New Trig Radio, weird issues

[RFguy]

I'd be pretty sure the DCDC converter is making some of the noise

there is also right and wrong ways to use the ferrite clamps- they must be on the antenna coax cable at both near antenna end, and at the radio end just where it exits the instrument panel.  and you might need 4 to 6 in a row. Then Find the DCDC converter and put perhaps 6 ferrite clamps on input and output, but if its radiating directly from the device, that wont do anything.  It will have a DCDC converter in there, because the 14.4V constant voltage perfectly describes it being there.... 
The total noise - It could be the sum of many things. 

 

Edited October 12, 2023 by RFguy

[Blueadventures]

Any 5volt usb outlets in use? If so post images of where they are.

[shajen]

Blueadventures, I can get some photos organised next week, thanks

[shajen]

Blueadventures, I do have a 5v usb in the dash, but it doesn’t get used for anything.

RFguy, agree that’s it’s been a combination of a few things. I can order more ferrite clamps easy enough.  And will look for the DCDC connector.

[Blueadventures]

32 minutes ago, shajen said:

Blueadventures, I do have a 5v usb in the dash, but it doesn’t get used for anything.

RFguy, agree that’s it’s been a combination of a few things. I can order more ferrite clamps easy enough.  And will look for the DCDC connector.

Maybe disconnect that while you are trouble shooting; if fused just pull that fuse.

[shajen]

Ok!

[shajen]

Hi Guys,

this time I had a proper check of the voltages, not just the glance like last time. They are definately way too high! At 1000 rpm it’s on 14.4 without anything on, and then peaks at 15.8 when flying. When I got back down my friend put on a gauge to check if volt meter reading correctly. It is correct. 
He also checked the AC current, it was reading 30.3.  He didn’t think it should have been reading anything.

Spoke to my avionics guy, he thought it may be faulty regulator, perhaps still a bit of a grounding issue too. And at worst it may be a problem with the alternator. I hope not … that would mean the engine having to come out again! But I guess it should be a warranty issue. 
 

we noticed when flying that it does seem to cut in and out. Ocassionally we can actually hear, although most of the time not.

[Blueadventures]

Good info.  Not being familiar with Jabs I'll await experienced comment.  I have read that Jab 3300 Reg output is 14V + - (0.4V) so 13.2 to 14.8V.  Haven't seen any alternator output ac voltage info.  Hope this sheds light on your issue.

 

Also a ground run-in sheet for your engine needs to show AC volts at 2800rpm so this data and specs should be out there.

Edited October 18, 2023 by Blueadventures

[shajen]

Thanks Blueadventures!

[onetrack]

An alternator that is producing 15.8V is overcharging and has serious issues. It more than likely has a faulty voltage regulator.

 

An alternator should be peaking out at 14.8V, or 15V at the very absolute maximum. Any charging output from an alternator over 15V, will damage your battery and other sensitive electrics.

 

Get your alternator tested for correct operation before you go any further.

[facthunter]

I use 14.2 on lead acid batteries.  ( with adjustable regulators)..  A permanent magnet device is a Grim thing in principle as an electric power source.. Nev

[shajen]

I agree! Definitely overcharging!

 

Jabiru has said this could be because the yellow wire from the new regulator isn’t connected back to the battery. Causes the regulator to constantly increase the charge as it’s not being earthed correctly. (Or something along those lines, sorry I’m not up with electric stuff).  He said that may be causing the issues.  
 

This will be the next thing to check next time I’m at the aircraft. 

 

Trig has said there are no issues with the radio, didn’t think there would be, but it’s nice to have that eliminated.

 

I do hope if anyone else has a similar issue they might find something useful from all this😀

[RFguy]

yes indeed, the regulator has no voltage sense so it just thinks the battery is flat all the time

voltage sense wire must be connected. WHo did this work prior to you ????

 

Needs all the wires for the regulator connected. Jabiru's wiring is a bit F-ed up anyway, but it can be acceptable.

 

DO NOT fly or run it over 1500 RPM  with the regulator like that- you will damage ALL of your electrical systems and electronic instruments....

 

Regulator negative should go to the engine block which has a really good solid negative wire connection to the battery via the starter cables.

 

Regulator sense wire (usually yellow) needs to go to the battery via a 1 amp blade fuse.

 

Regulator charge output needs to go direct to the battery via a 20A blade fuse . There will be a tiny bit of current always drawn so it might flatten the battery over a couple of months. IDEALLY an extra relay (small cube headlamp relay will do it)  is required from the master , the relay goes in series with the alternator charge output  so when the master turns off, the regulator charge output is disconnected from the battery. 

 

and....Transient voltage suppressors or diodes need to be across the main bus to avoid the master relay back EMF damaging radios and electronics, as it does....

 

 

 

 

 

 

 

 

[shajen]

Glen, thanks for that!

