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Equipment List (will be adding to)


Doctnj
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So handhelds came in last night and had a fun time seeing how far they could reach half charged.  I could not wait till they were fully charged.  Most rechargeable batteries are shipped between 30 and 50 % at least in the drone world.  Way better than expected even though.  Almost 3 miles with rolling small hills and trees.  KG-805G and NA-771G on top.  Wife was still in the house and I was in my truck so pretty nice.

Now the rest of the plan.  ----- What is already on order    JetStream 25 Amp switching power supply.  Tram 1486, Kg-100G radio, and for mobile, NL-770g, Tram 1296 mno-UHF adapter, Br-1258 UHF 3/4 inch hole mnt, comes w 17 ft coax. 

 

                                          -----  What is about to be ordered   ROHN 28' MAST pushup, ROHN 24D WALL MOUNT, ROHN BASE, GROUND WIRE, GROUND ROD, GROUND WELD CLAMP, GOUNDING BAR, ALPHA DELTA UHF COAX SURGE PROTECTOR, GROUND COPPER WIRE,  COAX CONNECTOR WEATHER PROOFING TAPE,  ( not sold on guy wire etc ) since it goes up, it can come down or lower for storms.  Ill have to look at it, the mast is 28' max and I dont see going much past 20 if that.

For the coax Ill use will be the good stuff.  I need to do some measuring and figure out how many fittings I need plus 2 and how many feet of coax plus 5'

AND AN SWR METER  - but im not saying which one :)

So far for now.  Any suggestions excepts swr's welcomed                                       

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When trimming antenna, what results would say "don't go any further. 
I would probably use the high power channels as well as repeaters. Zach
Normally you can't trim commercial antennas that long. They are pretuned and colianear style antennas.

If let say a cb antenna, you read the bottom channel swr and top. Bottom is higher then top then usually too long (trim). If top is higher then bottom the (then too short, extend, If not possible stop immediately). You can't length many antennas without replacement of the whip.

Normally, I tune so the middle has the lowest. Remeber most vswr curves are v in shape.

When vswr starts climbing around where you were wanting the curve to be the lowest you stop.

Very important to go slow and small changes.

Many hams have piles of whips where they went to far and trimmed too much.

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When trimming antenna, what results would say "don't go any further. 
I would probably use the high power channels as well as repeaters. Zach

Honestly, the numbers you have received (1.03 and 1.5) are quite good that you have nothing to worry about. At 50 watt output power, your reflected power is a mere 2 watts. Some quality pre-tuned antennas are advertise to only be 1.7 or below and here you are down at 1.5.

If the antenna could be adjusted non-destructively (meaning no clipping) I would surely play with it as a learning exercise just to learn how I could squeeze more out of it. But if adjustments are destructive, I would probably stop when when numbers fell into the range you have unless I was prepared to purchase replacement should I accidentally go to far. If it was a collinear design, I would not mess with it at all because they are too complicated for DIY field adjustments.
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Here is the challenge with trimming.  The measurement starts at a coil. That alone is complicated as the measurement looks like it starts at the outside edge of the wire diameter just below the 85° bend. If the coil rotates then that length moves a little and angle changes to 90°. I had to measure in mm as I don't have any tapes that break down to 1/32".

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Here is the challenge with trimming.  The measurement starts at a coil. That alone is complicated as the measurement looks like it starts at the outside edge of the wire diameter just below the 85° bend. If the coil rotates then that length moves a little and angle changes to 90°. I had to measure in mm as I don't have any tapes that break down to 1/32".
16212517845881180201658277196213.thumb.jpg.d09ac2c95f5531c67c12628ad74d3255.jpg
Then leave good enough alone before you regret it.

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You have no idea of how happy I am to not trim anything again.  I didnt do any water proofing of the connector after it was screwed on and of course today its raining.  I will work on the grounding after work and after I make the final decision where the radio will sit I will put the final connector on.  woo hoo.  It was very nice to hear folks talking on a few different channels while I had the radio plugged in.  So seems to be more popular than expected.  There were on HP channel so I know they werent just frs. 

