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Reviews For: NS 3 KHz Roofing filters for FT-2000/FT-950

Category: Filters, RF: bandpass, duplexer, lowpass, highpass, RFI/EMI

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Review Summary For : NS 3 KHz Roofing filters for FT-2000/FT-950
Reviews: 37MSRP: USD $304.80
Description:

3 KHz Roofing filter modification for the FT-2000 & FT-950
THE NS FILTER MOD DELIVERS!
+20 db typical increase in IMDDR3
2.4-2.6 KHz -6db bandwidth (typical)
Product is in production
More Info: http://www.ac0c.com/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00375
NE7X Rating: 2010-11-26
Worth the money !!! Time Owned: 3 to 6 months.
I added the NS 3KHz roofing filter to my FT-2000 and "WOW" what a HUGH improvement difference!!!

Tuning the receiver to a clear unused frequency, when I rotate between the 15KHz, 6KHZ and 3KHz roofing filters, I can very clearly hear the noise passband difference. This was not the case before with the stock 3KHz roofing filter. There was no notable difference between the stock 6KHz and 3KHz filters. I can also clearly hear the difference when receiving SSB signals. The audio has a nice clean "pinched/narrow" sound to it.

I also add the DUM sensitivity mod. This mod eliminates the reduces DMU gain when switching to 6KHz and 3KHz filters. For more info on this mod, visit: http://www.ne7x.com/PPS/FT-2000_DMU_Mod.pps

Thomas NE7X...
Website: http://www.ne7x.com

PA0LUX Rating: 2010-11-26
A boost in performance Time Owned: 0 to 3 months.
I bought this filter because I would like to own a FT-2000 with the best possible specifications. And also because I like to be busy with my soldering iron. Installing this filter is not really difficult, as long as you take your time for it and do not panic too easy! After the install I found that the set had dramatically improved behaviour, compared to the stock filter. You can now really hear that a filter is present and that it works like a 3 kHz filter really should work (but never did in the FT-2000)
I highly recommend it.
PA5CA Rating: 2010-11-26
Best purchase for the FT2000 Time Owned: 0 to 3 months.
I was one of the main complainers about the FT2K. (own the rig since 2007) From the first moment I listen to the receiver I noticed here poorness.
The PEP update finally made the DSP work, but the RX could not stand strong nearby signals! I'm member of one of the most active contest groups in the Netherlands www.pa6z.nl The best environment to test a receiver. It turned out that the FT2K could not match the FT1K mark V ( all x-tall's installed) receiver.
Than the NS filter came available.. and I'm impressed by the performance improvement of the FT2K main receiver.
The DSP works far better.. less band with to process, The VRF seems to function as designed.
So the FT2K for the time being will be a keeper for me.

The annoying thing is that a guy's like Jeff had to cure the FT2K RX where Yaesu have messed up so badly.
So I'm gratefully that I came across Jeff AC0C ( www.ac0c.com ).
The FT2K is not perfect even with the NS filter but it now became a reasonable TRX. Thanks to Jeff and NS effort.

I have up-loaded a video impression, it is about the comparison between a stock and NS modified FT2000. You will notice a huge difference between the two rigs. Please note there is an 50Hz offset.. (my fault) but this does not influence the video result.
http://video.yahoo.com/watch/8514814/22808248

Enjoy HAM radio...
73 Frans. ( http://groups.yahoo.com/group/FT2000_new/ )

WB8YQJ Rating: 2010-11-24
Amazing Upgrade Dec 2010 Update Time Owned: 3 to 6 months.
When the FT2000 was rolled out by Yaesu in early 2007 it had two major shortcomings. The firmware was not ready and neither was the narrow 3khz roofing filter. Following manufacture the firmware was eventually corrected, until the "PEP" update resolved the vast majority of the DSP problems. However the 3khz filter could only be made to function by Yaesu's cobbling the filter circuit enough to show the 3khz spec under lab conditions.

In practice, the 15khz, 6khz, and 3khz roofing filters are actually 15khz, 7khz, and 7khz wide. These stock filters are 69mhz filters and the reason Yaesu could not get the 3khz filter to work was because they hoped a cost effective 3khz at 69mhz filter would be available at production and it just did not happen. Jeff Blaine later found the filter they were unable to locate using his commercial connections in the RF industry.

The cost of the NS filter was $300 when I purchased mine, for me it was the best $300 I ever spent on a transceiver accessory. I don't care about specs, the FT2000 has big signal handling that is sufficient for my antennas and bands in stock configuration. However, Rob Sherwood arranges his list of receivers in "Dynamic Range Narrow Spaced" order and FT2000 had a weak preliminary test due to the firmware revision and some other factors.

So the FT2000 results are pages down the list from the top performers which show better than 90db. The FT2000 is listed among the weaker receivers at 63db. I have used some of the radios in that group and can say my (PEP firmware upgraded) FT2000 by no means had the AGC pumping problem, desense, or some of the other problems I have experienced that is common to the group of transceivers listed around it at 60db. That having been said, the NS filter upgrade would move FT2000 well up Sherwood's list if he were to retest it, I am told approaching 90db.

