| NK7Q |
Rating:  |
2006-04-07 | |
| Where did the noise go?!!! |
Time Owned: 0 to 3 months. |
I have a bad noise problem caused by high voltage lines right behind the house. On rainy or humid nights you can hear the crackling noise from the powerlines. This situation produces at least S-9 noise on the receiver, making operation difficult if not impossible. I hooked up the MFJ unit per their directions, not using the internal whip antenna but a dipole parallel to the powelines instead - this serves as my noise antenna. My Cushcraft R-7 vertical is the main antenna. During high noise periods, I simply tune the gains on the main and noise antennas separately, and then adjust the phase until the noise simply disappears. From S-9 noise to S-0 noise! Stations I could not hear just emerge from nowhere. A slight downside is that while I can hear them, they may not be able to hear me, but generally this is not the. Also, the S meter reading for the worked station will not read true because received signal strength drops with the noise. However, the signal to noise ratio increases, allowing you to hear the weakest of stations.
In order for this unit to work, some experimentation with the noise antenna is a must. You must put in some time on this to get it right, but it really pays off. Additionally, take MFJ's advice and connect a PTT cable from the tranceiver to the MFJ. Then there will be no worries about overloading the circuitry during transmit.
All in all, this is one impressive performer. It will generally only tune out one type of noise, dependent on the noise antenna used. Some noise situations may not be fixable. I am now happily operating on nights where this would have been impossible before. As I have only had the unit for a few weeks, I cannot comment on long-term reliability. So far though I am very pleased. |
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| VA7CZ |
Rating: |
2006-02-05 | |
| Indispensible aid |
Time Owned: 0 to 3 months. |
I got my 1026 new a bit over a month ago. I live in a noisy, urban location and use a mobile antenna from an apartment balcony as well as various odd wire antennas. The 1026 is a real trooper at removing the largest single source of noise on any given frequency. Don't expect too much from one of these, as, being an antenna steering device, they can really only null one or two directions at a time. But if you're plagued by loud single-source noises, this can take them right out.
The only drawback was that the supplied whip did not fit the supplied mount (inside the unit). No big huhu, though, I just wedged it in place with the plastic cap of a ballpoint pen and it works fine.
My IC-751 has a jumper for inserting a transverter or using a separate receive antenna. I connected the MFJ 1026 into the rig there, so as not to have to worry about whether its antenna switch would be adequate. MFJ does recommend you either do that or hook its push-to-talk up to a DC PTT line from your rig.
All in all, I can do a lot more hamming with it than I could without it. |
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| W7MY |
Rating: |
2005-12-08 | |
| Outstanding! |
Time Owned: more than 12 months. |
| I have used my 1026 for about 7 years. I use it exclusively for digging out the weak ones on 160 meters. I live in an urban environement with lots of emissions from all sorts of electronic gadgits. I can say that I would pobably not be able to operate with out it. I use it with a 160 dipole and a 160 meter vertical which are spaced apart about 25'. The dipole is only up about 30' and the vertical is a 70' top loaded affair. I am able to null most of my received birdies down 30-50 db! I have never tried the sense antenna and believe it to be useless. |
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| former_AE6CP_LH |
Rating: |
2005-12-07 | |
| OMG! it Works!!! |
Time Owned: 0 to 3 months. |
Okay so I did what many of us did the first time I got this thing home... I tore open the box, threw it on the desk, plugged it in, turned it on and started twisting all the knobs back and fourth as fast as I could....Nothing.
Okay so after I realized I couldn't return it because the box was all torn up, I figured I'd give it one last try but this time I'd read the manual first.
The noise level at my home is usually between an S8 and S9+, it's not a hum or pulse noise, just a loud white noise like a TV makes if you take away the cable or antenna.
My antennas consist of a remotely tuned 40m mag loop and an end fed 20m dipole in the attic above my third floor apartment. I connected the dipole to the main antenna connector and connected a 20' piece of wire to the aux antenna connector and threw it over the door frame.
You can learn all about how it works in the manual or online but here's a quick start guide to hearing it's effects right away.
1)connect your 'main' and 'aux' antenna
(don't use the tiny internal whip and choose an aux antenna that's comparable to your main antenna so they both hear the "same" noise)
2)plug in remote TX line (don't use internal RF sensing circuit)
3)Make sure the power button is off and connect the 12Vdc.
4)connect station ground.
5)Turn all knobs fully CCW, 'preamp' button 'off', 'phase' button to 'normal' and 'Freq' button to 'high' if you're on 30m or above or 'low' if you're on 40m or below.