This may be a dumb question but can you run a tone between members of a group on a non rpt channel?

 

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You have no idea of how happy I am to not trim anything again.  I didnt do any water proofing of the connector after it was screwed on and of course today its raining.  I will work on the grounding after work and after I make the final decision where the radio will sit I will put the final connector on.  woo hoo.  It was very nice to hear folks talking on a few different channels while I had the radio plugged in.  So seems to be more popular than expected.  There were on HP channel so I know they werent just frs. 
This may be a dumb question but can you run a tone between members of a group on a non rpt channel?
 
Yes, you can.

Understand, everyone can hear you. You will not hear them if the tones do not match.

Think of it as a squelch that only opens when the tones match.

Now you know why everyone says the antenna is more important then the radio.

Uhf/vhf is mostly line of sight. The higher up you get it the more likely it is able to see other antennas over mountains and obstacles. Going from a 1/4 wave magnet mount on my truck to a 5/8 over 5/8 I went from 8-12miles to 23-40 miles. Going from a ht with the radio to my ftm400 now I can hit repeaters some 30 miles away easily. The x200 (8ft 2/70) 30+ feet in my attic. I am hitting repeaters close to 90 miles away (different band with ham repeaters).

Congrats. You are reaping the rewards of your work.

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11 minutes ago, kidphc said:

Yes, you can.

Understand, everyone can hear you. You will not hear them if the tones do not match.

Think of it as a squelch that only opens when the tones match.

Now you know why everyone says the antenna is more important then the radio.

Uhf/vhf is mostly line of sight. The higher up you get it the more likely it is able to see other antennas over mountains and obstacles. Going from a 1/4 wave magnet mount on my truck to a 5/8 over 5/8 I went from 8-12miles to 23-40 miles. Going from a ht with the radio to my ftm400 now I can hit repeaters some 30 miles away easily. The x200 (8ft 2/70) 30+ feet in my attic. I am hitting repeaters close to 90 miles away (different band with ham repeaters).

Congrats. You are reaping the rewards of your work.

Sent from my SM-G975U using Tapatalk

 

The reason I asked, there was a line of jeeps coming through town Sat and they were loud and clear so I knew they were close.  Then sure enough they passed right by me.  We have lots of trails in the Ozarks.  I keyed up and asked where they were from and no one even skipped a beat so I was pretty sure they were running a tone.  It is a really cool idea going to a trail where people are everywhere using the same channel.  

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The reason I asked, there was a line of jeeps coming through town Sat and they were loud and clear so I knew they were close.  Then sure enough they passed right by me.  We have lots of trails in the Ozarks.  I keyed up and asked where they were from and no one even skipped a beat so I was pretty sure they were running a tone.  It is a really cool idea going to a trail where people are everywhere using the same channel.  

If your radio has tone scan capability, you can easily use it to determine the code they are using so you can in-turn enter it in your radio and use it to converse back with them.


Michael
WRHS965
KE8PLM
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Well I came home to put the last attachment on so I could hook up the radio inside but kept getting continuity from shield to center conductor. I didn't take the time to waterproof last night and woke up to hard rain all day.  There has to be moisture in the top connection to the antenna because the run that goes into the house was fine after I disconnected it from the lightning arrestor.  I had already cut off and re did the inside attachment three times thinking I messed up the cable. But after testing all the way out I'm pretty sure the issue is up top, with water ingressed into the connector.  Just glad I didn't skip the continuity test and just turn on the radio. Bad news is, it's supposed to rain for a week. Note to self.... Check forecast. This is one of those "throw in the towel" nights. Worst case I'll bring it down and take antenna off and bring it in and dry out w dehumidifier. If it's not one thing it's your mother. I even had the seal wrap outside yesterday and skipped it to do today...... 

