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Need help getting on the air

Jun 4th 2012, 02:05

KF7SXD

Joined: Dec 13th 2011, 23:51
Total Topics: 0
Total Posts: 0
Please forgive my ignorance; I'm still very new to this field and trying to learn as I go. I have newly risen to the ranks of General, and still haven't actually enjoyed a QSO.
I have built three different DIY antennas, with mixed results. In each case (to varying degrees) I can receive but cannot transmit far enough to get a response. My guess is that the problem involves my feed line.

Radios are a Kenwood TS-430s and a Yaesu FT-817ND. They are connected to a tuner through a T connection, with only one radio in use at a time. I've tried an MFJ 934 tuner and an LDG Z-100Plus. I am unable to get a match with either tuner. I attributed this to my inexperience with the MFJ-934, and so got the autotuner. The Z-100Plus is also unable to get a match. I'm running RG-8 coax through a pvc pipe to get it through my wall and outside. I also use this pipe to run a 10ga copper wire to ground. All gear is connected to the ground lug on the tuner and then out through the wall to a 10' ground rod.
The first antenna was a skyloop mounted along the eaves of the house and then up hill behind the house to a pair of 10' PVC pipes, resulting in a square approximately 50' on a side. The second antenna was based on a random wire described here in the longwire topic in the forum (84 feet of landscape cable with one connector snipped at 25 feet). When this antenna was hung in an L up to the corner of the house and then out to one of the uprights for the skyloop and then draped on the ground. It worked best of any I've tried in this configuration for receiving, but when I hung it up along the fascia board on the eaves, it no longer works at all.
The third antenna I've tried is a single wire random, 41 feet. This one receives well but again, no joy in the transmitting department (as in I try to check in to a net and no one in the region around me replies or appears to notice that I am transmitting.
I would feel better about experimentation if I knew that I had a setup that actually works first. Right now I am so frustrated by failure that I am ready to give up. In this case, giving up means buying a commercial antenna and better coax feed cable.

What I really need, short of a solution, is some new suggestions of things to try. I've run out of ideas to keep troubleshooting. I have used separate antennas (I have a Miracle Ducker for the FT-817) to transmit and I coud hear on the Kenwood. Otherwise I would be thinking that my radios were simply unable to transmit.

The other request I have is an idea of how well a multiband vertical antenna would work for me, and whether that would be worthwhile. I've been looking at the Hy-Gain AV-18VS and about 100 feet of LMR400 UltraFlex coax to feed it.

Please help. I'll do my best to answer questions.
Jun 4th 2012, 04:45

KM3F

Joined: Mar 6th 2008, 13:50
Total Topics: 0
Total Posts: 0
First if I read correctly you have two radios TEEd togather.
That is a no-no. You are driving power into the other radio not in use and may damage it plus the output match may be very poor.
This causes the radio to turn power back to protect it'self.
Set up for only one radio connected to the tuner.
I don't know what antennas you have but need one that the tuner can load into and get the SWR down to at least 2 to 1 or it will cause the radio to reduce power as well and you cannot be heard very far.
Have some means to see the SWR as you tune the tuner in CW mode at low power, then switch to SSB, turn the power back up to make your call.
BTW do not do this on or near a frequency in use or you cause QRM to others.
Best to tune into a dummy load then transfer to the antenna and touch up the tuner in a short amount to time..
Good luck.
Jun 4th 2012, 05:55

KF7SXD

Joined: Dec 13th 2011, 23:51
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Total Posts: 0
Thanks for the reply. Wow, I just hope now that I haven't fried my radios.
Jun 4th 2012, 18:58

KF7SXD

Joined: Dec 13th 2011, 23:51
Total Topics: 0
Total Posts: 0
I separated the radios, connecting only the TS-430s to my random wire antenna, and used the FT-817ND with the whip antenna. I was able to briefly transmit from one and hear on the other in both directions. I'm hoping this confirms that they can both still transmit.

