BCT-15 Power Question for Mobile Install

[SCPD]

(Mainly a question for Upman)

Is there any internal difference about whether I'm using the 3-pin DC power or the standard DC power jack? Is the 3-pin DC power filtered for mobile use?

Currently, I'm using the standard DC jack (not the 3-pin) for my mobile power install. It's working fine but I'm hearing what I think might be some noise. (It sounds like fast, low-pitched bubbles.)

My power is positive to fuse-block and negative to chassis ground; but, I don't think my power connection is the problem, as my Icom V-8000 doesn't have this "noise" sound.

I'm monitoring strictly 860-869 Mhz on the BCT-15 so I'm curious if this is a normal issue with monitoring mobile trunks. I seem only hear this 'noise' when someone is transmitting thru the trunk. It's not continuous though - it happens randomly at various times. I can be idle, sitting in traffic and the audio sounds crystal-clear.


-Nick

 

[UPMan]

There is no difference between the two power inputs.

I also hear some background data noise occasionally on the analog trunks I monitor. It is usually pretty low (I have to listen for it) and I hear it regardless of being mobile or fixed-base.

You could try sitting in the car with the engine off and listening for a while to see if it is there when the car isn't running (which would rule out a power issue).

 

[SCPD]

Thanks Upman - that's good to know.

Hmm - interesting point about the background data. That might be it - since I seem to only hear is when someone is coming thru the trunk.

I have a perm NMO mount on the roof of my vehicle - attached is a Larsen 800NMO (18") and I'm wondering if that might be "too much" antenna for this scanner.

A friend suggested I try an Antenex Phantom. (A low-profile 3" antenna) instead of the whip.

 

[scanbc780]

I can hear something as your describing on almost all analog voice on Motorola trunking. I am assuming its the data that is transmitted at the same time as a transmission. If I am using headphones its even more pronounced.

 

[SCPD]

Hmm.. I guess that's somewhat re-assuring. I do not hear this on my BC396T - never have - even with headphones. Perhaps it's an issue with the BCT15 then...

If you call power off on the volume control at 6pm... I crank my volume to about 2-3pm while I'm in the vehicle. When this noise does happen, it is very pronounced. It's not enough to displace the audio from being understood - but it is annoying.

I'll hook up my BC396T to my vehicle antenna and see if I can reproduce this...