Help Troubleshoot our Radio

E.Hagle

Well-Known Member
Joined
Mar 5, 2020
Posts
502
RDC Crypto
848
Location
Somis, CA
Our alumicraft class 10 has had issues with radio transmission outbound to chase trucks since day one. “Engine noise” overpowers driver and corider trying to get a message out. When the car is off everything is crystal clear. PCI has looked at the car in their shop a few times, same answer, “Alumicraft must have wired something oddly”. Alumicraft has had the car many times and says the wiring is the same as any other car. They even brought in an outside guy to look at it.

Point being, no one can fix our issue. It’s very frustrating. We just got a new to us RPS prerunner with all of the same equipment and it works flawless.

We have the Kenwood line filter as well. Have looked for oddities like weird grounds. Alternator interference. Everything we can throw at it.

Please help
 

McCredie A

Well-Known Member
Joined
Jan 29, 2008
Posts
832
RDC Crypto
440
Location
Vista or Hemet, Ca
Our alumicraft class 10 has had issues with radio transmission outbound to chase trucks since day one. “Engine noise” overpowers driver and corider trying to get a message out. When the car is off everything is crystal clear. PCI has looked at the car in their shop a few times, same answer, “Alumicraft must have wired something oddly”. Alumicraft has had the car many times and says the wiring is the same as any other car. They even brought in an outside guy to look at it.

Point being, no one can fix our issue. It’s very frustrating. We just got a new to us RPS prerunner with all of the same equipment and it works flawless.

We have the Kenwood line filter as well. Have looked for oddities like weird grounds. Alternator interference. Everything we can throw at it.

Please help
You might want to let Palomar communications take a look. He has hooked me up a few times on my old alumicraft prerunner. It worked great after he tuned it. Very knowledgeable.
 

SMS81

Well-Known Member
Joined
Jan 16, 2008
Posts
361
RDC Crypto
447
Location
CA
Make sure radio lines run separated from engine lines. Radio lines will pick up interference from other cables, particularly fluctuating power charging lines. Also make sure the radio and intercom are using their own individual power supply and chassis grounds. Good luck.
 

jon coleman

Well-Known Member
Joined
Jan 17, 2019
Posts
10,884
RDC Crypto
6,584
Location
sandiego
heavy gauge wire Directly to battery, in its Own loom,insulated, Away from any other possibility of eng electronics/ wiring looms/ harnesses& away from other wires up under the ' dash' too, at Any radio component, intercom, area ect .it got mine real nice & quiet
 

E.Hagle

Well-Known Member
Joined
Mar 5, 2020
Posts
502
RDC Crypto
848
Location
Somis, CA
You might want to let Palomar communications take a look. He has hooked me up a few times on my old alumicraft prerunner. It worked great after he tuned it. Very knowledgeable.
Palomar was the guy that alumicraft brought in. He made improvements but the majority of the issue is still present.
 

E.Hagle

Well-Known Member
Joined
Mar 5, 2020
Posts
502
RDC Crypto
848
Location
Somis, CA
Sounds like I’ll have to go at this myself and spend a few days on the wiring. Not looking forward to it.
 

btshannon

Well-Known Member
Joined
May 17, 2002
Posts
746
RDC Crypto
397
Location
The Yuccs, Ca. 92284
Maybe try broadcasting with the alternator belt off? It could help narrow down where the problem is?
 

partybarge_pilot

Well-Known Member
Joined
Feb 19, 2002
Posts
6,787
RDC Crypto
1,623
Location
Easton, KS
Some PCI intercoms are set up to run the ground through the radio. Pull the ground off the intercom and see if it still works. Ground loop is the most common issue with those.

Antenna cable, cut to length or excess coiled up somewhere making a nice inductor?
 

jon coleman

Well-Known Member
Joined
Jan 17, 2019
Posts
10,884
RDC Crypto
6,584
Location
sandiego
yup, hmmm, 'just coil up antenna wire excess& zipp tie it to the Metal roll cage, along side the main wire harness'( sarcasm😬
 

daenow

New Member
Joined
Oct 3, 2021
Posts
2
RDC Crypto
1
Location
escondido
Our alumicraft class 10 has had issues with radio transmission outbound to chase trucks since day one. “Engine noise” overpowers driver and corider trying to get a message out. When the car is off everything is crystal clear. PCI has looked at the car in their shop a few times, same answer, “Alumicraft must have wired something oddly”. Alumicraft has had the car many times and says the wiring is the same as any other car. They even brought in an outside guy to look at it.

Point being, no one can fix our issue. It’s very frustrating. We just got a new to us RPS prerunner with all of the same equipment and it works flawless.

We have the Kenwood line filter as well. Have looked for oddities like weird grounds. Alternator interference. Everything we can throw at it.

Please help
let me know if you need help still. i am a radio tech for fire departments and have been branching out to race. i am in escondido and completly mobile. let me know david 760 8556298
 

dzrt performance

Well-Known Member
Joined
Jan 31, 2014
Posts
166
RDC Crypto
107
if your radio system works normally with the engine OFF....this proves you have a ground issue. doesn't have to be the radio.

does the engine and or alternator have ground straps on them?

people refer to the chassis connection as "ground". IT ISN'T. ground is the negative side of the battery. you are using the chassis as a conductor...once again...it isn't ground. The point being, various tabs or welded studs used for ground connections ARE NOT equal....in terms of "resistance" back to the battery negative terminal. This is where the ground loop comes from and is what is causing the alternator whine in your system.

could be a simple matter of paint or grease or whatever interfering with your ground connection and it doesn't have to be the radio. more than likely its coming from the engine not be grounded properly OR the connection point (or any other connection point) does not have an equal unimpeded path back to battery negative.

you can test ground points with a multi-meter set on resistance (ohms). measure with one probe DIRECTLY on the battery negative terminal, then measure all your other ground points. all should be less than one ohm. anything higher will create a ground loop that causes the whine.
 

green787

Well-Known Member
Joined
Jan 2, 2005
Posts
10,926
RDC Crypto
2,698
Location
Southern, CA.
Website
realsound.us
Some PCI intercoms are set up to run the ground through the radio. Pull the ground off the intercom and see if it still works. Ground loop is the most common issue with those.
Yes, lift the black wire.....That's what fixed my engine noise in the system.... perfectly quiet now...
 
Top