Ham Radio Install Intermittent Power Issue

[TNTACO]

Hi All,



I need a little help. I recently installed my Icom 7000 in my 2024 Ford Bronco. Everything is working fine. I have made several contacts on HF and there is no noise or RF on my signal, and I am not hearing any ignition noise or anything on the receive side either. I am actually very surprised how clean it is as I had to do extensive grounding when I had this installed in my 2015 Ford F-150. Here is the only problem I am having. I am getting an intermittent recycling of the power when transmitting. I checked the SWR on the meter of the radio and it is below 1.5. It does not happen all the time. I can't isolate it to when I am sitting still verses driving down the road. It sometimes cuts out as soon as I key the mic and then sometimes it is in the middle of a transmission. Here is the setup I have for reference.


Radio head mounted on dash

Body of radio mounted in cargo storage area under the floor. I have it grounded back there to the body.

12-volt direct line from the battery to radio. Fused on positive and negative. Grounded to chassis, not the battery. I also have a noise suppression kit on the positive side.

UHF/VHF antenna is a Comet CA-2X4SR. Mounted near the front driver side A post

HF antenna is a Little Tarheel II mounted on the spare tire carrier where it bolts to the back door. I used the existing bolts with a custom mount I made.

Antenna is grounded to the back door and the body in the rear.

I have a choke on the feed line as it enters the rear door

I have a Tunematic TM-1 auto tuner connected to it and mounted with the radio.

The controller for the Tunematic is in the back for now but will be routed to the front over the auxiliary switches.

The microphone is mounted neat the front dash.



I have well over 30 hours in this installation, so I am all in and not quitting now. Any help would be greatly appreciated.

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[Brian_B]

Could be a problem internal to the radio, but a few things to check first:

First I’d try a different ground location. Probably even going so far as to take a ground straight back to the battery, even if it’s only temporary for testing.

Make sure the connection on your fuses are good and tight and don’t have any interfering cable insulation - especially set screws and/or crimps

Also try replacing the fuse - make sure it’s the proper fuse for the carrier and is good and tight in there.

Make sure the power and ground leads to the radio are good.

I’d also eliminate the fuse on the ground - not necessary in my opinion and and not providing any protection beyond what the fuse on the positive side does - and just another point that could be causing issues

Consider wiring a 12V meter right on the power leads to the radio - could be temporary with a Fluke, or a permanent display. That could help troubleshoot this issue.

 

[CalvinT]

I’d also eliminate the fuse on the ground - not necessary in my opinion and and not providing any protection beyond what the fuse on the positive side does - and just another point that could be causing issues

I agree. All fuses act as a small resistor. That is why they can get hot enough to blow. This means your ground isn't a true ground with the fuse in it. So there's noise on it. When you key up, the increased current draw causes more noise on your ground wire.

You don't describe exactly what you mean by recycling of power. If you mean the radio reboots, it could be a software problem in the radio or it could be caused by noise on the ground caused by the fuse.

 

[CalvinT]

Thinking a bit more. You should run a new ground wire. Even the connectors add resistance to your ground bath.

 

[GnormalGnome]

If the radio itself isn't the problem (overheating, etc.), it's almost always going to be a grounding issue.

As mentioned, there is no need for a fuse on the negative side. There's also a lot of aluminum on the Bronco, so double/triple check all connections, especially that tailgate ground.

I'd make myself a test wire either straight to battery negative or to the actual chassis/frame and use that as a replacement ground to test each connection one at a time.

Less likely to be the cause, but you might also consider taking the noise suppressor and tunematic out of the loop to make sure the issue is isolated to the radio circuit.

Good Luck!

 

[Brian_B]

There's also a lot of aluminum on the Bronco, so double/triple check all connections, especially that tailgate ground.

Oh I didn't even catch that, yeah, someone else tried to ground something through the tailgate - an air compressor I think, and the tailgate is a horrible ground. Even the factory runs their grounds back to the rear fender chassis from the tailgate stuff.

 

[TNTACO]

Thank you very much. This is helpful. When I first hooked it up, it was cutting out on me, when I stopped. I finally realized that it was due to the Autostart. I turned that off and problem solved. But now it is intermittent so I know that is not the problem. I also thought maybe it mattered which positive terminal I connected to on the battery but my research shows it does not matter. Thanks again

I agree. All fuses act as a small resistor. This means your ground isn't a true ground with the fuse in it. So there's noise on it. When you key up, the increased current draw causes more noise on your ground wire.

You don't describe exactly what you mean by recycling of power. If you mean the radio reboots, it could be a software problem in the radio or it could be caused by noise on the ground caused by the fuse.

By cycling, I mean the radio shuts off and then comes back on again. That includes the Tunematic autotuner. I am going to eliminate the fuse on the negative and run it to the battery. That one is easy.

