CB Gods hate me .... Ebay LMR 400 is no good?

[niceguy71]

The octagon shaped flat spots are needed to assemble the connector and are not an issue. I’m not sure anything is “wrong” with those connectors, it’s just everything compounded.

I may have missed it, but does the LMR spin when connected to the antenna or just the sweep gear?

I don't remember myself... so I'll check it this week... I know I hand tightened it then put a small pair of channel lock pliers on it to give it a little ummmp so it wouldn't come off... then I put the Coax Seal on it ( big mistake ...what a pain taking it off)

 

[niceguy71]

I don't remember myself... so I'll check it this week... I know I hand tightened it then put a small pair of channel lock pliers on it to give it a little ummmp so it wouldn't come off... then I put the Coax Seal on it ( big mistake ...what a pain taking it off)

if you look at this picture you will see the screw threads or barrel is MUCH SHORTER on the LMR400 than any other Coax cable I have

 

[RFI-EMI-GUY]

Do you have a regular analog VSWR meter? Does your radio have the VSWR feature built in? If so use one of those to check VSWR against the Rig Expert. It seems obvious that a mechanical problem is afoot here. Part of the problem is that Rig Expert has decided to recess the connector into the plastic housing. Your 90 degree adaptor might mate though.

 

[lynnsnyder1968]

I don't remember myself... so I'll check it this week... I know I hand tightened it then put a small pair of channel lock pliers on it to give it a little ummmp so it wouldn't come off... then I put the Coax Seal on it ( big mistake ...what a pain taking it off)

Wrap the connector with a layer of electrical tape then put the coax seal over it. Be sure to cover all the tape with the sealer.
I read that here somewhere...

 

[RFI-EMI-GUY]

Wrap the connector with a layer of electrical tape then put the coax seal over it. Be sure to cover all the tape with the sealer.
I read that here somewhere...

Oh god no. That wont fix a loose electrical connection...

 

[lynnsnyder1968]

Oh god no. That wont fix a loose electrical connection...

Not for the connection but so you can get the sealer off easier, I should have said that.
Here is the thread.

 

[niceguy71]

Do you have a regular analog VSWR meter? Does your radio have the VSWR feature built in? If so use one of those to check VSWR against the Rig Expert. It seems obvious that a mechanical problem is afoot here. Part of the problem is that Rig Expert has decided to recess the connector into the plastic housing. Your 90 degree adaptor might mate though.

no I have a bunch of pictures of my RigExpert connected to the 90 Degree Elbow and it spins in circles ....the Elbow is a cheap product from Amazon..... so the sawtooth on the SO239 never engage onto the RigExpert..... but as I said most of my antenna coaxes works great with the RigExpert.. like the Tram3500 screw on fine ( the Tram 3500 has that long barrel... ) my RG8 has the long barrel and it also screws on just fine and works well.... I am thinking the E-bay seller used cheap connectors.... let me see if if my LMR400 tightly connects to the Antenna ... if it does I have to cut ther other end off anyway to make a straight run into a hinged plastic box where it will go into my Lightning arrestor.

 

[niceguy71]

Oh god no. That wont fix a loose electrical connection...

Do you have a regular analog VSWR meter? Does your radio have the VSWR feature built in? If so use one of those to check VSWR against the Rig Expert. It seems obvious that a mechanical problem is afoot here. Part of the problem is that Rig Expert has decided to recess the connector into the plastic housing. Your 90 degree adaptor might mate though.

I have a 1985 Dosy PM 1000 TS it acts up sometimes??? it's getting old and I've set a couple hundred peoples antenna's with it over the years.... but it does seem to work sometimes.... I could try it..... I can take a handheld and the dosy out to the fence and see if it works.
https://www.ebay.com/itm/1146701255...P1uJ5q0HsKsui4BZnsuwfBdiY=|tkp:Bk9SR6DavPvOYg

 

[mmckenna]

if you look at this picture you will see the screw threads or barrel is MUCH SHORTER on the LMR400 than any other Coax cable I have

Don't get hung up on that part. Just different connector designs. The longer center pin the RG-8 is just the crimp/solder on those types of connectors.
The LMR-400 connector center pin length looks fine also.

Don't go cutting connectors off and replacing them.

You'll quickly get yourself into trouble if you start using the scatter gun approach to fixing this. You'll start changing so many different things that you'll end up spending a lot of money you don't need to and often never figure out exactly what the issue is. One of my early mentors taught me that. Don't fall into that trap.

