ground loop in vehicles body/chassis. check grounds. Most common is the body to engine or ground. when this goes bad, anything grounded to the body will find its path home through, the spedo cable, or your coax shield!
The main thing I would say and I don't see in the comments where anybody else even seemed to notice it. But if I saw that right, your homes were somewhere around 70 or 80 and that's way too high. Your home should be balanced the same way your SW R's are. If you're at 1.1 or 1.0 on 20, your own should be 50 and then channel 1 and 40. Your home should be balanced the same number, though. It'll be a little bit higher, but just a few numbers. Not you know, down the street higher. I think that's the culprit , so that would wait me to go back to the coax
It may be the material that the roof is made off. You may also have a bad ground somewhere in your truck. Seems to me as a ground issue. You may have a bad factory ground somewhere in your truck. Check your alternator ground also you may want to check your fuel pump ground. Their is also a couple of grounds from the body to the frame. You may have a corroded ground strap connector.
The roof is sheet metal just like the rest of the truck. Something seems to have changed from when I first installed everything. Hopefully I'll be able to figure it out one day and share what it was. I think I'll remove the power wire, re-run it a different path and ground the amp directly at the chassis under the seat and go from there.
This is great video. Did you ever find out your issue? An SWR of 2.5 is supposed to be too high and can hurt your amp. I have similar demons in my setup. Everyone says SWRs shouldn’t change no matter the power but mine do!
Did you ever get this issue figured out? I am experiencing the same issue with TS 1600 and exact same meter. I run a RM Italy 503HD and all is good with reflection same as barefoot radio. Thanks
Desert Explorer, you still having problems with your radios ? Check your antenna again. Using your mfj 259, go to efficiency setting in advanced settings and see what your antenna efficiency is displaying. How much does your Texas Star 350 hdv push out in wattage ? Sounds like your radios are doing well. Billy / Albq. N.M. 1 / 4 / 2023
don't know if you got the problem solved, I have the same problem on mobile antennas but only on the lower bands such as 40 and 75 meters where the antenna resonates fine but when I power up the radio I get high SWR. The reason is that my car does not have enough of a ground plane for the lower bands. I have not had that problem on 20, 10 or 6 meters. If I take the same set up and move it from my car to my full size p/u truck I can do 40m fine but still not enough ground plane for 75m. I'd use a mag mount set up on the roof of your truck and see if it works...73 de KB1TCD
Update!!! So my buddy 191 comes over today. Galaxy 959 with a Texas Star 500 in his mobile. We put 2 different meters on his truck and guess what? Same exact reflect the same exact way! His mobile is louder then base stations around here. So He's running a Texas Star 500 and all 3 amps I tested in my mobile we're all Texas Stars so I'm now confident it's nothing to worry about and simply something within the texas star circuitry causing what must be a false reading. All 4 amps show normal and then step up to show reflective power the same exact way in two totally separate vehicles and using two different meters.
I have the same issue on a base with a Texas Star 350HDV and a Galaxy DX 2547. The 350 has original 2879's and I don't want to blow them. My Bird 43 swings backwards on RMS with the amp on. I don't know why and I don't like it at all. I cant figure it out either.
Hey, it's some thing to do with the trucks ECU THE TRUCK IS ODB II ?? Some how the ground side has a negative positive effect I hope some how it make's some kind of sense
Whenever I see something like this it is a grounding issue. Not that your equipment is not properly grounded. Your antenna does not have sufficient ground plane underneath the antenna(counterpoise). Remember as your power increases your ground plane needs to be able to support this added power. Your "Plane of ground" is sufficient for a barefoot radio; But when you add power everything goes haywire. You need to add more ground plane potential to the roof of your vehicle.
Have had similar issues and grounding was the culprit. Maybe grounding everything has caused some sort of ground loop? Try removing all the grounds minus the antenna being already grounded via roof and see if there’s a change. If not borrow another meter from someone. Meters can be flaky sometimes. Good luck and sure you will fix it. Let us know!
Put 102 inch stainless steel whip and by adding or taking away coax you can match the antenna to the radio and it will be a perfect match. but soon as you add in a meter in line that match goes off because you off set the length, the way I do it is you put in your linear and then put in your coax and make your adjustment by adding more or taken away in most cases you add length.