Is there a safe way to connect two radios to the same antenna, such as a switch? The FT-817 is primarily for portable use, but it is easy to connect to the computer for use with HRD, whereas I don't have a way to connect a control cable to the TS-430s. Not a requirement, but would be nice to have the capability to use both at home.
Jun 4th 2012, 19:07

K0BG

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Using an antenna switch is the best way, however, the switch in use must have good isolation, or you still run the risk of zapping something in the front end circuitry. The isolation is generally given in dB, and anything greater than -60 dB should be fine.
Jun 4th 2012, 21:48

W0BTU

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Quote by KF7SXD
... I was able to briefly transmit from one and hear on the other in both directions. I'm hoping this confirms that they can both still transmit.

I hope so, too. :-)

What you really need to do is measure the power output. It's possible that you're hearing the driver stage and you've fried a component in the output stage in one or both rigs. If the rig puts out full power into a low SWR, then you most likely got lucky.

If you don't have a wattmeter, the rig might have one built in (my transceiver's S-meter can function as a power output indicator). Otherwise, just get on the air with it and hope for the best.

73, Mike
www.w0btu.com
Jun 5th 2012, 04:14

KF7SXD

Joined: Dec 13th 2011, 23:51
Total Topics: 0
Total Posts: 0
I went back to the manual and got the directions to switch to power meter mode on the display. The FT-817 shows P0, so it appears to be fried. The Kenwood, on the other hand, worked for a couple minutes after turning it on and then reverted to no power on output. It worked just long enough to get a good match from the autotuner before dying again.

The good news is that the tuner was able to give me a 1.2:1 match on the TS-430s, so I can tell the random wire works. The bad news is that I have two radios that can't transmit and now I get to talk to Yaesu about repairs.

Thank you all for the help.
Jun 5th 2012, 18:12

WA0CBW

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Mike,

Don't give up yet. If you are in the sideband mode there won't be any power out until you talk into the microphone. Try putting the rig into the CW mode and using the transmit button or a code key to put the radio into transmit. Hopefully there will be some power out. Also only key the transmitter for short periods until you figure out what is going on.

Good Luck

Bill
Jun 5th 2012, 19:35

W0BTU

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
I agree, talk into the microphone in the SSB mode (or put it in CW or RTTY mode like Bill said) and see if you get a power output reading then.

And don't assume that a low SWR means the antenna is working. I noticed you're using an end-fed wire, but the the only ground you're using with it is a 10' ground rod. That's not a very good RF ground. Check out http://www.w0btu.com/Optimum_number_of_ground_radials_vs_radial_length.html

Based on my experience with my average soil, if I had a choice between radials or ground rods, I would use only radials. They work THAT good.

A ground rod is mainly for lightning protection. But we still need to properly bond all the grounds together to accomplish that.

An end-fed and a ground rod was my first attempt at an antenna over 35 years ago, too; but there are much better antennas. I suggest building a simple center-fed dipole. They don't require radials and they put out a great signal! All you need is a single mast, tree, tower, etc. as a center support.

73, Mike
www.w0btu.com
Jun 7th 2012, 18:19

W0BTU

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
How it is going, Mike? One thing I should have thought of before: it is more likely that your receiver sections would have failed first, before the PA or T/R switching circuits. If you can hear signals on those radios, that's a good sign.

Don't be afraid to ask for more help! That's what these forums are for. :-)

73, Mike
www.w0btu.com
Jun 7th 2012, 18:42

WB8ZTP

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
KF7SXD wrote >>> The other request I have is an idea of how well a multiband vertical antenna would work for me, and whether that would be worthwhile. I've been looking at the Hy-Gain AV-18VS and about 100 feet of LMR400 UltraFlex coax to feed it.

