and tube diameter plays a role now here is the trickie part at 6' taller if i try to go lower to get more gain i see none on the meter now when i go up a 1/2 at time i see the gain going up
and i end up back at 9' taller than front i try to lower/raise the front but gain nothing i hear people talking about tuning for gain but i can't seem to see unless i'm already seen all the gain i'm going to get

High Voltage Mobile NJ
04-19-2012, 05:22 PM
the easiest way to tune is to tune the first antenna . get that around a 1.1 or a 1.2 you dont have to get it flat. leave the antenna on . then get ya other antenna and go about 3 inches higher than the first one . bump it down going to some base stations that you can trust and tell them to listen how loud u are and what is ya signal in S Units . try raising the back door up 3 inches more then about 2 inches more at a time. if ya station is more than 50 miles away the antenna 6 to 12 inches of height more on the back door will give ya more gain in groundwave and skip conditions, local you want your back door to be just a couple of inches higher than your front hott antenna.dont worry so much about gain coming out looking at a field strength meter , that is just a reference somewhat . try that and then keep us posted . we will get ya talking strong breaka breaka . :slow:

1iwilly
04-19-2012, 07:16 PM
the easiest way to tune is to tune the first antenna . get that around a 1.1 or a 1.2 you dont have to get it flat. leave the antenna on . then get ya other antenna and go about 3 inches higher than the first one . bump it down going to some base stations that you can trust and tell them to listen how loud u are and what is ya signal in S Units . try raising the back door up 3 inches more then about 2 inches more at a time. if ya station is more than 50 miles away the antenna 6 to 12 inches of height more on the back door will give ya more gain in groundwave and skip conditions, local you want your back door to be just a couple of inches higher than your front hott antenna.dont worry so much about gain coming out looking at a field strength meter , that is just a reference somewhat . try that and then keep us posted . we will get ya talking strong breaka breaka . :slow:

well my reflector when in the hot is tune 1.1 r=48 x=4 total length is 102 using the mfj 259b so you are saying leave it there then make the back one 3' taller and tune until lowest is reach is that the way you want me to tune it.??

noisemaker
04-19-2012, 07:25 PM
How long is your coax and what type of coax is it?

JesseJamesDallas
04-19-2012, 07:41 PM
You need to tune so X=0...

You say your back antenna is 9" taller than the front, and if you lower it 3" none of your readings on the MFJ changes, can't be right...Something should be changing if you lower the back antenna by 3"...Most likely "R" will change slightly which is the ohm reading if I remember correctly, and "X" should change...

You probably don't have X=4 on all 40 channels. Find out which channel has the highest X=? and then see what channel X changes at...Then lower or raise the back antenna and see which way you need to go to get all channels to X=0...Once X=0, then you may need to tweak the front antenna to get R and SWR back where you want them...

SWR "may-not" necessarily be 1.0 -1.1 on the MFJ to get X=0 and R around 50ohm.

coolbreeze
04-19-2012, 07:52 PM
shakes head.

1iwilly
04-19-2012, 08:15 PM
How long is your coax and what type of coax is it?

12ft of belden 9913f spacing 80'

1iwilly
04-19-2012, 08:17 PM
shakes head.
mind your p and q breeze working on something here. hehehehe damn u r everywhere

doughboy
04-19-2012, 09:09 PM
i tuned mine the way noisemaker mentioned and they are real tight turn my truck around guys drop 5 or 6 s units
also like JJD said area of most forward gain or x=0 may not be the best swr reading you may read 1.1 1.2 at your highest forward gain so unless you're competing probably best to find a compromise somewhere in the middle

coolbreeze
04-19-2012, 10:19 PM
willy, you cant accept the fact that you had it right the first time can ya LOL.
you better stop using that mfj and use a bird meter.

max gain will be r=50 and x=4 to 6

JesseJamesDallas
04-19-2012, 10:24 PM
willy, you cant accept the fact that you had it right the first time can ya LOL.
you better stop using that mfj and use a bird meter.

max gain will be r=50 and x=4 to 6
Why do you say X=4 or 6? I have always herd you need to have x at 0...and not be so concerned with SWR @ 1.1 with R= 46 to 52........

High Voltage Mobile NJ
04-19-2012, 10:40 PM
because you tune for maximun gain for a keydown , not for lowest reflect

1iwilly
04-20-2012, 06:27 AM
willy, you cant accept the fact that you had it right the first time can ya LOL.
you better stop using that mfj and use a bird meter.

max gain will be r=50 and x=4 to 6

breeze is not so much about that. it is about proving a point to the ducks here in BPT CT that i can beat them with half the power they use 16 pills 2 alts 4-8volt batt 2 antennas while i'm my 2x8 no alt only a 6 and not just any 6 volts + 12 for volting but i'm making up the rest on the antennas i have already beat them but i'm looking for that final beat down they forget to increase a 1/2 s unit u have to double your power well isn't that going from an 8 pill to 16 does so i'll let the sticks do the rest. some of you guys might of heard them out there big bully number 9 aka hanging judge and dr reverend macnasty. thanks for the replies and advice

coolbreeze
04-20-2012, 08:13 PM
Jesse, r=50 and x=4 is still a 1.0 swr. typically 1% reflect is where I find max gain and thats at a 1.15 swr.
If you had r=50 ( ohms ) x would have to be 5-7

if you had a r=48-52 and x=0 you would have a 1.0 swr on the mfj

1iwilly
04-21-2012, 05:59 AM
well little more testing today by the way this is the meter that i use i just got laid off until sept so plenty of time in my hands that is after the honey do list of course
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