MFJ Versa tuner II control

[KD2GOE]

Is there a simple mod or an upgraded dial that has a reduction unit in it to aid in tuning up?

 

[RatsoW8]

What model is it? I have the 948 Deluxe Versa Tuner II and I don't see any reason you would need a reduction unit.

 

[KD2GOE]

What model is it? I have the 948 Deluxe Versa Tuner II and I don't see any reason you would need a reduction unit.

it is the 949B when tuning random wire it is to sensitive..

 

[DainBramage]

it is the 949B when tuning random wire it is to sensitive..

not the tuners fault, more than likely your antenna setup is at "fault".

you are feeding the random wire against ground. ... right?

also. your long wire should be at least 1/4 wl long at the operating freq.

 

[KD2GOE]

not the tuners fault, more than likely your antenna setup is at "fault".

you are feeding the random wire against ground. ... right?

also. your long wire should be at least 1/4 wl long at the operating freq.

I have 3 50' ground wires faned out under the wire....

 

[BJ radionut]

Matt: Couple things you need to have for a random wire to work it's best IMHO.
1: It's never best idea to use a tuned length...ex: exact quarter wave length...for 75/80m a length 63 ft. or longer seemed to be a good start.
Then stay away from 1/2 wave lengths...ex: 75/80m...120-130 ft. can cause RF issues or extremely "sharp" tuning...Not that these don't work, but just my own experience OK...

2: Like Wavrider stated...You need to be feeding this against a "good" ground...
Not sure how your feeding this wire...ex: Coax running outside to your wire...etc.
If this is the case you need a ground rod at your point of connection...Ex: Center of coax to wire and shield to Ground rod. The rod is also your point of connection for your counterpoise.("radials")...for 75/80m...63-67 ft. seems to be a good length...
minimum 3... MORE is better! These do not have to be straight lines in all directions..(but it helps)...then same for 40m-20m etc...33 ft. and 16-17 ft. respectively...

Matt this is not craved in stone.... You can get by with one or none as long as your connected to the ground rod...

3: Your Tuner needs grounded as well...best that this is a second connection to a ground rod...shortest possible length...same with the radio!

4: To "pre-set" your tuner...Set your caps at mid-range (5=50%) then adjust the inductor for max receive noise...Then tweak each cap for the increase in RX signal...
This should have you close. Then TX at "low "power(10-20 watts) adjusting the caps for lowest reflected power....
Next tip: If either of the caps reaches max (say 10 on the scale) and reflected is still reducing...Quit TXing and switch the inductor switch to the next higher value...then adjust the caps again for max RX signal...
Matt, it's trail and error...sometimes the "sweet" spot on the inductor may be back a click from noise peak...
Once you find spot, write down those values and as long as nothing has changed in how the antenna is set-up, these will help speed your tune-up next time...

Here's another thing to watch: If while your adjusting you notice that when your hand touches( or removes from) the tuner the reflected changes...your not getting a"good" ground...
Hope this Helps
All the Best
Gary

 

[wavrider]

BJ covered about everything that I can think of on the long wire.

( us old farts have made most of the mistakes there is to make with different type of antennas, so we know what NOT to do).

Only thing i may be able to add is if you have a water well at your QTH, you can use this as a ground rod.

I installed my ground radials around the well casing, attached the grounds to the well casing and my 40/80 meter vertical screamed.

 

[KD2GOE]

Ok to add to this...
this is my extramarital portable setup i am testing for when i go out in to the woods it needs to fit in to a backpack. it is not being used at home

The radio and tuner are attach to a ground plate made from .25x4"x6" aluminum that is tent staked down. from that 3 50'ground wires fanned out that are tent staked down.
the radiator is broken up in to linked lengths starting from 36' and adding up to 58' & 84' then 119' depending how much i add to it..

well looks like ill have to get my counterpoise to 70'.. off to the hobby shop to fined an efficient way to rap up all the wire i am thinking of some kind of kite string winder ..

pic below is the antenna link i made