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I hate learning things the hard way.  Just checked and still dead short.  I'll be pulling the antenna and cable from arrestor up and bringing it in.  I hope this part will help others to not make the same mistakes.  I guess I should be able to used some compressed air to clear any water enough to test if there is a mechanical short and not liquid??? 

 

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I hate learning things the hard way.  Just checked and still dead short.  I'll be pulling the antenna and cable from arrestor up and bringing it in.  I hope this part will help others to not make the same mistakes.  I guess I should be able to used some compressed air to clear any water enough to test if there is a mechanical short and not liquid??? 
 
Could be a kink caused damage or excessive solder in one of the crimps. Guess you got to test each component individually.

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1 hour ago, kidphc said:

Could be a kink caused damage or excessive solder in one of the crimps. Guess you got to test each component individually.

Sent from my SM-G975U using Tapatalk
 

yes, Im going to take it all down and test everything again.  I was careful to have big gentle curves but who knows.  Hopefully I can figure out what the issue is.

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10 hours ago, Doctnj said:

yes, Im going to take it all down and test everything again.  I was careful to have big gentle curves but who knows.  Hopefully I can figure out what the issue is.

This is cable going into and out of outside box.  I got connector on the inside of house finally and at least that leg shows no continuity shield to center.  So the issue is the feed going up the antenna.  I'm going to bet it's up top. We had quite a lot of wind and rain yesterday. I have to order more connectors.  Because I destroyed two.... Those were the two 'extra'.  Just take a deep breath. Most valuable things in life I learned just like this. 

The feed into is hard to see but it's a really big loop to have reserve if I needed to go higher. 

Once I get everything clicking I'll inject foam into the wall to capture the cable insulate it. 

 

 

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16 minutes ago, mbrun said:

Do you already have your ground rod in somewhere that just cannot be seen in the pictures, or is that still to come?


Michael
WRHS965
KE8PLM

Now it's just out of the frame. It's there.  I haven't put the ground wire in yet in that picture though.  

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actually after I looked at the pictures on my laptop and not on my phone, yes the ground rod is in the picture.  I have the one shot connector,  connecting the outside box and antenna and mast to ground.  Right now until I get the antenna pulled down, hopefully today, and bring it inside and test from nose to tail.  Im just basically hoping that it will be clear that there was water ingress in the top connection. But the cable coming from the antenna is no longer hooked up to the feed into the house until I sort it out.

If it is indeed wet, would you recommend cutting the connector off and putting on a new one or just drying it really well then re install and weather proof?   Our extended forecast is rain pretty much every day for a week.  I have new connectors on order so no rush.  

Again I hope by making my install and errors in judgement public, others may learn.  

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I am highly skeptical that water is your issue. Skeptical because water, unless jam packed with minerals, will not manifest as a dead DC short. Since you have been reporting that you see a short when using a multimeter, that suggests to me that a physical metal-to-metal continuity exists. My initial guess is a strand of braid or perhaps even a sliver of the shield foil is making contact with the pin within the connector case, or your antenna.

I would remove the coax from the antenna and put the ohm meter directly across antenna’s connector (case to pin) to confirm if you have a DC short there. Some antennas (like a J-pole for example) have both poles of the antenna reference the same DC potential as an integral part of their design. The design of your antenna could similar.

If the antenna shows a DC short, the only way to know for certain if there is an issue with the antenna is to check its impedance. That will require a VNA or other form of antenna analyzer hooked directly to the antenna.

As far as your cable is concerned. Once the cable is disconnected from the antenna and open at both ends I would check for shorts. After confirming that a short really exists there, I would pick a suspect connector, cut if off, and immediately check again. If the short disappears, your instinct on the suspect end was correct, so replace the connector. If the short still exists, cut off the other end and once again immediately check for shorts. If you still have a short in the cable without connectors on, then there is an issue with the cable.

If you had an antenna analyzer, you could confirm whether you had an issue at all without having to take the antenna down. Oh, the wonder of modern electronics.

