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Reviews For: QRM Eliminator X-Phase by RA0SMS

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Review Summary For : QRM Eliminator X-Phase by RA0SMS
Reviews: 7MSRP: 75
Description:
Noise eliminator
Product is in production
More Info: http://www.ra0sms.ru/p/qrm-eliminator-x-phase.html
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0075
KE7OPK Rating: 2022-08-20
BIG Improvement Time Owned: 0 to 3 months.
Very easy to adjust - very coarse adjustments - extremely effective without needing much skill to operate - better results than DNR could ever hope for. Delivers a nice, quiet band and removes some very strong signal (which is modulated, starts out below the BCB and has spurious emissions and harmonics littering ther entire spectrum, even drowning WWV) and has given me immediate results - night and day - all sorts of noise is GONE. Does not degrade the signal you want. Maybe a Timewave is worth the extra $$, but this will let you know if a phase cancelling noise reducer will help in your unique environment. Main antenna is a "Marconi" monopole. I am using a 10 Meter BNC antenna with a long telescopic element I got on ebay, which is specifically designed for 28 Mhz, but is is doing the job all the way down to 10 Mhz (WWV), and may just be a good choice for the sense antenna. Super value, unexpected results, decent build, super bargain worth every penny! I own the "PLZ QRM - X ..." with a rocker switch on the front (not all are built the same).
GW4DVB Rating: 2020-11-24
Does what it says on the tin ! Time Owned: 6 to 12 months.
Many Radio Amateurs, new and old, suffer from man-made interference that renders the HF bands useless. In the past I too had problems and have tried many cures including specialist antennas and filters.

By way of a project to help with my local noise problem I spent months trying out branded products until I found SOMETHING THAT WORKED !!

"The X-Phase QRM Eliminator" actually worked for me and is just a fraction of the price of the commercially sold Noise Eliminators sold through MFJ, Wimo etc. - I've tried them all !!!

If you Google ‘QRM Eliminator X-Phase’ and read up on them here on eham.com you will see what it is and how it works – There are some good videos too ????

For the practically minded they are available it PCB kit form via eBay and AliExpress.

I am so thrilled with it's performance that during my spare time I have been making small batches which are fully assembled in a die-cast box with all connectors etc which I have decided to sell on to our local radio club members..

Cheap but highly effective !!!
K2TL Rating: 2020-11-10
Amazing performance! Time Owned: 3 to 6 months.
I bought the full package with the RF sensed PTT and a nice enclosure. Cost about $100 shipped to NJ. There are kits, fully assembled boards, and optional enclosures from many different vendors, but I decided to go the lazy way. You can shop around and find the one you like best. eBay has a bunch. I use the PTT and 13.5v lines from my FT-950 to control and power this device. As far as performance, it is almost hard to believe! I can take a S9 plus 20 db noise and reduce it to just about nothing. It takes a bit of practice but once you get it figured out it is a breeze. I had once owned an MFJ noise cancelling product and never could get it to work. My noise antenna is a homebrew active loop. This is not a DSP or noise blanker. It actually removes the noise before it reaches your receiver.
AI7R Rating: 2020-11-08
Oh my this is amazing!! Time Owned: 0 to 3 months.
I found this to work amazingly well. If you want to get that pesky noise floor down, especially if you live in the subs and have a gazillion devices screaming on HF. My noise level is typically S7 to S9 on a CCD dipole 20 feet over the roof. My sample antenna is a 17' dual band VHF/UHF antenna on the roof. The CCD is typically a quiet antenna that's close to loop levels. So, with a normal dipole I'd have a LOT more noise. I made a video for those interested. You have to see this to believe it.

BTW, this is a kit. There are dozens of vendors with kits as well as some assembled ones.