Remember the load coupling is based opon ..the carrier load... If u rurn the load up to set the vswr setting ..then tirn it down everything from that setting is wrong.... Were unset the couple is were u uave to keep the carriwr load to have a consistent reading...u cant load and set then cut back the load...if u do the set mean nothjng anymore...hope this makes since
Its unclear to me if you tried putting the meter between the amp and radio to check what thats doing. Another thing the comes to my mind is make a 1:1 balun at the antenna foot and try what that does. Most simple way to to that is a ugly coax balun. You could try it for test. Another thing is perhaps you have created a unwanted ground loop. You connected the amp to ground. Did you try already to remove the amp from any ground. Does that shows other readings? If so you could ground the amp with a ground wire to experimental to the antenna foot check it again. Then move the amp ground to the radio ground and check again. Just experimental to see if something changes.
Maybe the same problem I've been having in my cargo van, too big of a ground plane. Try moving the antenna toward the front or all the way toward the back. Maybe I'm just guessing
Everything looks normal my only concern is the amps heatsink buried in the carpet. I mount all my transistor amps upside down with fans on them. "If it ain't broke don't fix it"
@@vegasfordguy Heatsink mounted fans work best to dissipate large amounts of heat from the finals. Your just blowing hot air around inside the cabinet. That method works ok for a radio with no heatsink.
@@miguelsalami It works just fine for this little amp. It never heats up much anyway. It's not just blowing air around, it's actually forcing in, over the components and then back out. It actually works quite well for this little 2 pill.
@@miguelsalami Don't know, don't try to abuse my amps, however I have no problem having a long conversation while cruising down the road. You won't even catch me trying to see how long I can key down my base amp with 4 high flow fans on it. Just because I could, doesn't mean it's a good idea. What about Stereo's, factory amplifiers, etc that are crammed behind the dash? They heat up and usually last for the life of the vehicle. This little amp has forced air cooling and stays quite cool. Although it's not ideal how it's mounted, it stays cool.
It really doesn't matter much, I've done it both ways. I don't even bother closing the door anymore. Think about what's going on as you're driving down the road. The antenna is swaying all over, you're driving under trees, bridges, next to buildings, other vehicles, etc.
Its the Meter Ive had numerous problems with my MFJ 870 false readings goes out of calibration. try another meter these 870's are faulty. Thats an Export rig your overdriving the amp that causes back swing oversaturation of the pills maybe?
I am no tech whatsoever but I had the same problem. Would it end up being was I burned out the wire in the coax going back to my Ant ohm it out all them could be burnt
80 Ohms, should be 50... theres your problem! 00:08 took me 8 seconds to see that.. Prob bad coax.. i ll comtinue the video now! oh to get PROPER PEP, the meter has to be Powerd! is there connection on the back to add power cord.. and is that power just for the light?? alot of these cheap meters dont show proper PEP as they arnt powerd
1. The SWR must be set with the Amp ON! 2. Your testing with the doors open and close to houses. 3. Amp on test with meter set at the hundred watt scale for reflection!!
You would think so with everything you read, however in real life it make little to no difference at all. After checking SWR on numerous vehicles over the years it's basically a non issue. Check your SWR while driving down the road and you'll see why.
ground loop in vehicles body/chassis. check grounds. Most common is the body to engine or ground. when this goes bad, anything grounded to the body will find its path home through, the spedo cable, or your coax shield!
The main thing I would say and I don't see in the comments where anybody else even seemed to notice it. But if I saw that right, your homes were somewhere around 70 or 80 and that's way too high. Your home should be balanced the same way your SW R's are. If you're at 1.1 or 1.0 on 20, your own should be 50 and then channel 1 and 40. Your home should be balanced the same number, though. It'll be a little bit higher, but just a few numbers. Not you know, down the street higher. I think that's the culprit , so that would wait me to go back to the coax
Sounds like a ground issue. Do you have any straps, bed to cab and both to the frame?
It may be the material that the roof is made off. You may also have a bad ground somewhere in your truck. Seems to me as a ground issue. You may have a bad factory ground somewhere in your truck. Check your alternator ground also you may want to check your fuel pump ground. Their is also a couple of grounds from the body to the frame. You may have a corroded ground strap connector.
The roof is sheet metal just like the rest of the truck. Something seems to have changed from when I first installed everything. Hopefully I'll be able to figure it out one day and share what it was. I think I'll remove the power wire, re-run it a different path and ground the amp directly at the chassis under the seat and go from there.