You need to sectionalize/isolate the faults. Work ONE at a time and rule out individual components until you find the issue.

One thing you need to be able to trust is your test equipment. If you have any questions about the test equipment you are using, you need to stop and sort that out first. There's no point in swapping out connectors/parts/components if you don't know if you can trust your test gear.

First thing I'd do is get rid of the 90º connector on your tester. I've had more of those things go bad than I'd care to admit.

Start by connecting the 50Ω load directly to the RigExpert (do not use the 90º adapter) and see what it shows. Directly connecting the 50Ω load to the tester should show low SWR. If it doesn't, then you need to suspect the tester or the 50Ω load. You can check the load with a multimeter and confirm that it shows something close to 50Ω as an easy test for that.

You already said earlier that you connected the LMR-400 to the tester and connected the 50Ω load to the end of the coax, and it tested OK. You also said you checked for continuity/shorts and it tested OK. I think that tells you that the LMR-400 and its connectors are OK. Do the same test with the RG-8. It should look similar.


I'd also run the RigExpert to your mobile antenna since you said that was working OK and showing low SWR. Do that, and then compare it to the analog SWR meter and see if they show similar. They should. If not, you've got another issue to sort out.


Not saying I know what the issue is, just trying to point out the importance of testing each individual part on its own and sectionalizing everything.

While it's good to have a lot of us looking at this, it also can lead to confusion with too many people tossing out ideas. I think you have some mostly excellent advice above. Just try to focus on one thing at a time, proof out each part individually.

I think if one of us was there to help, we'd be able to help you find the fault rather quickly. Maybe taking prcguy up on his offer to visit would be worth the wait, worth the dinner, and worth the 6 pack of beer. He'll have the tools, test equipment and knowledge to solve this quickly on site without all the noise of internet posts in the way.

 

[niceguy71]

all fixed?????
ok I have a small 18" CHEAP coax cable I use for testing... it is a very cheap cable but it seems to work.... one end is a elbow and one is straight.... the elbow fitting will not fit on my Rigexpert.... it is loose and spins.... but the other end has the long pin and long barrel.... so I put that on the RigExpert and it tightens up nicely and I even have a couple threads still showing on the RigExpert ....on the other side I put a barrel connector which goes all the way into the elbow tightly and should make a great connection.. so this will from now on always be on my RigExpert ..... if that doesn't throw off my reading?????? will it throw off my reading????? I also tried various straight connectors on my LMR400 and they all fit tight.... so if this little 18" or 2 foot jumper doesn't hurt my SWR readings I should be all fixed and I will put my LMR400 on the Antenna then on a 21 foot pole and lean it up against a shed and see if the antenna is getting a decent SWR and hopefully that means it will work....... any problems with my purposed test??????

 

[niceguy71]

Don't get hung up on that part. Just different connector designs. The longer center pin the RG-8 is just the crimp/solder on those types of connectors.
The LMR-400 connector center pin length looks fine also.

Don't go cutting connectors off and replacing them.

You'll quickly get yourself into trouble if you start using the scatter gun approach to fixing this. You'll start changing so many different things that you'll end up spending a lot of money you don't need to and often never figure out exactly what the issue is. One of my early mentors taught me that. Don't fall into that trap.

You need to sectionalize/isolate the faults. Work ONE at a time and rule out individual components until you find the issue.

One thing you need to be able to trust is your test equipment. If you have any questions about the test equipment you are using, you need to stop and sort that out first. There's no point in swapping out connectors/parts/components if you don't know if you can trust your test gear.

First thing I'd do is get rid of the 90º connector on your tester. I've had more of those things go bad than I'd care to admit.

Start by connecting the 50Ω load directly to the RigExpert (do not use the 90º adapter) and see what it shows. Directly connecting the 50Ω load to the tester should show low SWR. If it doesn't, then you need to suspect the tester or the 50Ω load. You can check the load with a multimeter and confirm that it shows something close to 50Ω as an easy test for that.

You already said earlier that you connected the LMR-400 to the tester and connected the 50Ω load to the end of the coax, and it tested OK. You also said you checked for continuity/shorts and it tested OK. I think that tells you that the LMR-400 and its connectors are OK. Do the same test with the RG-8. It should look similar.


I'd also run the RigExpert to your mobile antenna since you said that was working OK and showing low SWR. Do that, and then compare it to the analog SWR meter and see if they show similar. They should. If not, you've got another issue to sort out.


Not saying I know what the issue is, just trying to point out the importance of testing each individual part on its own and sectionalizing everything.

