Importance of Low Pass Filtering in the hobby.

www.scottsradios.com

[@DeltaXray444]

great advise for any rig user and a very good demonstration showing the difference before and after.. big thumbs up.

[@ScottsRadios]

Had a chance to work some European DX yesterday, that was fun.

[@DeltaXray444]

@@ScottsRadios yes the states have been jumping the pond for a few weeks now and getting stronger.. i had new york south cara tampa bay and michigan yesterday.. it raised an eyebrow with the tampa contact especially with the storm blowing in.

[@lostsoul3535]

Thanks for the information. I appreciate the comprehensiveness of the video.

[@TheArtofEngineering]

Awesome education. This is why CB was an apparatus license. Each unit was tested to meet FCC requirements for spurious emissions (harmonics, intermods and spurs). This is why I’m order to “play” radio we need as a community to understand this stuff, lest we ruin the fun for others on the radio spectrum that we all share. So play safe use the LP filter. 73

[@GroundControl204]

One of the best videos you got brother. Informative and directly to the point. 73

[@ScottsRadios]

Thanks, keep up the good work.

[@miker8379]

Great video. RM Italy are known for spurious emission

[@electromechanicalstuff2602]

I'm running a 955 and I turned the modulation down to 80% at wide open mic. I turned the dead key down to about 1/4 watt. I drive that into a 2x8 Fatboy. 200w dead and 1200 pep I have a 3kw low pass and I use a nano vna and it's clean clean clean. I've had people drive near me and my neighbor who uses an icom 7300 and only heard him while he was barefoot on the adjacent channels only slightly. I strive to stay clean. I wish more people did too. I talk to a few people from 10-40 Miles on a regular basis with a IMAX 2000. I need to get a sampler slug so i can get a direct sample

[@glaucovasconcelos5302]

Muito grato pelo vídeo! Este tipo de amplificador linear é uma grande ilusão!

[@ScottsRadios]

Gracias por ver. Estoy de acuerdo con usted. Uso el traductor de Google para responder. Mejor 73!

[@JustAnumbr]

Mike I’m curious to know if the filters block incoming emissions and would be worthwhile to install in a modern semi. These trucks have lots of RFI from many sources as well as inverters. I’ve ordered some ferrite’s for when I install too.

[@ScottsRadios]

It does block some incoming. Noticed if I have a radio that's NOAA capable it will block out the reception pretty much. That's not saying that it's going to block out unwanted interference though.

[@flhusa1]

I run my RM ITALY Amp the same way he hooked up the filter. Double male right off back of radio. One less jumper and reduced loss

[@ScottsRadios]

Easy way to do it.

[@flhusa1]

@@ScottsRadios takes a litte more room to mount it somewhere. But where there's a will there's a way .

[@turboomni848]

I am running the same Low Pass Filter on my base station with a RM503. I use an amp only because my location is not a good one to get out easily. I use the Low Pass to make sure neighbors have nothing to complain about. My reason for posting here is RM Italy makes small Low Pass Filters and was wondering if you could test one out or recommend a small one for mobile use? Good video as always.

[@ScottsRadios]

I think I did a video a long time ago showing the Rm Italy low pass filter. Although it does work from my memory I find that the one in this video works much better.

[@ZommBleed]

@@ScottsRadios What would be your opinion on running the same low pass filter on the input as well as the output? Would filtering what goes into the amp do anything significant prior to amplification or would that just be a waste of money?

[@ScottsRadios]

@@ZommBleed that would depend on what type of radio is being used. If the radio has an onboard amp then yes absolutely. Main thing to consider is these amplifiers are not linear in any way. They should be called Power producers, because that's all they do. Spreading power out over multiple frequencies instead of homing in on the one desired.

[@flhusa1]

RM ITALY has a amplifier with selectable filters built in. You will have to look up the model.

[@ScottsRadios]

Yes, they do have actual approved amplifiers but they are very costly and only for amateur radio.

[@rudykay5618]

Does it make a difference which way you hook up the filter it say 50 ohm on both ends

[@ScottsRadios]

Generally no. Some filters well specifically say, some will not.

[@Cr8MyLuck]

Hello, As long as you don't use a amplifier you should think about sending me one.😊 I need one for the PA on the CB. I don't use the CB unless it's for some crazy emergency. Nice equipment though. Wish they had a sign wave amp for CB Would get a cleaner signal.

[@ScottsRadios]

There are many amateur options that can't be used but multiple avoid them due to high cost.

[@414730]

Now were those harmonics being generated by the amp or the radio?... it would be interesting to see if you put the filter on the output of the radio or the input of the amp

[@ScottsRadios]

It's definitely the amp. I can easily do a video if I had time to show that the radio is definitely not producing harmonics like that.

[@ScottsRadios]

I have no reason to lie or make stuff up. I don't do this for a living. I do it because I enjoy the hobby and I like to put the profits that I make directly into my business. Whether it means buying test equipment, more products to try and sell, or maybe even something nice for the wife 😆.