This is great video. Did you ever find out your issue? An SWR of 2.5 is supposed to be too high and can hurt your amp. I have similar demons in my setup. Everyone says SWRs shouldn’t change no matter the power but mine do!
Idk .the only thing I would do any different is If I was using the 300 watt scale for forward power I would use the same scale for reverse .
Did you ever get this issue figured out? I am experiencing the same issue with TS 1600 and exact same meter. I run a RM Italy 503HD and all is good with reflection same as barefoot radio. Thanks
Desert Explorer, you still having problems with your radios ? Check your antenna again. Using your mfj 259, go to efficiency setting in advanced settings and see what your antenna efficiency is displaying. How much does your Texas Star 350 hdv push out in wattage ? Sounds like your radios are doing well. Billy / Albq. N.M. 1 / 4 / 2023
don't know if you got the problem solved, I have the same problem on mobile antennas but only on the lower bands such as 40 and 75 meters where the antenna resonates fine but when I power up the radio I get high SWR. The reason is that my car does not have enough of a ground plane for the lower bands. I have not had that problem on 20, 10 or 6 meters. If I take the same set up and move it from my car to my full size p/u truck I can do 40m fine but still not enough ground plane for 75m.
I'd use a mag mount set up on the roof of your truck and see if it works...73 de KB1TCD
Update!!! So my buddy 191 comes over today. Galaxy 959 with a Texas Star 500 in his mobile. We put 2 different meters on his truck and guess what? Same exact reflect the same exact way! His mobile is louder then base stations around here. So He's running a Texas Star 500 and all 3 amps I tested in my mobile we're all Texas Stars so I'm now confident it's nothing to worry about and simply something within the texas star circuitry causing what must be a false reading. All 4 amps show normal and then step up to show reflective power the same exact way in two totally separate vehicles and using two different meters.
I have the same issue on a base with a Texas Star 350HDV and a Galaxy DX 2547. The 350 has original 2879's and I don't want to blow them. My Bird 43 swings backwards on RMS with the amp on. I don't know why and I don't like it at all. I cant figure it out either.
Hey, it's some thing to do with the trucks ECU THE TRUCK IS ODB II ??
Some how the ground side has a negative positive effect I hope some how it make's some kind of sense
Whenever I see something like this it is a grounding issue. Not that your equipment is not properly grounded. Your antenna does not have sufficient ground plane underneath the antenna(counterpoise). Remember as your power increases your ground plane needs to be able to support this added power. Your "Plane of ground" is sufficient for a barefoot radio; But when you add power everything goes haywire. You need to add more ground plane potential to the roof of your vehicle.
Have had similar issues and grounding was the culprit. Maybe grounding everything has caused some sort of ground loop? Try removing all the grounds minus the antenna being already grounded via roof and see if there’s a change. If not borrow another meter from someone. Meters can be flaky sometimes. Good luck and sure you will fix it. Let us know!
I am having this exact same issue were you ever able to figure anything else out or correct the issue? I'm very interested in any remedies
Put 102 inch stainless steel whip and by adding or taking away coax you can match the antenna to the radio and it will be a perfect match. but soon as you add in a meter in line that match goes off because you off set the length, the way I do it is you put in your linear and then put in your coax and make your adjustment by adding more or taken away in most cases you add length.
Remember the load coupling is based opon ..the carrier load... If u rurn the load up to set the vswr setting ..then tirn it down everything from that setting is wrong.... Were unset the couple is were u uave to keep the carriwr load to have a consistent reading...u cant load and set then cut back the load...if u do the set mean nothjng anymore...hope this makes since
Its unclear to me if you tried putting the meter between the amp and radio to check what thats doing. Another thing the comes to my mind is make a 1:1 balun at the antenna foot and try what that does. Most simple way to to that is a ugly coax balun. You could try it for test. Another thing is perhaps you have created a unwanted ground loop. You connected the amp to ground. Did you try already to remove the amp from any ground. Does that shows other readings? If so you could ground the amp with a ground wire to experimental to the antenna foot check it again. Then move the amp ground to the radio ground and check again. Just experimental to see if something changes.
Balun choke 1:1 is the way
Try running Amp with green am button pushed in Texas star recommends this it will make a difference in the tune
Maybe the same problem I've been having in my cargo van, too big of a ground plane. Try moving the antenna toward the front or all the way toward the back. Maybe I'm just guessing
Body to frame ground issue maybe?
