Gauge noise on VHF radio

[TMitch]

ISSPro boost and EGT gauges are in and working great EXCEPT the EGT is causing VHF birdies all over the place s5-7. The noise is intermittent, comes and goes in bursts. The radio is a a Yaesu FT-2600. It is definitely the EGT, I put a switch in the lead powering the little circuit amplifier box and when I turn it off, noise goes away. I wrapped the little box in aluminum foil (hoping for an easy fix). That did nothing. Gauges are powered directly out of fuse panel. Radio is wired direct to battery.

Any ideas?

 

[FourBarR]

use shielded wire . i did all my gauge wiring with aircraft shielded wire. it prevents this kind of problem.

 

[DieselMinded]

"""" EGT, I put a switch in the lead powering the little circuit amplifier box""""



Do you have an electronic EGT sender or something????



It may be the TC lead wire ran next to your power wire for your Yaesu FT2600



wire ran close together will interfere with each other happens alot in car audio applications are you penitrating the firewall at the same place if so find another way threw the firewall for one of the wires.



DM

 

[TMitch]

DM - The ISSPro thermocouple wires run into a little box that then has wires that run up to the gauge and then a different set of wires for power. So that makes 3 sets of wires running in/out of the little box.

It is definitely the EGT that is causing the noise, verified by turning the power off.

Now the big question, I can only find one easy way through the firewall - the big rubber boot that the main wiring harness runs through.

Where else can I run wires through the firewall?



I will try to run the EGTwire away from the radio power wires and see if that makes a difference. Just thinking as I write this... I will bring a handheld VHF into the truck and see if it picks up the same interference, By moving it around in the cab I might be able to find the exact source of the noise. I will report back shortly.

Thanks for the help so far.

Terry

 

[WDaniels]

TMitch,

I have the Yaesue 2600 or the 2800 think its the 2600

and the Isspro guages with the same egt box and set up that you have. I don't have the noise problems that you have. Either with the Yeasue or my hand held radio. Then again I run in the freq range of 154 and above. Must be something else.

WD

 

[TMitch]

I finally remembered to take my handheld radio (Yaesu VX-150) out into the truck. Same problem with the handheld but not as bad, the mobile radio squacks all the time and the handheld radio does about half as often. I couldn't really find the source but it was worst near the dash . The source is definitely the ISSPro EGT gauge. When I turn off the power to the gauge, the radios stop squacking.

WDaniels - it occurs on several different frequencies between 140 and 170 MHz.

It's not coming in through the power leads to the radio because the handheld does it too. Thanks for the help, if I ever figure out how to fix it, I let everyone know.

Terry

 

[RonaldLarson]

Grounding?

Try changing your grounding scheme. Ground the sender and the gauge in exactly the same physical point.

Ron

 

[WDaniels]

Of course TMitch, the question is, what are you doing above 148mhz with a commercial ham radio, Hmmmmmmm??

WD

 

[JWChessell]

Listening.

 

[WDaniels]

Not above 148mhz he ain't.

WD

 

[HoleshotHolset]

Dad's Isspro EGT gauge setup makes enough racket that you can hear it without using an HT or mobile rig.



He's hard of hearing... so it doesn't bother him. I plowed snow with his truck for 12 or so hours and I wanted to rip that gauge/amplifier box right out of the pod... better judgement prevailed, however.



73's,



Matt

 

[Lnwing]

Dad's Isspro EGT gauge setup makes enough racket that you can hear it without using an HT or mobile rig.

Mine was the same way. It had a high pitched squeal that would drive you to distraction! I finally called Isspro"s tech line and found out that the noise was an issue on some of the early units. After some troubleshooting, they replaced it.

 

[WDaniels]

Ah ha! Thats what that extremely high pitched whine that I hear is. I mean it's way up there and you can barely hear it and only lasts for about 1 or 2 minutes max. It sounds like it comes from my boost gauge on the pillar. I have my egt box under the dash by the clutch pedal. But it doesn't interfere with my radios at all. Guess I'll keep an ear on it.

WD

 

[TMitch]

My Yaesu FT2600 has wide band receive (they come from the factory like that!). Most amateur radios do. My noise problem is isolated to receive only. I like to listen to marine weather up here and I also listen to the logging road channels when I am driving on the logging roads because you never know when a 200 ton off-highway logging truck is going to appear around the next corner. The log trucks call their miles so you always know when to find a pullout and get out of the way. The trucks have 16' wide log bunks and take up the whole road.

As a licenced amateur radio operator, my radio is, as installed, legal (it is only able to transmit between 144-148 MHz). In my company truck, I use a properly licenced Yaesu VX-3000 commercial radio.

By the way, I haven't solved the noise problem yet.

Everything is grounded in the same spot.

WDaniels where are you grounding everything and where did you run the wires for the radio and gauges through the firewall?

 

[WDaniels]

TMitch,

I have my radio hooked to a painless wiring harness and thread it through the firewall by the steering shaft. As a matter of fact, all my wires come through that hole. I get no interference from anything on my radio and I ride at 154. 010. I don't know what to tell you about your interference. It must be indigenous to your truck.

WD