radio interference

[Ennine]

Originally Posted by Duotone

You cannot use a rectifier on a DC input voltage.

A rectifier only works on an AC input and provides a DC output.

Dave T

Surely a diode (rectifier) will pass DC happily. In fact its characteristic will allow it to only pass DC in one direction. Hence its use in DC polarity protection applications.

Nige

[Duotone]

Originally Posted by Ennine

Surely a diode (rectifier) will pass DC happily. In fact its characteristic will allow it to only pass DC in one direction. Hence its use in DC polarity protection applications.

Nige

Quite so.

I was referring to Klarzy's post.

"replaced sidelights on my ztt with quad ring led DRL's, each of these has what I can only assume to be a rectifier (4 in total) as the led rings will light whatever the input polarity."

This is the meaning of rectifier.

A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.



By rectifier I think the op means diode.

I don't know the reason you would fit diode's to drls. If you have diode's in the circuit then the led lights would light if you connected the wires one way round but not light the other way.

Dave T

[Ennine]

If a bridge circuit was used then the leds would light whatever polarity was applied. Obviously taking into account any voltage drop that no doubt would be factored in at design level.
Thanks for the definition of rectifier.

Nige

[klarzy]

Originally Posted by Duotone

Quite so.

I was referring to Klarzy's post.

"replaced sidelights on my ztt with quad ring led DRL's, each of these has what I can only assume to be a rectifier (4 in total) as the led rings will light whatever the input polarity."

This is the meaning of rectifier.

A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.



By rectifier I think the op means diode.

I don't know the reason you would fit diode's to drls. If you have diode's in the circuit then the led lights would light if you connected the wires one way round but not light the other way.

Dave T

I was aware that a bridge rectifier contains 4 diodes mounted in opposition and feeding mono polar current from an AC source by acting as a gate and normally balanced for the AC waveform by a capacitor.

the device as sold in the ebay add states a current stabiliser so as this is a Chinese product I read this as a voltage regulator, as the device will work in either polarity and produced a stable light at 9 or 12 volts I am assuming a rectifier / capacitor arrangement. The question is would 2 in parallel cause interference feedback on a 12v system fed by an alternator... especially one which I suspect has a less then 100% healthy charge controller....

deep breath...

[Ennine]

It is quite possible that these units are causing noise on the feed (as you suspect). Does the navall take a illumination dim feed when the sidelights are on? Dropping the dim feed to the Nav' or hooking up a temp' feed to the lights direct form the battery (for example) may help to prove the point one way or the other.

Nige

[klarzy]

Originally Posted by Ennine

It is quite possible that these units are causing noise on the feed (as you suspect). Does the navall take a illumination dim feed when the sidelights are on? Dropping the dim feed to the Nav' or hooking up a temp' feed to the lights direct form the battery (for example) may help to prove the point one way or the other.

Nige

no, the facility is there but not used, the effect is only on the radio app also so I suspect as said before that there could be signal noise from the rear light wiring where it runs parallel to the aerial although this should be shielded coax... and the rear feed is separate after the LSM...

I have a similar issue on the other car but this causes interference when the hd cameras power up from a switched feed in the passenger fuse board...

[Ennine]

If that's the case then it sounds very dirty (you know what I mean) indeed. As you suggest the cable must be screened. As you know, at RF frequencies that type of noise can creep in almost anywhere hence my question about the illumination feed, Is it remotely possible it is actually being picked up by the antenna itself ?
Nige
Just a thought. Do you own a 'scope ?

[klarzy]

Originally Posted by Ennine

If that's the case then it sounds very dirty (you know what I mean) indeed. As you suggest the cable must be screened. As you know, at RF frequencies that type of noise can creep in almost anywhere hence my question about the illumination feed, Is it remotely possible it is actually being picked up by the antenna itself ?
Nige
Just a thought. Do you own a 'scope ?

sadly no, had a fluke scopemeter but sold it when times were hard....

the coax route only encounters the lighting loom over the rear wheel arch, that is where I will look, but the issue was not there prior to the drl install so noise must be coming back through the LSM ??

[Ennine]

Having just done a very quick search it would seem that many of these DRL's Quote: "Many of the “online” products have proven to be unreliable and more concerning radiate vast amounts of RF noise effecting FM and DAB radio reception."
It would seem between 30 - 300 meg range. Looks like you may need some filtering!! I suppose you may be able to confirm it by running a hand held fm radio over the car. Obviously there would be no cable induced sympathy but if you pick it up on a stand alone radio you will know you are dealing with a fairly serious issue.
Sorry I can't be of any more help than that. I'm interested in anything Navall at the moment as I currently running cables for mine and trying to make it as future proof as possible.

Nige