KD7RDZI2 Rating: 2020-07-08
Every each ham should have it! Time Owned: more than 12 months.
First the KIT arrived from Russia well within the expected delivery time. The KIT comes with a very nice board, some SMT components and few discrete components, 3 quality potentiometers and knobs! If you plan to mount the KIT, I have to say the SMTs are really small. It is not difficult in general to mount SMTs but these are very small and I had to pay more attention than hoped to mount them. There are cheaper chinese copies of the board on ebay. I can only comment on the kit I assembled sent by RA0SMS.
The kit worked immediately. The schematic is similar to the MFJ-1026 I have but are not the same. The MFJ does have RF-Sensing but does not have a relay for the AUX antenna. This unit has a relay for the AUX antenna but no RF-sensing. I have seen assembled units from Ukraine having the RF-sensing and other changes to this design. The MFJ and the Ukrainian unit has in addition Time Delay. Here is just a PTT. All these units use the same JFETs, J310. The MFJ uses 3 J310, while this unit just 2. Being used to the MFJ unit, I initially thought it was easier and more logical to use. The AUX Gain Control and Phase Control seem to act similarly in this unit. However I have to say this unit works works very well indeed. IMHO I find ridiculous to buy expensive transceivers with DNR and other amenities that do not have such a simple circuit and three additional knobs!
A modern transceiver should have two antenna inputs, bandpass filters and then this kind of circuit, that is well known since ages! DSP, DNR, notch filters can do nothing compared to this simple solution. These circuits, included the MFJ 1025-1026 do not have bandpass filters before the J310. The J310 are good devices and looking at the datasheet they have a quite dynamic range. Of course adding bandpass filters would be technically the optimal solution (I have some of them, some completely homebrew) that would exclude almost any saturation possibility. In any case, the gain of the unit is very low if any and is quite robust to large signals. In few words, the bandpass filters might never even be really needed to avoid saturation within this unit. Is this a "nice to have"? Maybe not as nice as the newest transceivers, surely it is "useful to have".
VK4WTN Rating: 2019-04-08
a nice surprise Time Owned: 0 to 3 months.
I purchased this unit from ebay and it arrived in very quick time.I am still experimenting but the trick with this unit is getting the noise antenna to pickup a similar amount of noise as the main antenna. I have a constant s9 noise floor on 160M and for some reason on 30M.I initually couldnt get the noise antenna to pick up enough noise but I used my cobweb antenna as a 160M rx only antenna (about s5 noise on this antenna and I was able to phase the noise level to s1. Ran my rx overnight on 160M and copied many US and EU stations on my now noise reduced cobweb rx antenna. I now plan to build either an FO0AAA rx antenna or K9AY antenna and permanently used the QRM eliminator on that.I have bought several other items from RA0SMS and he never disappoints.
G0CGL Rating: 2017-08-23
Inexpensive and does the job Time Owned: 3 to 6 months.
There are several competing products for antenna line noise cancellation devices. They all work on the same principle and even utilise similar circuit design. The ANC Timewave and MFJ devices are ridiculously expensive. Wimo's device is more moderately priced but Anton RA0SMS produces his device for $75 including shipping. The circuit employed is similar to the others and identical to Wimo.

I ordered mine via Anton's eBay sales. The stated 6 week shipping time was overly pessimistic and it arrived in under a month, with full tracking throughout its journey.

Apart from the obviously home-made control labels, the device is well constructed. It would be easy to smarten up the exterior.

Now, the use for which I wanted it: in my rural location I have nearly no noise except on 80mtrs from a power-pole transformer in a field adjacent to my property. It gives me S5 of noise. During rain, the noise is not present and my atmospheric band noise is S3. So I was hoping to use the device to phase out the noise by 1 to 2 S-points.

The critical component in the system, which determines how successful they operate, is the 'noise antenna'. It needs to inefficient at receiving the wanted signal, situated close to noise source, to receive as much of the unwanted signal as possible, and usually vertically polarised. I erected a spare HF mobile antenna at ground level on my property boundary as close to the power transformer as I could get it.

My first test of the X-phase was to deliberately generate some noise in the yard. I left an electric drill running. This gave me S9 of noise on 20mtrs. The X-phase took it out completely. So to 80mtrs - it wasn't hard to find the right combination of main antenna gain, noise antenna gain and phase to reduce the S5 of noise to a minimum amount. I managed a 1.5 S-point reduction. Testing in real-life on the CW end of the band shows that it makes the difference between reading low-level signals or not.