Low Pass Filters (for cb).?

Hi ‍� 
I wasn’t sure exactly where this should go so if there’s a better page please feel free to move it on. Thanks. 

I’ve been reading and watching YT about low pass filters and wondered if people are still using them to reduce harmonics interference on other bands or electronic equipment nearby?

If so which make are you using?

Many thanks 

John

I can only answer for myself and my mates and the answer is no not really, i myself have never used any filters at all and never had any problems, but I can't answer for others.

I actually run one on each antenna... just because.

I.C.E 421 HF Low Pass filters.

I had them from my previous QTH, so I put them back up

I use to run low pass, or band pass,  filters on all of my radios at one time. I lived close to the perimeter fence of a airfield & it saved me from being accused of anything. 

I also ran band pass on my ADS receiver, before they stopped taking input from windows. It made my RX work a lot better.

I’m not, so sorry can’t help on makes. Am not running any additional power at home either, only what the transceiver itself can put out, and although insertion loss is probably negligible it would irk me knowing I would be losing anything of my limited power by putting one inline. I would of course though if a neighbour said to me they were having problems.

I have ferrited the power cables though as that helps stop interference incoming and outgoing over the mains.

Do CBs still cause interference to TVs and other things much now though? Seems to be more the other way round since I’ve come back to this.

From watching the videos etc they are used to prevent harmonics dropping up and down onto other bands. 
I’m told the filter can also prevent being picked up on speakers ( not like the old days where you hear every word) but it may stop clicks of the ptt switch. 
Also I’m told cb can still cause problems with wifi modems too. 

I use legal power too. 
So I don’t interfere with others as far as I know but would like to take all precautions that are reasonable. 

Thanks for people’s responses and any information on where these filters have been used in personal experience would be very helpful.

SangueG wrote:

Do CBs still cause interference to TVs and other things much now though? Seems to be more the other way round since I’ve come back to this.

Anything & everything is now, more than ever, likely to cause QRM to a TV, due to their build quality now. HOWEVER. All that normally happens now is that  the TV's screen goes blue. Where it used to be audio breakthrough, lines etc etc. With digital TV, it is far far more likely to be the screen going blue & to make things even better for us, TV repair people & so called antenna specialists, now know less than they used to. So the chances of anyone finding out what is happening is not really a problem for us now, as much as it used to be. 

A friend who runs a TV repair & TV antenna business, was telling me that an  analyser to see what is causing problems to a digital TV's signal, costs around £2000+. How many businesses are going to pay that?

I’m looking at this for me as much as anyone else.
I don’t want to spoil anyone else’s pleasure of listening to music or watching tv because of my hobby if it can be prevented.
I see it as a duty of care when I use my radio. ‍�

Tristar wrote:

I don’t want to spoil anyone else’s pleasure of listening to music or watching tv because of my hobby if it can be prevented.

The problem is that now, most technology is built to the lowest & cheapest possible standards.  

Filters will protect others to a certain extent. Which is why when I lived close to the airfield, I used filters. It was the considerate thing to do.  But filters will only help those using well made equipment & that means not much if any domestic electronics & only some commercial equipment. Your best protection against your equipment being the cause of interference is a wave absorption meter. Check for unwanted RF on unwanted frequencies. 

I do not know about now, but when the GPO/DTI visited a radio amateur. An absorption wave meter, was one of the first things they asked to see. 

Back in the early 80's I think it was. A new legal FM station in London received a complaint from either Gatwick or  Heathrow complaining about interference to aircraft landing there. The resulting investigation was widely reported in the amateur/swl community. As it said that the broadcast transmitter was clean & well filtered, but that multi million pound aircraft,  which had radios that needed to work properly, were fitted with poorly designed radios not capable of working safely in the real world. Another incident around the same time found that GCHQ, who had  made a complaint against another broadcast station. Had not maintained it's equipment for years. So GCHQ was shouting national security is at risk, but a spark, with a paint brush solved the so called interference problem by simply  dusting the inside of the radio receivers.

