Problems with my 2M install

[mountainpete]

Hi all,

So I installed my new Yaesu FT-8800R and I am having an issue...

When the truck is turned off, the radio has crystal clear send/recieve. When the truck is turned on, the receive audio is crackly and gets worse at higher RPMs. It gets really bad on some frequencies - but it's not high pitched like most alternator noises are on radios. It's very crackly.

I'm sure I'm not the first person to have an issue like this and I wouldn't doubt that it is something just bad with my install. Any best first things to do or look at?

I installed it very simply for the time being as I didn't have a long enough antenna to put the transmitter body behind the rear seats. The radio is basically connected directly to the battery and on a temp mount under the drivers seat.

Thanks!

Pete

 

[Scenic WonderRunner]

Pete........

Do you have a Toyota..........>?

I've read that it's a "Toyota Issue".........with the Fuel Pump.

The fuel pump makes an electronic noise that creeps into your radio.

I don't know the fix........

I just know this fuel pump noise happens!

I have noise on my CB Radio.....and I think it's the same thing!

Good Luck!

 

[DaveInDenver]

Well, it's sort of obvious that it's related to the engine. Duh, huh? There are two obvious sources of interference generated by the engine, the alternator and the ignition. Some things come to mind.

Are you using non-stock spark plugs and/or wires? Changing to non-suppression wires is a huge source of interference. The stock wires are resistance (usually called carbon conductor) type and they are used largely to reduce interference, while the wound type hi-pro ones can cause problems, particularly with CB and ham radios. If they are at all noise suppressed and/or tested for RFI it'd probably only be on the AM & FM broadcast bands.

The alternator could have a bad diode or is just simply a source of RFI. There's not much you can do to eliminate altenator noise from being generated, so you just need to shield things and route things to minimize the chance it gets into your radio. Ferrite beads can help if it's coming in on the power and being sure to ground the coax shield if it's coming in through the antenna feed.

Some good things to do are to wire both postive and negative straight to the battery. Don't ground the negative near the radio, run both wires all the way to the battery. Also twisting them can help decrease common mode noise, if it's being radiated into the power leads. Be sure the coax is not running parallel to any power leads or computer lines. If they cross, make sure they cross at a right angle and run parallel as little as possible. Things like the power to the fuel pump can be huge noise sources, too. I have an EFI truck, but don't seem to have a problem with either the CB or the ham from the fuel pump. I do get some ignition noise when my wires start to get old (I run stock wires, replaced about every 2 years). Putting a cap across the fuel pump (as close to the pump as possible, since I know pulling the pump from the tank is not really an option) can reduce that interference.

Try rerouting the feedline and power leads, taking care to keep them away from existing wiring. Be sure to trim them to the right length and don't coil them into circles. Ferrite beads can work at the computer and other controllers, too. Be sure the connector on the coax is making good contact and the connectors are not corroded at all. Be sure the antenna mount is grounded and the antenna itself is tuned to produce a SWR lower than about 3:1 across the whole band.

 

[Grim Reaper]

Dave covered power issues and issues with ignition components so I will try to cover other sources.

Since it varies with RPM you can rule out the fuel pump. They are on or off and always run basically the same RPM.

I am not failure with the component location in your vehicle but in mine I have several engine related modules under the dash that drag in ignition noise off the Tach feeds for the ECM and cruise control....even the A/C has a tach feed that will shut off the A/C if the idle is too low.

In my instance my issue is I run the antenna on the hood for best ground plane (86 4Runner with removable fiberglass top and a glass sunroof so larges ground plan is the hood). The antenna feed is running parallel to the FI harness where I went through the firewall. I will need to relocate the to come out through the inner fender/kick panel with the radio antenna and route it up under the cowl to get away from the harness.

More then likely your noise is coming in off the antenna lead. Best thing you can do is try to route the antenna wire away from any of the vehicle harnesses and ECM's. If its running down the door threshold check for vehicle harness there. Tuck the wire farther up under the carpet.

BE CAREFUL OF WHERE THE CAT IS. I use to run a cell phone install shop and I was all the time finding coax that heat from the cat caused the internal insulation to melt. Avoid routing the cable directly over where the CAT is located.

