• To anyone looking to acquire commercial radio programming software:

    Please do not make requests for copies of radio programming software which is sold (or was sold) by the manufacturer for any monetary value. All requests will be deleted and a forum infraction issued. Making a request such as this is attempting to engage in software piracy and this forum cannot be involved or associated with this activity. The same goes for any private transaction via Private Message. Even if you attempt to engage in this activity in PM's we will still enforce the forum rules. Your PM's are not private and the administration has the right to read them if there's a hint to criminal activity.

    If you are having trouble legally obtaining software please state so. We do not want any hurt feelings when your vague post is mistaken for a free request. It is YOUR responsibility to properly word your request.

    To obtain Motorola software see the Sticky in the Motorola forum.

    The various other vendors often permit their dealers to sell the software online (i.e., Kenwood). Please use Google or some other search engine to find a dealer that sells the software. Typically each series or individual radio requires its own software package. Often the Kenwood software is less than $100 so don't be a cheapskate; just purchase it.

    For M/A Com/Harris/GE, etc: there are two software packages that program all current and past radios. One package is for conventional programming and the other for trunked programming. The trunked package is in upwards of $2,500. The conventional package is more reasonable though is still several hundred dollars. The benefit is you do not need multiple versions for each radio (unlike Motorola).

    This is a large and very visible forum. We cannot jeopardize the ability to provide the RadioReference services by allowing this activity to occur. Please respect this.
  • Effective immediately we will be deleting, without notice, any negative threads or posts that deal with the use of encryption and streaming of scanner audio.

    We've noticed a huge increase in rants and negative posts that revolve around agencies going to encryption due to the broadcasting of scanner audio on the internet. It's now worn out and continues to be the same recycled rants. These rants hijack the threads and derail the conversation. They no longer have a place anywhere on this forum other than in the designated threads in the Rants forum in the Tavern.

    If you violate these guidelines your post will be deleted without notice and an infraction will be issued. We are not against discussion of this issue. You just need to do it in the right place. For example:
    https://forums.radioreference.com/rants/224104-official-thread-live-audio-feeds-scanners-wait-encryption.html

RFI Chokes..

Status
Not open for further replies.

DK327

Member
Premium Subscriber
Joined
Sep 15, 2014
Messages
26
Location
Omaha, NE
#1
I have an issue with my mobile cb setup where while I'm driving around in town, I'm getting a lot of interference on intersections where there are traffic lights. Soon as I pass them, the noise goes back down to "normal" level.

I took a couple of long trips recently and all channels were very quiet while I was driving thru the countryside so the RFI is definitely caused by power lines, traffic lights, etc and not the alternator or the electronics in the vehicle.

I read up on how to reduce this type of RFI and found out I might need to get a Mix #31 ferrite (2.4" round) and 7 turns for best reduction...but have a couple of questions:

Where do I place this ferrite on coax? Near the radio or antenna? Do I need more than one? Does it degrade the transmitted signal any? Is it possible that the signal is actually being picked up from power line going to the battery, acting as an antenna, instead of the RF line to the radio? If so, can I use the same ferrite on the power line to the battery? Would a MFJ 915 do the same thing? It's supposed to be 1:1 but I think it would eat up some power?

Any help is much appreciated.
 
Joined
Dec 13, 2007
Messages
663
Location
Mojave Ca
#2
Hello DK237: This doesn't sound like a RFI issue that can be fixed by installing ferrite cores or bypass capacitors in your vehicle. Due to the RFI having the same frequency as the CB stations.

If the radio and antenna are installed and working properly theres not a lot you can do, you have to take the RFI and the city at the same time. Maybe turn on the NB (Noise Blanker) or turn down the RF Gain, or turn up the Squelch. Or use a DSP Speaker, I run one of these and its a big help:

West Mountain Radio - CLRspkr ClearSpeech® DSP Noise Reduction Speaker

RFI needs a Generator - Path - Receiver if any of these can be eliminated your noise free. However the noise is on the CB Band, and I don't think the local authorities would appreciate you climbing up on the signals posts and installing ferrite cores. (hopefully humor)

As I drive the big city of Los Angles at times I can hear all kinds of noise. Some noises even interfering with the local 2 meter repeaters being received. And that's bad. There is one intersection that has to be a major RFI source / generator as I hear all kinds of noises, beeps, hash, blow torch, and frying bacon all at the same time, on different bands how wonderful. However the DSP speaker does reduce much of it.

The MFJ 915 I believe is for transmitting issues keeping RF off the coax shield. You can try different things such as ferrite cores say at the antenna end, and or the radio end, with the coax wrapped around the ferrite core, but may not make any money doing so. In some cases you just have to live with the noise until we have digital receivers that are programed to eliminate or reduce the noise in receivers. Good luck, let us know what you come up with.

Jay in the Great Mojave Desert... yeah yeah it gets hot here, 103 is predicted that means it will be 110 here today
 

DK327

Member
Premium Subscriber
Joined
Sep 15, 2014
Messages
26
Location
Omaha, NE
#3
Jay in the Great Mojave Desert... yeah yeah it gets hot here, 103 is predicted that means it will be 110 here today
I bet "patrolling the Mojave almost makes you wish for a nuclear winter" ;) Stay cool and thanks for your response! The product you mentioned sounds good although I'm not too impressed with the price. I think I'll experiment with coax wrapped/clamped around ferrite on both ends and see if it helps any, like you said I just might have to live with it...
 
Status
Not open for further replies.
Top