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KE5EHZ
01-27-2008, 01:03 AM
Hi,

I just purchased a Yaesu FT-857D along with a Little Tarheel II antenna. I dont have an automatic tuner yet, but for now I am trying to tune the antenna manually. Can somebody please explain to me how to manually tune the antenna for minimum SWR using the SWR meter on the radio. When I tried to transmit, I didnt see the meter move. It said SWR and thats it. Am I doing something wrong.

KA4DPO
01-27-2008, 01:27 AM
Hi,

I just purchased a Yaesu FT-857D along with a Little Tarheel II antenna. I dont have an automatic tuner yet, but for now I am trying to tune the antenna manually. Can somebody please explain to me how to manually tune the antenna for minimum SWR using the SWR meter on the radio. When I tried to transmit, I didnt see the meter move. It said SWR and thats it. Am I doing something wrong.


Since I'm not tooo sure how much you know please don't be offended if I Dick and Jane this a little.

Turn the RF output power on your radio down to say 20 watts. Watch the SWR indicator as you tune the antenna, it should slowly drop to a minimum. Increase transmit power and continue to tune for minimum, use CW or FM for this so that you can generate a constant carrier. Once you have reached minimum SWR turn the RF power up to maximum, the meter reading should be very low, about 1.5 to 1 or less.

John..

AL2F
01-27-2008, 01:28 AM
I use this method...tune for max signal, just by ear, you will hear the signal get stronger as you get closer and weaker as you move away. After you tune by ear, switch to pkt mode, this will put out a carrier and allow your swr meter to work properly, make sure you tune with a lower power setting 5 or 10 watts should do. Tune for no SWR meter reading, you might need to fine tune when you turn up the power.

Hope this helps good luck.

Kris-AL2F

KE5EHZ
01-27-2008, 01:40 AM
Thanks for ya'lls help. However, the display is not showing a meter for SWR. It says SWR but there is no meter like the signal meter. How do I change this??

Thanks!!

WB7DMX
01-27-2008, 02:31 AM
Thanks for ya'lls help. However, the display is not showing a meter for SWR. It says SWR but there is no meter like the signal meter. How do I change this??

Thanks!!


you don't
instead you add a external swr bridge in line with the ant.

KA4DPO
01-27-2008, 02:32 AM
Thanks for ya'lls help. However, the display is not showing a meter for SWR. It says SWR but there is no meter like the signal meter. How do I change this??

Thanks!!


Just curious, did your radio come with a manual?

WB7DMX
01-27-2008, 02:47 AM
its a vertical bar graph, if there is some standing wave it will show more bars, and if there are very many standing waves the transmitter will shut down and have no output, one bar showing is ok but it really only is a indicator of something that is not perfect match.

a bad connection will show it fluctuating up and down, it is not a true reading by any means.

W0LPQ
01-27-2008, 04:02 AM
Well ... as most of us know ... you cannot do that in any SSB mode unless you talk into the mic ... or select AM or FM and key the mic. Then the meter will show both output and VSWR.

In SSB there is NO output (or reflected) power until you talk.

K7KBN
01-27-2008, 04:59 AM
Just curious, did your radio come with a manual?

Bingo! We have a winner!

KE5EHZ
01-27-2008, 05:25 AM
Just curious, did your radio come with a manual?

Yes, it came with a manual, but it isn't very specific on certain topics. So I thought I would turn to the hams who have been doing this longer than me.

Also, there are no bars with the vertical graph. That was one thing I was questioning. I know there is suppose to be something there, but nothing shows up. If nothing else, I may just have to send it in.

WB7DMX
01-27-2008, 01:41 PM
if nothing is displayed there while transmitting and the signal is being transmitted, then the swr is fine, nothing to worry about.
you are doing this while in the am mode correct ?

K3NOQ
01-27-2008, 09:43 PM
I use the little tarheel with ic7000. Have tried it with several tuners. I would be very comfy tuning it with the manual up-down button for maximum backround noise/hiss or signal. you can watch the s-meter or listen for increase. Very easy if you can see the antenna as you tune it. If you are going down in frequency, the antenna will raise up to find resonant point. Like wise, if you go up in frequency, the antenna will shorten. Good luck with it! de K3NOQ/5 Canyon Lake Tx.

AL2F
01-27-2008, 10:45 PM
ehz -

Does your meter work in other modes Signal, Power, ALC ?

You show no SWR meter movement as you tune your screwdriver antenna up and down, using PKT, or AM mode running 10watts of power? <--you must be in a mode other than SSB!!!

I've noticed with my ft-857d that if you are running to little power you don't get a good reading on the built in swr meter....have you tried turning the power up to 20w?

What does the meter show if you have the meter set to PWR out?

Do you have another antenna to try? a dummy load?

Sooner than later you should get a seperate swr meter, a cheaper MFJ tuner would be a good investment, tuner+swr meter+power meter+dummyload.

Keep going you'll get it. Lots of times I'll overlook something simple and kick myself for it later.

GL&73

AL2F
02-01-2008, 05:28 AM
EHZ --

What did you end up with? Did you ever get the SWR meter to work? Does the new Diamond SWR meter work?

KE5EHZ
02-01-2008, 07:01 AM
EHZ --

What did you end up with? Did you ever get the SWR meter to work? Does the new Diamond SWR meter work?

Well, I just received the SWR meter yesterday, but I haven't had the time yet to work on it. With my classes, homework and studying is priority. I like to have a good amount of time to get into it and be able to troubleshoot anything that turns up. Tomorrow (Friday) is looking very hopeful. I should be able to finish grounding/bonding my truck, and get my SWR where it needs to be, and hopefully be able to make some contacts!!! As soon as I get up, I'll post it so maybe I can get a good first contact!!!

73's

KE5EHZ
02-02-2008, 02:16 AM
Ok, so even though it snowed quite a bit last night, that wasn't going to stop me from installing a good ground system on my truck. I did manage to eliminate a lot of RFI from my engine. But I still have a little more strapping to do. I hooked up the SWR meter and tuned for a min SWR and was calling out on the air; however, never received a response. So I guess I will try again tomorrow.

I do have another questions. Should there be a lot of fluctuation of SWR on any given band. For example, if I tuned for minimum SWR on the lower end of 80m, would I need to re-tune if I dialed up to the upper end of 80m. I noticed this fluctuation tonight, and wasn't sure if it was normal, or if it could possibly be indicating that I have a bad ground or something.

73's!!!

KE5EHZ
02-02-2008, 11:01 PM
*UPDATE*

So I figured out the radio, how to use everything, how to tune the tarheel, pretty much everything. I eliminated the majority of the RFI from the motor, etc, making a huge difference in receive. I can easily tune up the antenna for minimum SWR, and finally made my first contact to WA5VJY in New Mexico 960 miles away.

Thanks to everybody who replied and helped me out!!! 73's!!!