I’ve done none of the work myself, all done by my L2 and another guy there who does avionics on RAAus aircraft.  I won’t mention where, but I don’t think that avionics man knew what he was doing.  I haven’t been back to him but am now using a guy from AY who is quite switched on. But he’s flat out and doesn’t go to Benalla. So that’s why I’m asking so many questions and trying to find people locally who can test stuff, 

But if I shouldn’t fly until I get this fixed, I’m stumped! I wouldn’t even know how to wire anything, let alone put a fuse in.

maybe I can find a friendly auto electrician around here.

will let you know how I get on🤞

[Blueadventures]

Is there a gliding club nearby, if so ask who does their maintenance work. They may assist.

[shajen]

Actually, that’s a great idea. There are heaps of gliders here!

thanks

[Blueadventures]

2 minutes ago, shajen said:

Actually, that’s a great idea. There are heaps of gliders here!

thanks

Some one there will be more than capable to hook up the yellow wire and fuse etc.

[RFguy]

Hi Jenny

well, if the 'avionics guy' didnt connect the battery sense wire, he either  was having a bad day, or needs to be sued, or the wire 'came off'.

So, I am sure there is more to this story. ANyway, get what I suggested done. If the headlamp relay doesnt have a 'flyback/reverse' diode across the coil, ensure that one gets put on.

No-----, if you fly with high voltage like that (The TRUE peak voltage is much higher than indicated) you'll damage everything connected to the 12V bus..... If not damaged now, you will reduce the life and things will die for no reason prematurely, even after it is all fixed up....

 

Use something like a :  - they have the diode in them. NARVA 68032 or 68032BL
NOTE THAT THESE UNLESS MOST RELAYS WILL HAVE + AND - ON COIL .  - to ground, + to 12V bus so relay turns on when master on

 

Repco Australia | Auto Parts Store - Aftermarket Car Parts

WWW.REPCO.COM.AU

 

 

Narva | 12V 40A NORMALLY OPEN 5 PIN RELAY WITH DIODE (BLISTER PACK OF 1)

WWW.NARVA.COM.AU

---

Narva relays are manufactured to exacting original equipment standards under the control of ISO9001.

or 

Narva | 12V 40A NORMALLY OPEN 5 PIN RELAY WITH DIODE

WWW.NARVA.COM.AU

---

Narva relays are manufactured to exacting original equipment standards under the control of ISO9001.

 

NARVA 68032 or 68032BL

 

[shajen]

Ok, will go shopping tomorrow! 
 

[shajen]

Hey Glen,

looking at the regulator wiring diagram from Jabiru, I’m a little confused. 
Jamie at Jabiru said the yellow should go direct to the positive on the battery via a 1amp fuse. But the diagram shows the yellow goes to the main bus and red goes to battery positive. 
Am I missing something?

[Tasmag]

2 hours ago, shajen said:

Hey Glen,

looking at the regulator wiring diagram from Jabiru, I’m a little confused. 
Jamie at Jabiru said the yellow should go direct to the positive on the battery via a 1amp fuse. But the diagram shows the yellow goes to the main bus and red goes to battery positive. 
Am I missing something?

It just depends on which regulator you have, the old ones go the the main bus, the new ones go direct to battery.

 

Mike

[shajen]

Ah ha! That answers that question, mine is new!

Thanks Mike

[Tasmag]

 Here are the instructions for the new regulator if that helps

Regulator 35A installation PI4A026N Issue 2.pdf

[RFguy]

Jabiru company aircraft wiring is... questionable. 

Battery sense should ALWAYS go to the battery (via small fuse)  NO MATTER WHAT. anyone who wants an argument, put $10,000 on the table and let's have a bet. Comon, I'll see you in court.

Battery charge should go to the battery to remove alternator 'noise' components from the wiring harness.  If the battery charge wire goes to the harness/master, then high frequnecy battery charge current 'noise' will fill  and pollute  the 12V bus .

Battery charge must go via a fuse (20A in this case) AND ideally,  via an isolation relay that is actuated from the master 12V bus. 

Battery negative SHOULD go to the negative battery terminal BUT engine block is good enough because starter cable size, direct to battery negative, is usually sufficiently sized to not have any voltage -current noise.

 

Jabiru factory wiring practice I beleive, may be responsible for Jabiru airframe fires. IE the need of a master battery contactor - because std Jab wiring puts UNFUSED battery B+ through the firewall. Where as good practice, and safe practice, and certainly all part91 cert aircraft, the battery is isolated at the battery via a contactor/relay which is turned on and off via a battery  master switch. This has been well covered by me here several times. 

 

 

 

Edited October 20, 2023 by RFguy

[shajen]

Ok, so I’ve got the fuses and relay. I could only get 5 amp blade fuse, not 1 amp.  Tomorrow Shane and I will do the following:

1 put the yellow wire from the regulator direct to positive on battery

2 ensure the earth wire is connected to engine block or the negative on the battery.

We still need to determine where the 20amp fuse needs to go and the isolator. I have some wiring diagrams downloaded that may help.

We will get these first two parts done anyway, and ask around the gliding people and see if anyone can help during the week!

Hopefully this is where most of the interference has been coming from.

Thanks again