Second think to check is where the control modules are in relation to where the radio is mounted. It is not uncommon for modules to be mounted in the dash over the hump.

Power wires can also be a source but most manufactures are pretty good about putting filters and chokes on the power inputs so I would worry about that last but if all else fails Dave hit it on the head...go to the battery and see if it cleares check the alternator. If you want to check something simple make sure that if you wired it switched to put the trigger wire to an accessory trigger like the radio or the Cig lighter. Avoid catching power off anything that would be engine related.

Another thing to be aware of is excess antenna lead. DO NOT COIL THE EXCESS. A coil of wire makes and inductive pick up. It amplifies the noise. If you have excess you need to make open loops (zig zags that don't overlap).

Don't kink the wire either. Coax and Radio Frequency is a funny animal. Coax is best described as a "wave guide". The signal travels ON the center wire. The outer weave is a shield that keeps that signal on the the center conductor. If the distance between the center conductor and the shield changes (kinked wire, smashed wire, melted insulation) it will cause a restriction in the flow of the signal. The Shield has to have a good connection to ground to be the most effective. If your antenna is mounted off something that is insulated you may need to run a ground strap from the mount to the body. Especialy if the cable is long.

 

[HenryJ]

Oregon Dept. of Transportation vehicles and our district fleet use a heavy duty power supply filter from RadioShack for those vehicles with bad power source noise.

Part# 270-0055 20A DLX Noise Filter $19.99

It is not a cure-all but does help in some instances. I am running one on my truck to help with the alternator interference.

 

[DaveInDenver]

I've heard that the Radio Shack noise filter has been discontinued. Dunno if that's true or not, but each time I go into a RS it seems they have fewer and fewer radio items, so it wouldn't surprise me.

Anyway, you can also build your own filter, it's nothing fancy. A good one is a Pi filter:

C1 = 1uF electrolytic
C2 = 4700uF electrolytic
L1 = 1uH

Use all 16V or higher caps and current is really limited by the size of L1.

 

[PCRover]

Here is a filter you can try for a reasonable price.

Alternator Whine Filter

and another one...

Another Filter

 

[mountainpete]

Thanks guys!

I'm going to go though all your recommendations - I think I will try the filter as a last resort.

First, I have decided to totally change the way I am wiring it. I'm at work right now (and I'm up to my armpits!) I'll post more details later.

In the meantime, one question... On a battery with side posts and top posts, do you think it would of any extra value to wire the radio to the side posts instead of to the top posts like everything else is?

Thanks!

Pete

 

[PCRover]

The only real value is you remove the clutter of another set of wires on the top posts. Electrically it makes no difference.

 

[asteffes]

Thanks guys!

I'm going to go though all your recommendations - I think I will try the filter as a last resort.

First, I have decided to totally change the way I am wiring it. I'm at work right now (and I'm up to my armpits!) I'll post more details later.

In the meantime, one question... On a battery with side posts and top posts, do you think it would of any extra value to wire the radio to the side posts instead of to the top posts like everything else is?

Thanks!

Pete

Run one hefty wire from a side terminal to a distribution block with fuses for each terminal. Put the filter on the feedline to the distribution block so all your toys can enjoy clean power.

 

[mountainpete]

Thanks guys!

Ok... this is what I am planning to do this weekend if I can find the right fuse block in time:

1) Connect a heavy gauge power and ground wire directly to the battery. I will be using something from the local car audio shop - probably the generic version of a Monster Cable. I will try and wire both of these from the side posts of the battery instead of the main.

2) I am going to twist the power and ground together and run them inside of a plastic covering through the engine bay and along the drivers side of the frame rail and up through one of the floor gromets in the rear of the doublecab. Note - the antenna cable is also running in the same area - is the is problem?

3) Next, I am going to wire it to a small fuse block which I will mount behind the rear seat. Hoping to pick out a fuse block this weekend - it will probably be something from either the marine or audio store. At most it will be 4 fuses - one for the radio, one for my cell phone booster and two extras for future electronics.

4) I am then going to re-mount my radio behind the rear seat (it is currently under the drivers seat on a temp mount as my antenna cable wasn't long enough.

First, I will try it without a filter, if I still get the noise I will buy one.

