As I said earlier, I struggled with this antenna myself.
I only bought it for use on 80 meters. I also use the HyGain AV-640 which
works on 40 through 6 meters. Fabulous antenna. Worked the world with it and
it is much easier to assemble and tune. No radials required since it has 6
ft counterpoise radials 7 ft above ground.
But, that is beside the point.
These steps are the ones to follow. BUT FIRST MAKE SURE YOU HAVE SUFFICIENT
RADIALS INSTALLED. at least 10 for starters.
Also, ALSO, IF YOU CALIBRATED THE TRAPS. PUT THEM BACK TO THEIR ORIGINAL
POSITION. THESE TRAPS WERE ADJUSTED AT THE FACTORY FOR THE SPACE CADET WHO
THINKS HE CAN USE THE VERTICAL WITHOUT RADIALS AND STILL HAVE AN EFFICIENT
ANTENNA. YOU NEED TO GET TO A POINT OF REFERENCE IF YOU ARE GOING TO START
FROM SCRATCH.
1) If you have metal objects nearby the BTV, it can affect the tuning. (
Tower, another antenna, etc.) Keep the BTV at least 30 ft from other metal
structures and antennas.
2) Use a short ( 5 ft or less ) coax from the MFG to the antenna during
adjustments. This eliminates the potential of coax length affecting the
tuning.
3) Do not install the 17 meter trap right now, install it AFTER all other
bands have been adjusted.
4) Start from the bottom up. Tune 10 meters frst. Then 15, then 20. The 10 m
trap and tubing below it affect the next bands . Likewise, the 15 m trap and
tubing below it affect the next bands
5) Do these steps for each band.
6) Go back and check with the MFJ all bands starting at 10 meters , then 15,
then 20 etc.
It is unlikely that one of the traps is bad. It is just a coil and
capacitor. The capacitor is the metal can around the coil .
Each coil inside the cans adds inductive loading for the next band and all
inductances add up to make the antenna short on 40 meters.
You might make a chart of SWR vs. Frequency while you are tuning it and keep
it with the manual for future reference. ANd also, maybe email it to us for
examination. It will tell a lot.
ALso, your MFJ will tell the reactance ( X ) capacitance ( C ) and
inductance ( L ) at low SWR which is useful info.
Dan Schaaf
K3ZXL
"In the Beginning there was Spark Gap"
www.k3zxl.com
----- Original Message -----
From: "Michael Baker" <k7dd@cox.net>
To: "'Tower and HF antenna construction topics.'" <towertalk@contesting.com>
Sent: Wednesday, January 20, 2010 11:14 PM
Subject: Re: [TowerTalk] Hustler 5BTV Problem
> Hello Kelley and the group,
>
> Having owned one of these in all of their variant and currently
> owning a well used and rebuilt 7BTV (6BTV with 17 meter add on kit) I have
> a
> few suggestions.
> Make up a length of coax that is ELECTRICLLY a half wave at 3.55 Mhz
> and use it as your feedline. Preferably something larger in size like RG8
> or
> RG213, 9913, etc. You can use your MFJ to cut it to length.
> This gives you half wave multiples for each band except 15 meters.
> IF the feedline is not underground except for the small length near
> the antenna then you will need to make up some solenoid chokes to keep the
> RF off the line. 8 to 10 turns around a large soda bottle works ok and is
> cheep for testing, wrap with duct tape to hold it on. I did this for 6
> years
> in the sun and it worked fine. The first one should be near the feed point
> and another just outside the ends of the radials IF they are above ground.
> If not, just at the feed point is good.
> This will take the feedline out of the equation and give you a
> reasonably accurate measurement of the antenna at the end of the coax.
> I tend to agree with the fellow that suggested that the 20 meter
> trap might be a problem. IF your measurements (physical) between the end
> of
> the tubing and the end of the trap cover are all following the same ratios
> for each trap (in spec) and adjusting the trap outer metal housing doesn't
> bring the adjustments in line then the 20 meter trap may be either
> installed
> upside down (switched end for end, but unlikely as it would look weird and
> be pretty obvious) or there is poor to open contact between the outer
> metal
> shell of the trap and the lower tube (corrosion, coatings, etc). The trap
> may have been incorrectly assembled at the factory and is not a 20 meter
> trap but had been marked as one. (Rare, bit no one is perfect.)
> The full length of the antenna (not including the top loading coil
> for 75/80 meters) is the length for 40 meters so the 20M trap issue must
> be
> fixed first.
> I am assuming you do have the 6 metal spikes/top hat in place
> because you said it was a 5BTV.
> Leave the 75/80Meter coil and whip OFF the antenna while doing these
> tests as it only makes the antenna top heavy while raising and lowering it
> for adjustments and when you get everything working up to 40 meters, then
> you can install the top coil and tune it for its band. It will have almost
> no effect on the 40 meter tuning. Perhaps a bit of a shift down in F for
> 40
> which you can adjust for in the end.
> Too bad you are so far away as I would be glad to give you a hand
> with it but the drive from Phoenix might be a bit prohibitive. ;>)
> Keep us/me posted with your results.
> Push comes to shove, you might have to ship the trap back to Hustler
> and have them evaluate or replace it.
> IF you happen to have a buddy in town who has a spare 20Meter trap
> you could borrow, you could just swap it out and see if it tunes up then.
> Good luck.
> When they are working, the work quite well.
> 200+ countries worked the first year I had it installed here at this
> QTH, 40M in the mornings, 20M daylight hrs, CW ONLY, 135W Output from an
> old
> C-Line and I worked swing shift M/F. so, the DO work.
> Let me know if I can be of any further help.
>
>
> Michael Baker K7DD
> k7dd@cox.net
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Kelley
> Sent: Wednesday, January 20, 2010 6:55 PM
> To: Tower and HF antenna construction topics.
> Subject: Re: [TowerTalk] Hustler 5BTV Problem
>
> I can certainly add 10 feet to the coax, but, as I should have mentioned
> up front, the SWR measurements were taken using an MFJ analyzer
> connected to the antenna with about 6 feet of coax.
>
> Kelley - W0RK
>
> On 1/20/2010 7:07 PM, Mike Murphy wrote:
>> Just a guess, but your 60 feet of coax is suspect here. Try adding 5 or
> 10 feet of coax and I bet your problems go away.
>>
>> Good Luck!
>>
>> __________________________
>>
>>
>> Michael Murphy - KD8OK
>>
>>
>> kd8ok@yahoo.com
>> __________________________
>>
>>
>>
>>
>> ________________________________
>> From: Kelley<kshaddrick@jetup.net>
>> To: towertalk@contesting.com
>> Sent: Wed, January 20, 2010 6:47:32 PM
>> Subject: [TowerTalk] Hustler 5BTV Problem
>>
>> I've been working with a 5BTV antenna for about two weeks now. I've got
>> good SWR readings on 10m, 15m and 80m. Higher but usable readings on
>> 20m. However, I can't get anything under 2.0:1 on 40m. The antenna is
>> ground mounted with 20 25' radials. It's fed with about 60' of coax.
>>
>> I've tried the normal tuning as well as adjusting the traps. Nothing
>> seems to bring the SWR on 40m down to something usable.
>>
>> Anyone have any ideas I can try?
>>
>> Kelley - W0RK
>> _______________________________________________
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