Todd,
I’m using a ground mounted Cushcraft R8 vertical and have been VERY HAPPY with its performance. In just over 2 years I’ve worked every state and 26 countries with just a limited operating schedule. I’m still in the work force to pay for my Ham Radio habit! I bought it from Universal Radio in Reynoldsburg, OH. It doesn’t need any radials which is a nice feature. I have it mounted ~ 7 feet off the ground on a stick of 1 1/4” rigid conduit. I guyed it with some parachute cords due to the many reviews on eHam.net suggesting the guys. In fact I decided to post a review today on eHam.net since I’ve been so happy with it. It won’t show up until it’s reviewed by the editors though.

I started the Longwire Antenna topic on the ARRL Forums and have been happy with all the responses. I just posted my experience with my first try with a Longwire / Random wire antenna. It worked great, check the latest post out. I also got a lot of email suggestions from folks instead of them posting on the ARRL Forums. I have my email address listed on the QRZ.com site. A lot of folks use it to look other Hams up. You might want to update you QRZ listing when you have a chance. Look me up and send me an email if you wish on any other questions, tuners, radios, dipole antennas… always glad to help!

73, Mark
WB8ZTP
Jul 8th 2012, 23:14

KF7SXD

Joined: Dec 13th 2011, 23:51
Total Topics: 0
Total Posts: 0
I'm still using the end-fed wire, but I have added some radials to see if that would improve things. I added a quarter wave wire for 80m, 40m, and 20m so far. Right away I saw a difference in reception. I'm still undecided about whether I will continue to use this wire antenna or upgrade to something better. I'm leaning toward a vertical that I can maybe hide between the trees at the top of our property.
I have a question about creating an RF ground. I was reading an article that tells me it would be good to run a long counterpoise wire (such as around the entire house) and the author said to "tie it at the feed point" but I'm really not sure where exactly that is. Do I connect the counterpoise wire at the tuner ground lug where the AC ground is connected? Or is it out where the surge ground wire connects to the ground rod?
I sincerely appreciate the help, folks. I'm learning a lot, but I'm lacking in some basic fundamentals I think. Thanks also for being patient. :)
Jul 10th 2012, 17:18

WA0CBW

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
For a vertical antenna the RF ground would consist of a series of wires laid out radially from the base of the antenna. A good start would be four 1/4 wavelength radials for each band. Don't worry if you can't make them a full 1/4 wavelength for each band. I have used my trap vertical for many years without radials and it works OK.

It is recommended that the RF ground also be tied to the electrical ground. Simply extend one of the radials and connect it to your electrical ground or the point where you have connected your single point ground. (A counterpoise ground running around your house might be useful if you are using an end fed attic antenna or any antenna that requires a ground.)

Have you tried a dipole antenna? These are the easiest antennas to build and work very good. If you feed it with ladder line or open wire feedlines and use a balanced tuner it can be an all band antenna. If you have problems getting the balanced feedline into the shack check out the ARRL Antenna Handbook on using two pieces of coaxial cable for a balanced feedline. I've used it for years and it works supper.

Good Luck!
Bill
Jul 16th 2012, 01:03

KF7SXD

Joined: Dec 13th 2011, 23:51
Total Topics: 0
Total Posts: 0
Victory!
I recently decided to go through the effort to convert my invert L to a vertical wire up one of the trees at the top portion of our backyard. I had installed a quarter-wave radial for 20m, 40m, and 80m, and had moderate results. I was able to receive much more than I had previously, but transmitting was still a problem. I was able to get out enough that a late night net was almost able to hear me, but not enough above the background noise to checkin. Then I added one more radial and tried again. This time I was trying to check in to the net during a solar flare and through thunderstorms between myself and the net control. He was actually able to pick me up through all of the noise at about an S5. I've ordered a connecting plate for my radials to make it easier to attach more wires (right now I just have several wires connected to the ground post of my balun). Once the plate arrives, I'm going to do a better job of laying down at least 16 radials and get them stapled down. I'm confident this will greatly improve my system's performance.
Thanks folks. :-)

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