6)Turn on your tranceiver, pick a frequency and take note of the noise level on your S meter.
7)Turn on power on the 1026.(Rx will get quiet)
8)Turn up 'Aux antenna gain' until noise just hits it's normal S reading on your meter (the same level noted in step 6) note position of knob then turn it back fully CCW.
9)Turn the 'main antenna gain' until noise just hits exact same level, leave that knob where it is.
10)Turn the Aux antenna gain back to the same position in step 8.
11) Slowly rotate the Phase knob until the S meter reads zero!
Yes I said zero, My radio is an FT-857, not quite a K2 on RX (God I miss ol' #2737) but the S-meter went from S9+ to S Zero and there was no effect on real signals.
I don't understand why this isn't part of every big name rig.
73,
Larry |
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| WB8YQJ |
Rating: |
2005-09-26 | |
| MFJ-1026 - Cures the worst RFI |
Time Owned: 0 to 3 months. |
I bought a new Whirlpool "Duet" front loading washing machine and it put S7 to S9 noise across the 20 meter band at approximately 10 khz intervals.
The S9 hash noise is accompanied by a strong BUZZZ at many points on the dial. Rig is an OMNI VI+, antenna is a GAP Eagle, and the noise antenna is a fan dipole fed with twin lead and installed in the attic.
The noise is cancelled out completely. All I can hear are traces at a few points on the dial if I listen and tune the transceiver very carefully.
You judge for yourself what that would be worth to you.
It also worked to phase out RFI from a 27" SONY TV in the shack, that application didn't even require the external noise antenna.
Remember though that the device only tunes to a single noise source so it's the washer or the TV but not both.
The MFJ box has the usual marginal fit and finish. I hate repainting a -new- item! But the PC board inside is a quality (SMT) unit and the switches and pots are good too.
I'm amazed that some of the early reviews have watered down this product's rating, but that's the nature of these reviews for many products it seems.
If you take the time to setup this box properly, it will work wonders for you.
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| G7CNF |
Rating: |
2005-01-30 | |
| Patience is a virtue..... |
Time Owned: 0 to 3 months. |
I read the reviews here prior to buying the 1026 with some interest and tentatively bought one. My first reactions were blimey, it's rubbish....BUT.... Patience is a virtue, and now? There is no way I could ever consider venturing onto HF without it.
I have two main antennas, a G5RV full size for the lower bands, and a home-made 1/2 wave folded 5 bander dipole (confined field) for 20-10. The G5RV often sees a noise floor of S9 at this location, and now it is VERY rare for me to have a noise floor higher than S3 and most of the time S0-S2 with the 1026 tuned up.
***The key to this chap is getting the noise antenna right***, and of course using the tnx line for TX, forget the internal sensor or you'll just smoke this unit!
There is nothing, NOTHING, I can't peak or null. Noise from my switch mode PSU, computer, broadcast stations, other hams, QRM (to some extent, but need practice). You must be patient, learn how to use it and get your noise antenna right. If you are not prepared to do this, don't buy one.
Don't buy the gear and take it straight out of the box and expect a cure-all. The gear is only as good as the operator's technical understanding of the application. If you don't understand the issues of phasing an antenna array, how can you expect to get the best from a device designed to do exactly that?
For the record my noise antenna is a 6m piece of coax. That’s it. Nothing more. No more is needed.
Good DX and 73’s.
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| NJ6F |
Rating: |
2004-11-14 | |
| Works Great 1025 Review |
Time Owned: 0 to 3 months. |
This one has the hole for the external antenna on top but coves with hookup on back as well.
YES IT WORKS amazingly well. S9 noise cancelled down to S1 or less, on hiss and funky electrical transformer noise and even QRN.
Yes, if you take the time to hook it up right and read the directions, it will work for you as well. Set up both antennas in the same polizarition.... horizontal typically and make sure both antennas are receiving some of the signal. If second antenns does not receive a decent signal, then don't expect it to work or cancel signals.
Basically you max out on the second antenna WITH SAME POLARIZATION AS FIRST ANTENNA , and then add a little bit of gain from second antenna and vary or shoot for a null or peak by shifting the second antenna knob and looking at the noise on the meter. You basically want to achieve the null while cutting the max gain of primary antenna but what you get is severe noise being wiped out.... shut off unit and you will see difference. or flip the phase switch for a max signal peak or minimum noise.
*** It works ahead of your radio so no AGC is activated, and it will do better than a noise blanker will do but without the audio distortion...amazing.
