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MFJ-986 tuner

 

I have a MFJ-986 tuner and would like someone with one of these? give me some "starter figures" for the tables on Page 4 of the owners manual?
Rick
 

if you look at the MFJ-989D_Manual2A manual (page 12 -13) it shows you approx. where to start
Once you have it dialed in mark the numbers down
 
Edited

The full version 2 manual does have starting values on page 12. You can find it here:
?
?
Keep in mind that your actual settings will be different depending on how long your antenna is. A short antenna (compared to the wavelength) will require more reactance and you will lose more signal in the tuner than if it is close to a 1/4 wavelength antenna. Also, as th emanual points out, there are antenna lengths that don't match well and those should be avoided.?
?
From the manual revision D:
?
To avoid problems matching or feeding any dipole antenna with high impedance open wire lines, keep
the lines around these lengths. The worst possible line lengths are shown in parenthesis:

Dipole lengths recommended (AVOID lengths in parentheses)?

160 meters; 35-60, 170-195 or 210-235 ft. (130, 260 ft)
80 meters; 34-40, 90-102 or 160-172 ft. (66, 135, 190 ft)
40 meters; 42-52, 73-83, 112-123 or 145-155 ft. (32, 64, 96, 128 ft)

Some slight trimming or adding of feedline may be necessary to accommodate the higher bands.?
?
Donald KX8K
 

Got it thanks.
Rick
WD4KQG


On Sunday, August 25, 2024 at 06:18:08 PM EDT, Frank Marks <ve1fsm@...> wrote:


if you look at the MFJ-989D_Manual2A manual (page 12 -13) it shows you approx. where to start
Once you have it dialed in mark the numbers down
 

thanks Donald
Rick
WD4KQG

On Sunday, August 25, 2024 at 08:10:05 PM EDT, Donald Hellen <donhellen@...> wrote:


[Edited Message Follows]

The full version 2 manual does have starting values on page 12. You can find it here:
?
?
Keep in mind that your actual settings will be different depending on how long your antenna is. A short antenna (compared to the wavelength) will require more reactance and you will lose more signal in the tuner than if it is close to a 1/4 wavelength antenna. Also, as th emanual points out, there are antenna lengths that don't match well and those should be avoided.?
?
From the manual revision D:
?
To avoid problems matching or feeding any dipole antenna with high impedance open wire lines, keep
the lines around these lengths. The worst possible line lengths are shown in parenthesis:

Dipole lengths recommended (AVOID lengths in parentheses)?

160 meters; 35-60, 170-195 or 210-235 ft. (130, 260 ft)
80 meters; 34-40, 90-102 or 160-172 ft. (66, 135, 190 ft)
40 meters; 42-52, 73-83, 112-123 or 145-155 ft. (32, 64, 96, 128 ft)

Some slight trimming or adding of feedline may be necessary to accommodate the higher bands.?
?
Donald KX8K

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