[@414730]

@@ScottsRadios I was not implying you were not telling the truth, just that some radios stock are dirty with harmonics from the get go and was wondering if the 980 was also

[@ScottsRadios]

@@414730 Not unless it's highly modified. Maybe even not as bad then. I do agree with you, many radios are horrible and with pointless modification's even worse.

[@dougmorris4487]

I run one on the output of my radio and on the output of my amp. Works very well.

[@ironhead320]

Is there a way to test this filter I got one just like it and on my 69ffb4 it shoots the swr's up over 3 but my antenna set at 1.3 with a analyzer.

[@ScottsRadios]

Connect to 50 ohm dummy load to the output side of it and you're analyzer to the input side.

[@ironhead320]

@@ScottsRadios ok but this doesn't have writing on it saying input or out put or don't it matter

[@ironhead320]

​@@ScottsRadiosdid just that and my swr's on the analyzer shot up to a 6

[@ScottsRadios]

I think your filter is defective. Possibly, someone ran way too much power through it.

[@ironhead320]

@@ScottsRadios ok kind of thought it was bad

[@bblod4896]

Depends on who builds the amplifier. The mass produced will amplify harmonics. Cleaner the input signal, the better the output. You know the saying: "Garbage in... garbage out". Meanwhile, I'm watching my antennas sway but the hurricane is 200 miles West if me heading North.

[@ScottsRadios]

Stay safe.

[@ScottsRadios]

Yeah I get what you're saying but I've showed it times before that these RM Italy amps also create their own issues by themselves. You don't even have to have the amps power switch on and it will create unwanted out of band spurious emissions, simply by transmitting your radio through it.

[@bblod4896]

@@ScottsRadios Yep. Real amateur radios don't have the same issue due to their band switching. Notice, the non-FCC amplifier works from Khz to Mhz, no filtering

[@mrjones6770]

Even ham radios do this as well...but it's so low people in the area won't notice it...but you will if you hunt the frequency at home ...cb amps are aggressive at it is all...ham rigs not so much, but still do

[@ScottsRadios]

Best to filter all of it.

[@justinmaas5834]

I noticed quite a rise in SWR using the exact same Drake filter on a 203/Bearcat combo.

[@ScottsRadios]

I shouldn't raise your SWR. Probably need to change your jumper length to something more suited for your installation.

[@justinmaas5834]

I revisited this setup and experimented with a variety of setups with mixed results. I suspect that the rather aged filter may be part of the problem. Keep up the good work, I think your philosophy of use and approach to tuning is a welcome option in a world of dudes yelling AAAAUDIO.@@ScottsRadios

[@ironhead320]

Where can I get one of those filters

[@ScottsRadios]

Check on eBay there are lots being sold.

[@ironhead320]

​@@ScottsRadiosgot one 15.00

[@N64player1996]

​@@ScottsRadios I'm looking at adding one of these behind a Texas Star 500/667. My SWR while it's in line but turned off is 1.1 across 40 channels. When the DX500 is turned on is 1.5 I'm debating picking one of these up to see if it would help with the mismatch slightly occuring. As well as cleaning up the signal. Would it also benefit more to try to source a 50ohm filter or does it not matter between the 50ohm and 52ohm? Best regards, thank you for the informative video.

[@bblod4896]

Also, for legal reasons, better off not getting involved with amplifiers

[@ScottsRadios]

Yeah I'm not going to promote something that I won't use myself. Maybe I'm just getting older but I don't care about power anymore. With the right conditions power is a non factor.

[@dharmadove]

As a ham, I worked over 48+ countries on my Uniden 2510 mostly on a hamstick on my truck. In rush hour. Peak of the late 80's Sunspot Cycle.. Even East Germany who doesn't exist anymore. My best was a mag mount with the same radio on an A/C unit in the 7th Floor of the then Holiday Inn one early AM. In Laredo, TX I had a QSL with a Japanese Station on 10 Watts. Never needed a linear for 10 Meters. Now 6 meters it helps depending on the propagation mode, a decent antenna always more. The President and CEO of one of former employers worked 6 meter moonbounce. He could afford multiple 60+ foot yagis. Pointed a big phased array towards the moon coming up or going down. Traveled around the world doing it. Antennas make big difference. Best thing too is a good tune up and alignment of your rig too. By a vetted pro like the poster of this video or if a ham with / properly licensed with professional equipment, It will last!

[@flhusa1]

Can't beat PRESIDENT HR2510 . I own the only 3 HR2510's with Moffett finals in existence.

[@scottb5662]

The spectrum is a mess. Good for us all to run as clean as possible.

[@stargazer7644]

All of it is completely illegal.

[@ScottsRadios]

Read my disclaimer. I have them posted on my page and also on lots of my videos.

[@Alien_O1]

You dont run amps. You also dont run amps. You dont like running amps. And finally you dont like amps.