 

[TNTACO]

Regarding the tail gate grounding, i ran a ground from the antenna, and looped a connection to the tailgate and through to the body. I also found a ground wire in my inline fuses that was only holding by less than half the strands. That said, I ordered a new inline blade fuse holder for the positive and ran the ground directly to the battery and eliminated the fuse on the negative side. Thanks everyone for their help. Great suggestions by all. I will let you know how I make out.

 

[CalvinT]

By cycling, I mean the radio shuts off and then comes back on again. That includes the Tunematic autotuner.

So this could be your radio reinitializing and not power cycling. Everything now days has microprocessors. It could be a defect in the radio, or noisy ground. Either can cause your radio to reboot.

Since it sometimes happens in the middle of a transmission instead of when you key to talk, it may be heat related. It really is hard to tell. It may help if you keep a log of failures. Things to consider are time of day, outside temps, time the radio has been on, how many transmissions you've made and how long between them. If no pattern appears, they I'd suspect a defective radio probably with a microprocessor related problem.

You might want to put a temperature probe next to your radio and see if you see any connection to temperature.

 

[Shadow24]

Ran into this similar issue with my ICOM 400 when I installed an inline device to auto on and off the radio. The device was set to auto off as voltage reached a certain level. Try turning on your battery gauge and watch how much it fluctuates under normal driving conditions. I was going down the road and my radio would shut off. Ford insists this is standard and anything from 13.1 to 15.1 is OK.

 

[Shadow24]

Correction to my previous post. Ford said dropping to 12.3 and up to 15.1 was normal. My automatic power device dropped at 12.7. This happened infrequently but did happen and was annoying as the radio shut off and then would come back on.

 

[TNTACO]

Hi All,



I need a little help. I recently installed my Icom 7000 in my 2024 Ford Bronco. Everything is working fine. I have made several contacts on HF and there is no noise or RF on my signal, and I am not hearing any ignition noise or anything on the receive side either. I am actually very surprised how clean it is as I had to do extensive grounding when I had this installed in my 2015 Ford F-150. Here is the only problem I am having. I am getting an intermittent recycling of the power when transmitting. I checked the SWR on the meter of the radio and it is below 1.5. It does not happen all the time. I can't isolate it to when I am sitting still verses driving down the road. It sometimes cuts out as soon as I key the mic and then sometimes it is in the middle of a transmission. Here is the setup I have for reference.


Radio head mounted on dash

Body of radio mounted in cargo storage area under the floor. I have it grounded back there to the body.

12-volt direct line from the battery to radio. Fused on positive and negative. Grounded to chassis, not the battery. I also have a noise suppression kit on the positive side.

UHF/VHF antenna is a Comet CA-2X4SR. Mounted near the front driver side A post

HF antenna is a Little Tarheel II mounted on the spare tire carrier where it bolts to the back door. I used the existing bolts with a custom mount I made.

Antenna is grounded to the back door and the body in the rear.

I have a choke on the feed line as it enters the rear door

I have a Tunematic TM-1 auto tuner connected to it and mounted with the radio.

The controller for the Tunematic is in the back for now but will be routed to the front over the auxiliary switches.

The microphone is mounted neat the front dash.



I have well over 30 hours in this installation, so I am all in and not quitting now. Any help would be greatly appreciated.

As a follow up to this thread, I have resolved the issue. I found a ground wire on one of the connections that goes into the inline fuse assembly that was only held by half the strands. I also eliminated the inline fuse on the ground side and went directly to the battery. I had some redundancy built into this and have inline fuses right at the radio body in the back. That said, everything is working correctly, and my signal is solid from all reports. I had to do extensive grounding when I had this setup in my F-150. I was very surprised that I have little noise on receive and none on transmit. I am going to ground the exhaust to the body and the hood to the body. It is not hard to do and I think it will improve things as well. Thanks to everyone that participated in this thread. All of the ideas were solid and helped me diagnose things quickly. Hope to talk to you on the HF bands.

N3CRS, Scott

 

[Brian_B]

Ford said dropping to 12.3 and up to 15.1 was normal.

Matches my experience as well - normal for Bronco and the AGM battery

 

[Hunterwjusmc]

I also had an IC-7000 running mobile and I had the exact same problem. It is definitely a voltage issue. If the alternator is spinning at cruising rpm the voltage stays high enough. When you are at idle and the rpm of the alternator is low the power drag from keying up the radio will cause the voltage to drop just enough to cycle the power in the radio. I ended up putting a huge capacitor on the power to the radio. Btw, this is the same thing people with big audio amps do to keep the voltage up when the power draw from a big bass beat tries to pull down the voltage.

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