TBH I've also experience from some the low /high pass  filters can actually cause interference when put in line more than if they was not ,TBH if you don't get any complaints I wouldn't bother unless someone says anything or you 100% know your giving interference, actually the modern electrical stuff that's about ie: LED lights, WiFi routers , certain flat screen T.Vs any many ore things cause more interference to CB and Amateur radio than the radio does to modern electronic stuff.

Well I decided to put one in line. It hasn’t effected the swr and power lose is minimal.
It’s in line and I don’t even know it’s there so why not.
Many thanks for your answers and thoughts.
Much appreciated!

Fortunately enough, it is not something I have had an issue with this time around, the positioning of my antenna is away from the house and more importantly the houses of others and in the advent of the digital age, many peoples televisions are no longer used as receivers but as monitors for cable boxes, satellite receivers smart TV devices etc. 
 
The electronics have improved too, changed would probably be a better term, there doesn't seem to be so many items that can be directly affected in daily use around us, if you think back we had cordless phones, baby monitors, remote control devices and a whole host of items using 27MHZ alongside the C.B. bands and you just dont see as many of them in daily use around us any more.

It is the endless wireless technology and LED lighting which appears to cause interference with our radios I find has been my own experience, I was able to remedy this in part, at least, using ferrite rings on the power leads of the worst offending items.
I opted for mix 31 and 43 at first having had little success but then I noticed in the first licence manual I hadn't wound it correctly, after correcting the way it was wound it reduced my nose floor by 3-5 S points across the HF bands including 11m of course and it really cleared things up on 144MHZ and the PMR frequencies allowing me to hear a friend on his handy in a nearby village where I couldn't make him out clearly at all for the QRM that came in with his signal.

Being a great believer in "If it ain't broke dont fix it" I will leave well alone but should I have any issues in the future I most certainly know where to look and I am sure this will prove invaluable information for those on a quest to eliminate interference from our stations.

73's

Alan

Hi
Just a quick update.
I’ve put a kenwood low pass filter in line as I said above and had it constantly inline.
The people I talk to on a regular basis have not noticed a difference in my signal they receive so if it prevents unwanted harmonics dropping onto other bands and keeps my signal clean then I’m happy.
Thanks for all the comments guys.
Catch you on the flip flop!

Hello
Why does it say I’ve been banned from the forum?
And for what?

????????

Tristar wrote:

Hello
Why does it say I’ve been banned from the forum?
And for what?

????????

How can you be banned if you can still post.

It doesn't say you are banned from the forum John or as Alan mentions you wouldn't be able to post to the forum at all.

Someone else was banned but you can still see their responses by clicking the "See the message" link next to the 'The author of this message was banned from the forum'.

Forum bans are thankfully a rare exception and usually come about after considerable/multiple warnings as well as first working with the member involved. Except in extreme circumstances bans are usually a last resort decided by the whole admin team members and usually when accompanied by other members complaints.

Bans shouldn't really happen, it's not that hard to be nice to each other.


Hope that helps.

All the best,
Victor

(CT Admin)

Can't see where it say's anybody is banned lol.

To be honest Alan, blink and you'd miss it - we don't like to make a big fuss of such things.

(Small grey line between a couple of the postings.)

Many thanks guys.
I was worried I’d done some wrong that I wasn’t aware of !
I often miss seeing things but I thought I would have noticed

I love coming to the forum and checking out what’s happening so although I don’t post as often as I probably should I do like and add comments where I think I’ve something to offer.

All the best.
John.

No worries at all there John and glad that's settled your mind.

All input to the forum and other members is always appreciated no matter how big or small and especially when given in the spirit of helping each other enjoy our passion & pursuit of radio.

I've bunged you a 'Thanks' for your continued contribution.


All the best,
Victor

Spotted it Victor thanks.
John
You might get a slapped wrist first before getting banned (had it myself  lol)..

Haha
Many thanks!