Yes sometimes there is not much noise it will not do anything noticable for you if condx are quiet but if you put your phones on and intently listen you will even see improvement with no bad conditions just improved noise floor.
Get the 1025, the antenna on the 1026 is not worth it.
Look at your s-meter while you do these things and you will see the difference. Sometimes it is so good but the phase shift doesnt seem to make much difference because noise knockout is so broad but when you shut it off or change phase you can notice a major difference. Tune the band for some received noise in areas of the band where there is noise clusters. Then activate this baby and go for it.
Yes if you are some impatient complainer that doesnt take the time to read or listen to the unit when hooked up correctly, you might not see the result and just surmise that unit is bad which is not the case.
That is how they get on the internet....they all work.... it is just the impatient person that makes us all lucky to see one on eham or ebay.
I got mine for $67 NEW in the box off ebay.
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| M0NKD |
Rating: |
2004-05-24 | |
| Does what it says on the Tin |
Time Owned: 0 to 3 months. |
For a number of years I'd heard of various manufacturers producing gadgets to reduce noise by phasing two aerials against each other. I didn't realise MFJ did one until recently. I read the reviews and then the manual very carefully and was conscious that the use of external PTT switching is more or less essential to stop the unit frying. Installed but checked the internal relay was switching from the rigs linear PTT connector, before putting any RF through-it. It works, infact it works brilliantly!! Changed internal connectors to allow pre-amp to be used on external noise antenna rather than the built-in whip. 80m used to be a nightmare, but with practise I can null-out S9 of noise to S1 or less!!
There is a 'but', the noise antenna is protected by an internal 12v 50mA bulb. This is NOT switched out by the PTT relay which means if you are running high power and the noise antenna is too close to your main antenna it will pop the bulb. I've now installed a bulb holder and have a few spare bulbs just in case.
Overall, care needed in installation, patience required to configure and MFJ's not uncommon not quite designed as well as it could be. It still gets 5/5 though simply because it does what it says on the tin:- Deluxe Noise Cancelling Signal Enhancer. You can hear signals which are simply utterley inaudible without it! |
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| XE1CT |
Rating: |
2004-03-17 | |
| Great device |
Time Owned: 6 to 12 months. |
I have had this unit for few months and let me tell you that it has solved my S 8-9 powerline noise, 130KV about 30 meters, It works wonderfully but an auxilkiary antenna is a must, I use 15 meters ground plane as noise antenna.
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| K5TED |
Rating: |
2004-03-07 | |
| woks ok |
Time Owned: 0 to 3 months. |
In hopes of helping with some serious local noise from PCs, a neighbor with a diathermy machine or depillator(not sure, but it's NOISY) and a noisy transformer or two, I purchased the 1026 on eBay, in brand new condition with box, manual, antenna, pigtail for $125.
After reading the reviews, I determined it was going to be a coin-toss at best. The result was much more impressive than I had expected.
This installation is for SWL only, so I don't have the issue with the RF sensing and such.
What I found is that I am able to almost completely eliminate local PC noise with just a few turns of the knobs. The neighbor's diathermy machine was trickier, but with the 1026, I could make totally unusable signals into very listenable signals. As for the noisy transformer across the street, the 1026 did wonders as well. No more sputtering and crackling. Gone. Completely.
Yes, some signal loss occurs in the tuning process, but S/N goes way up.
Overall, I'd say the box does what it is advertised to do. There are some problems, as noted elsewhere in the reviews, with interfering skywave signals polarity changes. I can say, though, that a good example is the ability to almost completely eliminate the jamming signals on Radio Marti.
My listening post is in S central TX. The box does well on about 50-75% of the instances where I need to sort out co-channel stations, and almost perfectly when killing an adjacent station signal. One need simply tune to the offending station, null it out, then go back to the desired frequency and tune for cleanest signal. It may end up being weak, but it'll be clean enough to read.
On MW, one evening for example, I was able to briefly sort out local KLUP 930 from WKY 930 in OKC. I did not do any modification to the 1026 for MW. It does drop off dramatically in effect below 850kHz
Not a bad deal, and worth the investment.
I have antenna restrictions, so I'm using a 10m wire for the noise antenna, and a 10m folded dipole for main. The antennas are about 20ft. apart. The preamp, set at "moderate" gain, is enough to bring the wire up to the dipole signal strength when needed. On some bands, of course, the wire wins without the pre. The ability to phase the antennas together does provide some extra gain on certain signals, but not consistently.
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