While it's good to have a lot of us looking at this, it also can lead to confusion with too many people tossing out ideas. I think you have some mostly excellent advice above. Just try to focus on one thing at a time, proof out each part individually.

I think if one of us was there to help, we'd be able to help you find the fault rather quickly. Maybe taking prcguy up on his offer to visit would be worth the wait, worth the dinner, and worth the 6 pack of beer. He'll have the tools, test equipment and knowledge to solve this quickly on site without all the noise of internet posts in the way.

Great advice as always MMCkenna
....I am thinking it is the RigExpert where it has short threads???? I just took it apart again and pushed the plastic all the way down until it touched the base of the connector.... I tried to put it back together that way but it is not meant to go that way??? so with the plastic housing pushed tight against the base of the connector even then the threads were a little short... I don't know why they made it like that or if someone changed the connector (I got it used) .... but if you see my post before this one I think I have a work around that will do the trick. let me know what you think as I am going to the next phase when I get time.

 

[mmckenna]

I think your work around is a good solution. Give it a try.

 

[G7RUX]

RigExpert is good... it just doesn't let the connector tighten correctly.. but still makes contact and so far has always done a nice job for me ( I had it 2 weeks) ..my Tram 3500 cable and my RG8 both thread on normally and both give me a nice SWR

Ah OK. I had understood that the connector in the top of the unit was rotating!
I shall go back to standby…

 

[Ubbe]

That RG8 connector are soldered. You strip the coax and then insert the center lead into the center pin, that are attached to the plastic, and solder it in place. The LMR400 connector are crimped. You strip the coax exactly to a diagram that you get with the connector, or download, and then you crimp the center pin, that are loose and separate from the connector, on the coax and then you stick the whole coax and pin into the connector. When you do not follow the diagram exactly you can get the center pin to not fully go thru the connector, it usually clicks into place, this could be the case here, or the braid doesn't make a good contact with the body of the connector.

You can buy a $2 PL259 solder connector where you solder both the center pin and braid, and replace the one, or both, on the LMR400.
But if you can tighten the connectors at both antenna and radio side so they mate as they should and you can't twist them then the center pin will make a good connection and it should be ok. It's just the RigExpert that has a connector that isn't protruding far enough from the plastic cover.

/Ubbe

 

[niceguy71]

That RG8 connector are soldered. You strip the coax and then insert the center lead into the center pin, that are attached to the plastic, and solder it in place. The LMR400 connector are crimped. You strip the coax exactly to a diagram that you get with the connector, or download, and then you crimp the center pin, that are loose and separate from the connector, on the coax and then you stick the whole coax and pin into the connector. When you do not follow the diagram exactly you can get the center pin to not fully go thru the connector, it usually clicks into place, this could be the case here, or the braid doesn't make a good contact with the body of the connector.

You can buy a $2 PL259 solder connector where you solder both the center pin and braid, and replace the one, or both, on the LMR400.
But if you can tighten the connectors at both antenna and radio side so they mate as they should and you can't twist them then the center pin will make a good connection and it should be ok. It's just the RigExpert that has a connector that isn't protruding far enough from the plastic cover.

/Ubbe

I think the ends will work... they are not as good as a soldered ends in my opinion but I think they will work... I'll check it this week hopefully ( I run a small plumbing business and September I clean heating systems)... I have over 30 to do this week if I can.. it takes me 2 to 3 hours a system to clean it and tune it up ...I'm very thorough so I have about 90 hours of work to do this week... thank God I retired... I used to do this and worked another full time job... I'll keep everyone informed

 

[niceguy71]