As a point of reference, when I measure the DC resistance of two different roll-up J-poles I have and use regularly, both measure .3 to .4 ohms DCR. When I measure the DC resistance of my Comet CA-712EFC it is Infinity.

Hope this helps.


Michael
WRHS965
KE8PLM

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Is this antenna dc grounded design? Most commercial verticals are. It would show up as a short, please some one correct me if I am wrong.

Plus, if it is a dc grounded antenna you may want to ground the mast.

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22 minutes ago, mbrun said:

I am highly skeptical that water is your issue. Skeptical because water, unless jam packed with minerals, will not manifest as a dead DC short. Since you have been reporting that you see a short when using a multimeter, that suggests to me that a physical metal-to-metal continuity exists. My initial guess is a strand of braid or perhaps even a sliver of the shield foil is making contact with the pin within the connector case, or your antenna.

I would remove the coax from the antenna and put the ohm meter directly across antenna’s connector (case to pin) to confirm if you have a DC short there. Some antennas (like a J-pole for example) have both poles of the antenna reference the same DC potential as an integral part of their design. The design of your antenna could similar.

If the antenna shows a DC short, the only way to know for certain if there is an issue with the antenna is to check its impedance. That will require a VNA or other form of antenna analyzer hooked directly to the antenna.

As far as your cable is concerned. Once the cable is disconnected from the antenna and open at both ends I would check for shorts. After confirming that a short really exists there, I would pick a suspect connector, cut if off, and immediately check again. If the short disappears, your instinct on the suspect end was correct, so replace the connector. If the short still exists, cut off the other end and once again immediately check for shorts. If you still have a short in the cable without connectors on, then there is an issue with the cable.

If you had an antenna analyzer, you could confirm whether you had an issue at all without having to take the antenna down. Oh, the wonder of modern electronics.

As a point of reference, when I measure the DC resistance of two different roll-up J-poles I have and use regularly, both measure .3 to .4 ohms DCR. When I measure the DC resistance of my Comet CA-712EFC it is Infinity.

Hope this helps.


Michael
WRHS965
KE8PLM

Yes both answers help a great deal.  I'll report back when I have the answer. 

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FWIW I picked up the shrink sleeves as well as three different kinds of elect tape when I started this project and I must say the scotch brand feels really good.  It stretches out nice and doesnt tear very easily at all.  It says UV resistant but at least for me my antenna is in a minimal sun area.   

 

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Here are the specs on the antenna.  It says DC ground construction in the list.  So if this is true Ive been worried for nothing.

  • UHF fiberglass base antenna
  • 5'3" (1.6m) tall
  • Single section
  • 5/8 wave 3 elements
  • 7" (19.5cm) radial length
  • 406-512MHz
  • 10MHz bandwidth
  • 6.5 dBd gain
  • Radiator and coil are hermetically sealed in fiberglass tubing for low SWR in all weather
  • DC ground construction allows static dissipation for low noise ratio and maximum lightning protection
  • Mast diameter accepted is 1 3/16" to 2 7/16" (30-62mm)
  • UHF (SO-239) connector
  • Max power 200 watts
  • 50 ohms
  • Maximum wind 135mph (60 m/sec)
  • Includes cutting chart
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16 minutes ago, kidphc said:

I know its a DC ground antenna as you get that typical "short 

Second, paragraph.

https://forums.radioreference.com/threads/swr-issue-on-dc-grounded-antenna.379423/

 

some more information:

DC Grounded Antennas - The Myth, The Legend, The Fantasy

https://www.iceradioproducts.com/80.html

Thankyou very much.  That explains a lot.  Well now I know what I have and what to do. 

In the past I've lost two projectors and two high dollar receivers in my media room.  Apparently HDMI ports are very susceptible to surge during a close ground strike even though our utilities are below ground. I now take the time to un plug them when possible during electrical storms. 

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