I am concerned about one thing though - I have never mounted anything on the rear wall of the cab behind the seats. I did put my cell phone booster back there, but since it was so light I was able to just use industrial velcro to hold it to the carpet. What's the best way to mount the fuse block? Isn't it just a single layer of steel on the back? I don't want to drill or screw right through!

Thanks for all your help!

Pete

 

[mountainpete]

bump - any thoughts gang? :shakin:

 

[asteffes]

Thanks guys!

Ok... this is what I am planning to do this weekend if I can find the right fuse block in time:

1) Connect a heavy gauge power and ground wire directly to the battery. I will be using something from the local car audio shop - probably the generic version of a Monster Cable. I will try and wire both of these from the side posts of the battery instead of the main.

Remember to fuse the positive side near the battery so you'll be protected from the cables shorting between the battery and distribution block. A 30-40 amp fuse is probably appropriate for most needs. Even better might be a resettable circuit breaker. I would run 8 or even 6 gauge cable so you don't end up re-running heavier cable later. Just do it right and do it once.

2) I am going to twist the power and ground together and run them inside of a plastic covering through the engine bay and along the drivers side of the frame rail and up through one of the floor gromets in the rear of the doublecab. Note - the antenna cable is also running in the same area - is the is problem?

Running the coax near the power might introduce some noise. I have not run it that way before, so I can't say for sure. What grade coax are you using?

3) Next, I am going to wire it to a small fuse block which I will mount behind the rear seat. Hoping to pick out a fuse block this weekend - it will probably be something from either the marine or audio store. At most it will be 4 fuses - one for the radio, one for my cell phone booster and two extras for future electronics.

Don't be afraid to get a block with more fuses than you need today. It probably doesn't cost much more and you might like to have it down the road.

4) I am then going to re-mount my radio behind the rear seat (it is currently under the drivers seat on a temp mount as my antenna cable wasn't long enough.

First, I will try it without a filter, if I still get the noise I will buy one.

I am concerned about one thing though - I have never mounted anything on the rear wall of the cab behind the seats. I did put my cell phone booster back there, but since it was so light I was able to just use industrial velcro to hold it to the carpet. What's the best way to mount the fuse block? Isn't it just a single layer of steel on the back? I don't want to drill or screw right through!

Some industrial strength mounting tape will probably suit your fuse block fine.

Thanks for all your help!

Pete

 

[asteffes]

Thanks guys!

Ok... this is what I am planning to do this weekend if I can find the right fuse block in time:

1) Connect a heavy gauge power and ground wire directly to the battery. I will be using something from the local car audio shop - probably the generic version of a Monster Cable. I will try and wire both of these from the side posts of the battery instead of the main.

Remember to fuse the positive side near the battery so you'll be protected from the cables shorting between the battery and distribution block. A 30-40 amp fuse is probably appropriate for most needs. Even better might be a resettable circuit breaker. I would run 8 or even 6 gauge cable so you don't end up re-running heavier cable later. Just do it right and do it once.

2) I am going to twist the power and ground together and run them inside of a plastic covering through the engine bay and along the drivers side of the frame rail and up through one of the floor gromets in the rear of the doublecab. Note - the antenna cable is also running in the same area - is the is problem?

Running the coax near the power might introduce some noise. I have not run it that way before, so I can't say for sure. What grade coax are you using?

3) Next, I am going to wire it to a small fuse block which I will mount behind the rear seat. Hoping to pick out a fuse block this weekend - it will probably be something from either the marine or audio store. At most it will be 4 fuses - one for the radio, one for my cell phone booster and two extras for future electronics.

Don't be afraid to get a block with more fuses than you need today. It probably doesn't cost much more and you might like to have it down the road.

4) I am then going to re-mount my radio behind the rear seat (it is currently under the drivers seat on a temp mount as my antenna cable wasn't long enough.

First, I will try it without a filter, if I still get the noise I will buy one.

I am concerned about one thing though - I have never mounted anything on the rear wall of the cab behind the seats. I did put my cell phone booster back there, but since it was so light I was able to just use industrial velcro to hold it to the carpet. What's the best way to mount the fuse block? Isn't it just a single layer of steel on the back? I don't want to drill or screw right through!

Some industrial strength mounting tape will probably suit your fuse block fine.

Thanks for all your help!

Pete