ok the base antenna is up!!!!!! FINALLY!!!!
hello guys.... I always appreciate your help and I've needed a lot of it the last few months.... but I've got my base antenna up.. I still have to figure out how to mount my CB I'll either do the computer monitor arm to the side of the work bench so I can swing it out of the way when working in my garage...or hang it from the 2nd floor joists 12 feet above. ( going to need a lot of chain)
the Shakespeare Big Stick is dead. I cut it up and did an autopsy on it... I could not find anything wrong with it. it looked brand new inside but I had to cut it apart to see .... so I cut it into 1 foot pieces and put it in the trash... may it rest in pieces.
I tightened the LMR on the Big Stick tightly with pliers... when I cut open that area it did show the glue pulled away and the two wires touching. but I'm pretty sure I hit it with the sawzall so no way to tell... if it did move when I tightened it, it only moved a 1/16 of an inch. and these wires were more than that... see picture.
I bought a new Antron 99 with ground plane kit ( ($169 at Amazon) I loved the camo job PRCGUY did on his antenna, so I tried to do a little thing like that... it really doesn't stick out to bad I took a picture of it from the front of the house and you can hardly see it... heck you can hardly see it from the back ( all woods out back anyway.... it is gray blue and white... the color of New England skies. I mounted it to the fence I had the Shakespeare Big Stick on... put the SWR meter on it and presto 1.1 to 1.5 ....so finally something went right... I didn't adjust it as it was only a few feet from the metal fence and I thought it would change when I got it up in the air. .... as it turns out it didn't change one bit so I wished I had adjusted it, but it's perfectly fine.
it is 30 feet above the ground or 47 to the tip.... I turned it on and WOW I could hear people talking that I've never heard before and all the back ground noise was gone... it's amazing! I tried to get a LSB contact for a few hours tonight but couldn't.... I did get a Iowa contact in my pick up truck this morning 1000 miles away and I was doing 65 on the highway at the time!
ok one question....
on the fence and on my 30 foot mast I used my Rig Expert and got 1.1 to 1.5 using just the LMR 400.... while it was on the fence for a few weeks I ran my 100 foot RG8 into the garage to play with it.... putting the Rig Expert on it I got 1.1 to 1.3??????? then when we mounted it to the side of the house I again hooked it up to the Rig Expert just to the LMR 400 and again got 1.1 to 1.5????? tonight I ran my RG8 to it to play a little again and again with the RG8 it is 1.1 to 1.3 see pictures... so why is adding a 100 feet of RG8 dropping my SWR.... and you know what.... forget it I don't even care... I must have Magic RG8

 

[niceguy71]

ok the base antenna is up!!!!!! FINALLY!!!!
hello guys.... I always appreciate your help and I've needed a lot of it the last few months.... but I've got my base antenna up.. I still have to figure out how to mount my CB I'll either do the computer monitor arm to the side of the work bench so I can swing it out of the way when working in my garage...or hang it from the 2nd floor joists 12 feet above. ( going to need a lot of chain)
the Shakespeare Big Stick is dead. I cut it up and did an autopsy on it... I could not find anything wrong with it. it looked brand new inside but I had to cut it apart to see .... so I cut it into 1 foot pieces and put it in the trash... may it rest in pieces.
I tightened the LMR on the Big Stick tightly with pliers... when I cut open that area it did show the glue pulled away and the two wires touching. but I'm pretty sure I hit it with the sawzall so no way to tell... if it did move when I tightened it, it only moved a 1/16 of an inch. and these wires were more than that... see picture.
I bought a new Antron 99 with ground plane kit ( ($169 at Amazon) I loved the camo job PRCGUY did on his antenna, so I tried to do a little thing like that... it really doesn't stick out to bad I took a picture of it from the front of the house and you can hardly see it... heck you can hardly see it from the back ( all woods out back anyway.... it is gray blue and white... the color of New England skies. I mounted it to the fence I had the Shakespeare Big Stick on... put the SWR meter on it and presto 1.1 to 1.5 ....so finally something went right... I didn't adjust it as it was only a few feet from the metal fence and I thought it would change when I got it up in the air. .... as it turns out it didn't change one bit so I wished I had adjusted it, but it's perfectly fine.
it is 30 feet above the ground or 47 to the tip.... I turned it on and WOW I could hear people talking that I've never heard before and all the back ground noise was gone... it's amazing! I tried to get a LSB contact for a few hours tonight but couldn't.... I did get a Iowa contact in my pick up truck this morning 1000 miles away and I was doing 65 on the highway at the time!
ok one question....
on the fence and on my 30 foot mast I used my Rig Expert and got 1.1 to 1.5 using just the LMR 400.... while it was on the fence for a few weeks I ran my 100 foot RG8 into the garage to play with it.... putting the Rig Expert on it I got 1.1 to 1.3??????? then when we mounted it to the side of the house I again hooked it up to the Rig Expert just to the LMR 400 and again got 1.1 to 1.5????? tonight I ran my RG8 to it to play a little again and again with the RG8 it is 1.1 to 1.3 see pictures... so why is adding a 100 feet of RG8 dropping my SWR.... and you know what.... forget it I don't even care... I must have Magic RG8

 

[mmckenna]

ok one question....
on the fence and on my 30 foot mast I used my Rig Expert and got 1.1 to 1.5 using just the LMR 400.... while it was on the fence for a few weeks I ran my 100 foot RG8 into the garage to play with it.... putting the Rig Expert on it I got 1.1 to 1.3??????? then when we mounted it to the side of the house I again hooked it up to the Rig Expert just to the LMR 400 and again got 1.1 to 1.5????? tonight I ran my RG8 to it to play a little again and again with the RG8 it is 1.1 to 1.3 see pictures... so why is adding a 100 feet of RG8 dropping my SWR.... and you know what.... forget it I don't even care... I must have Magic RG8

There is more loss in the RG-8 than there is in the LMR-400, so the amount of power reflected from the antenna gets reduced. With the LMR-400, there is less loss, so more of the same reflected power makes it back to the meter.

