Would you like to react to this message? Create an account in a few clicks or log in to continue.
Welcome to the Charlie Tango DX Group. The home of ALL things Radio - CB, 11m DX, Amateur, PMR446, PLD, Network and Data. We welcome all radio enthusiasts of all knowledge levels. Join today and claim your own unique World Famous CT Call-sign
Have You Just Arrived From Old Forum? : If you have then you need to click "Join CT" and register an account on this new forum. Your CT call sign is still valid and you don't need to apply for a new one.
CT Summer Prize Draw: Win a Brand New President Mckinley 11m all mode radio!! See the Latest News forum for details.
Still Time: There is still time to buy a ticket for the raffle. See news forum for details.
Latest News: If you are trying to log in to this forum using the login details from the old forum they will not work. You must register a new account here to be able to post. Your CT call sign is still valid, you don't need another one.
Latest Buxton 2020 News: Unfortunately, due to the Covid-19 pandemic we have had to cancel this year's Buxton date. Sorry for any inconvenience.
Latest News: The CT website is now fully secure with an SSL certificate so you never have to worry about security or privacy when online at Charlie Tango.
Thanks for your patience: We are glad you all approve of the changes and to the forum and for all the great feedback received. There are just a couple of creases to be ironed out now which are been currently worked on.
Call Sign : 26CT3112 Posts : 5 Times Thanked : 0 Join date : 2020-01-02 QTH or Location : ilkley west yorkshire Equipment Used : 6900n/major 3000fm/ silver rod ant
Subject: xphase qrm eliminator Sun Jan 12, 2020 10:36 am
has anybody used an xphase qrm eliminator? does you aux antenna have to be near your main antenna? i,ve really bad qrm on my radio all day, buzzing and pulsing making radio use almost impossible. any help or advice most welcome..
Call Sign : 26-CT-3228 Posts : 266 Times Thanked : 25 Join date : 2019-11-10 QTH or Location : Bedford Equipment Used : Various
Subject: Re: xphase qrm eliminator Sun Jan 12, 2020 11:56 am
The x-phase and other QRM killers do work to various degrees, (when set up properly, they're flipping marvelous!)
Your main problem is that they usually have a PTT, (push to talk), control circuit to switch over the TX/RX bypass. Not a problem with Ham gear as they have such control outputs but CB's usually don't. If you transmit into such a unit without it you're likely to make it blow.
That being said I have seen people hook up a manual switching arrangement but that's going to become rather tedious. I've also seen people modify them to 'auto-switch' on TX much like a preamp does, not the best solution as you'd better be putting low power in it.
With that, the best advice I can give you is to make sure your own property isn't the source of your QRM woes
I hooked up my rig to a 12 volt battery, turned off the house mains and a lot of my QRM disappeared! Took some hunting but landed up throwing away two cheap phone chargers and much to the annoyance of my XYL one of those "plug-in smellies" Some clamp on ferrites were also used on my Samsung TV and the home PC reducing the noise even further.
I still have some noise problems, more than likely neighbours equipment but I can't be bothered with the politics and dancing involved with 'neighbourly love' disputes. Heck, all my antennas are loft hidden affairs and no one knows I have radios......that way I don't instantly get blamed for TV/satellite/internet/phone or other such nonsense interference complaints (???!)
There's a ton of information and YouTube videos about tracking down QRM, all helpful stuff.
You could also do what many others have discovered......put the rig in the car and drive away from 'civilisation'. Not much QRM atop a lonely, quiet, rural hillside
A bit of separation is helpful for a couple of reasons - first so that you don't cook your phasing unit with the RF coming out of your main antenna (I know the MFJ boxes use a lamp internally as a "fuse" against this happening, but it's not foolproof - I picked up a "dead" one with the bulb blown and a transistor shorted) and secondly so that there is some clear phase difference between your "wanted" signal and the QRM reaching the box.
The problem is that for a lot of us with "urban" QRM - LED lights, solar panel inverters, leaky broadband etc - there are multiple sources coming from different directions and you can't guarantee a box can take all of them out (because they arrive with different phasing in each case). But the Xphase gets decent reviews and if you can find a source pre-built (there are lots of kits) they seem a lot cheaper than the MFJs.
the qrm source is definetly not from my house. more tha likley solar panels across the street. got an xphase from e-bay in post whtch has auto rf switch so dosent need ptt switch. i hope it solves the problem.
Hi, The x-phase reduction units do work when set up correctly and are particularly useful when they have the auto rf switch and used on the standard CB radio's etc and are used on the FM and AM bands. How would you use them for SSB radio's like the SS 6900's and SS 9900's etc that dont have a PTT connector and can't use the auto rf switch. Thanks.