I might be grasping at straws here but is your jump between radio and amp tuned?
Everything looks normal my only concern is the amps heatsink buried in the carpet. I mount all my transistor amps upside down with fans on them. "If it ain't broke don't fix it"
You're right about the heat sink, however this amp has a forced me air fan on the top cover with vent holes. That's why I mounted it this way.
@@vegasfordguy Heatsink mounted fans work best to dissipate large amounts of heat from the finals. Your just blowing hot air around inside the cabinet. That method works ok for a radio with no heatsink.
@@miguelsalami It works just fine for this little amp. It never heats up much anyway. It's not just blowing air around, it's actually forcing in, over the components and then back out. It actually works quite well for this little 2 pill.
@@vegasfordguy How long do you think you could keep it keyed down for without it overheating?
@@miguelsalami Don't know, don't try to abuse my amps, however I have no problem having a long conversation while cruising down the road. You won't even catch me trying to see how long I can key down my base amp with 4 high flow fans on it. Just because I could, doesn't mean it's a good idea. What about Stereo's, factory amplifiers, etc that are crammed behind the dash? They heat up and usually last for the life of the vehicle. This little amp has forced air cooling and stays quite cool. Although it's not ideal how it's mounted, it stays cool.
Are you doing your test with the doors of your vehicle open? If so, try doing it with the doors closed and your car away from any obstruction.
It really doesn't matter much, I've done it both ways. I don't even bother closing the door anymore. Think about what's going on as you're driving down the road. The antenna is swaying all over, you're driving under trees, bridges, next to buildings, other vehicles, etc.
I had a similar issue I was using a thru the body mount on my trunk with the same Sirio 5000 and turned out to be a bad mount
Have you tried to reset the swrs with everything in line
Its the Meter Ive had numerous problems with my MFJ 870 false readings goes out of calibration.
try another meter these 870's are faulty. Thats an Export rig your overdriving the amp
that causes back swing oversaturation of the pills maybe?
Try,shortest jumper. Amp too meter. Avoiding falls readings.
I am no tech whatsoever but I had the same problem. Would it end up being was I burned out the wire in the coax going back to my Ant ohm it out all them could be burnt
Burnt two amplifiers up because of it brand brand new coax was bad then I started burning antennas up
Hopefully you got it fixed
Check the swr from your rig to the amp.
You also could have a bad diode in the meter ..but not teal common
Well this is late but use some flat braid and bond everything to the frame
80 Ohms, should be 50... theres your problem! 00:08 took me 8 seconds to see that.. Prob bad coax.. i ll comtinue the video now! oh to get PROPER PEP, the meter has to be Powerd! is there connection on the back to add power cord.. and is that power just for the light?? alot of these cheap meters dont show proper PEP as they arnt powerd
1. The SWR must be set with the Amp ON! 2. Your testing with the doors open and close to houses. 3. Amp on test with meter set at the hundred watt scale for reflection!!
You would think so with everything you read, however in real life it make little to no difference at all. After checking SWR on numerous vehicles over the years it's basically a non issue. Check your SWR while driving down the road and you'll see why.
@@vegasfordguy I'm just trying to help. It's been a year I hope you figured it out.
Try the amp on low or medium stage see if it moves
You might have to bond your grounds to each other and I'm really sure that you won't have that problem after you 😉 bond those grounds together
Some meters will show RMS AS REFLECT.
You've ruled out any possibilities so I don't know what to say
Jumper jumper jumper jumper jumper jumper jumper jumper jumeper...and or the mount and bracket ... Its in the feedline
I wanna see just the radio on a average watt meter
U git to be using proper freq.. spec for coupling and this is the reason
Huh?
It must be for 30 mhz range is al I'm saying
Get that coil above the roof rack
Could be impedance match.
Check all your ground wires you have a ground issue
I have, checked all for continuity.
That meter is not for 27 MHz it is not ACB meter
The meters you useusy be for proper frequency...its that simple
It's definitely for the proper frequency.
Look at the megahertz of that meter it's not for CB
Lol, 1.6-60. CB is 27mhz. You are 100% wrong.
Ferrites at the antenna feed point and thank me later.
I'll almost bet it's that rack
Try another meter…
The coax going from meter to antenna. Your last run of coax. Make it shorter and see if the reflect comes down......
Add A COMMON MODE CHOKE. mfj-915 THERE 302