The LMR 400 is getting MORE power to the antenna when you transmit. It's getting you MORE signal to the radio on receive. That is a good thing and exactly what you want.

Sounds like everything is working well now. Sounds like you have a good setup. Enjoy!

 

[RFI-EMI-GUY]

Glad to hear you have gotten it on the air finally! That Big Stick must have been haunted or a flaky PITA. My first CB station was a simple 1/4 wave groundplane. No problems, worked great.

My only comment, you should bond your antenna mast and surge protector ground rod to your building ground . As that appears to be an outbuilding, it probably has a subpanel with ground rod, and you can get your ground there hopefully.

 

[niceguy71]

Glad to hear you have gotten it on the air finally! That Big Stick must have been haunted or a flaky PITA. My first CB station was a simple 1/4 wave groundplane. No problems, worked great.

My only comment, you should bond your antenna mast and surge protector ground rod to your building ground . As that appears to be an outbuilding, it probably has a subpanel with ground rod, and you can get your ground there hopefully.

thanks RFI-EMI-GUY no that's the back of the house... if I could run a underground ground wire to the front of the house to the ground rod I would........ but it would be a huge ordeal to do... it's all rocks and boulders here... I also have tons of underground wires for sprinklers and two other buildings and motion lights here and there and underground propane lines..... a ditch witch couldn't do it 26 years ago.. I had to get a large excavator to make most of the trenches... we worked for a couple days to get the CB mast ground rod in last week.... we tried making a hole with a post hole digger and filling it with water and then using a HUGE powerful rotory jack hammer on top of the ground rod... nope day two we got a back hoe over and kept pulling 2 foot boulders out... we had to pretty much just keep pulling boulders out so we could get the ground rod in.... going around the house I would have to go 90 feet to the side... then 30 feet to the front yard then 80 feet to get towards the house ground rod.... the septic tank is in front of it and they had so much trouble digging it in that the tank is almost level with the lawn so getting a wire past that would be another issue.... my sprinkler pipe is only an inch deep, best they could do... so anything I do is going to rip apart all kinds of stuff......... I have a neighbor 10 houses down .... he has a dozen towers in his yard.... it's amazing to see... I want to take pictures but don't want him seeing me standing in front of his house.... he has wires running from one tower to another tower.. he has antenna's all over the ground.... from every tree... and his towers I don't even want to guess... 80 feet maybe higher??? biggest I've ever seen.... I stopped by to see if he could help me with my big Stick problem... thought he would have test equipment and knowledge.... I felt funny but knocked on the door... he wasn't too happy to see a stranger at first... he came to the door with a walker... all his stuff was put up 40 years ago his wife was in a hospice bed in the kitchen... I felt like scum.. but after chatting for 20 minutes I think he was enjoying telling me about his stuff.... the main tower has a 12 foot deep concrete base! ... so I asked about his grounding... do each tower have their own how did you tie them all together? ... he looked at me like I was crazy and said he doesn't have any ground rods and they don't connect to his house ground or each other... NO GROUNDS?????? so I asked how many times he has been hit by lightning?? he said in 40 years just once three years ago ... the lightning hit the neighbors tree and went underground and did a lot of damage to the neighbor's house and electronics.... but he was pretty lucky... he lost two radio's and that was it????? so my little 30 foot mast .... I'm not going to worry... I did call my insurance guy... he said not to worry I'm covered... he said in the 70's 80's everyone had a TV antennas on the roof.. and it's going that way again!... so he said not to worry I'll only have to pay the deductable.....my mast is only a few feet above my roof peak like a TV antenna and it's grounded the best I can do.
. I do appreciate the help and concern... but I'm going to hope for the best.... here is a picture of my septic tank in front of my electric meter.... the cover is in the middle of my 90 foot walkway and as you can see it is not very deep... my underground electric by code should be minimum of 18 inches... but I highly doubt it.... everything they did here took a lot longer to do and they were getting frustrated with anything that had to be dug...