Even the popular contest rigs FT1000MP and FT1000D were only upper 60's performers. Nothing special, there are many other factors that matter more with receiver design but if you have the NS filter - your FT2000 spec is Orion class.

I made some observations in the day to day operation of FT2000 with the NS filter, these were posted to the Yahoo reflector and are detailed in the text below. The executive summary is that receiver performance is greatly improved for phone modes using the NS filter, even when there are no BIG signals on the band. There is a recording, listen yourself. The quiet spots are the NS filter. It took no special conditions to setup the test, and it can be reproduced easily.

The NS filter itself is beyond large in comparison to all the circuitry around it, yet there is an area for it to fit which is close to the connection points and where the filter case does not stress any of the internal components.

I am at a disagreement with some others about the relative ease of installation, it was one of the more difficult things I have ever done, due to the SMT sized solder pads that the filter coax is connected to. There are only 4 connections to FT2000 but they are smaller than a SMT resistor and you are trying to get coax braid attached there. Strain relief is a major factor, the wire I used is thin enough to break when it is pulled on rather than lifting the FT2000 PCB trace. The modification is reversable in practical terms, restoring the trace that must be cut with a hobby knife would actually be much easier than making the original cut. It is hard to see if the channel is clear of debris after the cut because of the trace and the clearcoat debris after scraping a path. There is also a SMT resistor that must be removed. The most challenging part of the job is connecting one wire at the PCB which is overhung by a transformer can. It is a very small margin, magnification and bright light is a must.

See the photos on the Yahoo FT2000 group to get some idea of this. I have built SoftRock and other SMT, which in comparison was a breeze, I ended up using smaller wire for the job than you will see in the Yahoo FT2000 group photos.

Here are some comments I made on the Yahoo FT2000 Group about the NS Filter:

- Listening on USB, 14 mhz, no signal, antenna connected, IPO activated. DSP bandwidth set at 2400 hz. Theoretically there should be no difference when toggling through the ROOF positions, yet, I can detect the 3 khz position in a blind test toggle through all positions, NS is more quiet. Remove the antenna, and the difference is no longer detectable.

- In my tests under many conditions, the FT2000 DSP (WIDTH control) will faithfully restrict bandwidth to (the same) 2500hz just as the NS filter does, but the detected audio from the NS filter is greatly desirable to the output of the DSP algorithm fed by the stock roofing filter. Listening fatigue is reduced.

I've tried all the bandwidth options from SCAF filters to DSP to narrow dedicated SSB filters - the combination of this NS roofing filter and the YAESU DSP to provide NOTCH, NR, etc. is something special.

It really makes me wonder if the stock FT5000 DSP, having the better ultimate selectivity that you would install a NS filter in FT2000 to approximate - sounds as good in the end.

http://www.zerobeat.net/wb8yqj/FT2000NS.wav

This recording was made using FT2000 with NS Filter under optimal conditions on 10 meters 28.400 to display the improvement of the NS filter in the FT2000 audio. The improvement is more difficult to demonstrate for detection of weak signals in contest conditions, but it is obvious as well.

The original test (not in this recording) was using the FT2000 IF DSP dialed to 4000hz and yes when the 2.4khz NS filter is selected, a great deal of unnecessary noise is removed and yes this is very obvious.

However in this recording the DSP bandwidth is selected at 2400hz and this is of course -inside- the NS filter bandwidth. Assuming no large signals on the band, there should be no difference in the detected audio because the roofing filter is only supposed to eliminate signal overload.

However it is obvious in this recording that the FT2000 DSP benefits greatly from the NS filter (stock filter garbage in = garbage out). The difference you hear is not due to attenuation, in my installation there was no loss from the NS filter compared to the stock filter.

The NS filter is also greatly more effective than the stock roofing filter in noisy band conditions, however this recording was made on a quiet morning 9am in Southern California. The beep that is heard is the R.FLT selections, counting the fourth beep and you hear the NS Filter. First is with no SSB audio, then the next cycle is with some USB audio.

What you cannot hear in the recording is that the fidelity of the NS filter is quite good (pleasing) even when compared to wider DSP settings using the stock roofing filter.

On CW, I can see no improvement with the NS filter under casual conditions, however under big signal conditions the filter will keep the receiver from falling apart from the band bullies. ;-)

I don't know what the rate of distribution of this filter is, but I do know that it took almost a year for all the hard work to be done by an all star technical team for this window to be open now for however long it stays. If anyone is sitting on the fence for any reason other than availability of $300 bucks - I would suggest in the strongest terms that they get off the fence and take advantage of it.

VE3MSC Rating: 2010-11-24
Stunning performance Time Owned: 0 to 3 months.
This is the best investment I've made on this rig. Compared to other accessories, its less expensive than a uTune unit and works fabulously.
Unlike the factory 3kHz filter, there is a big difference between the NS 3kHz and factory 6kHz filters. The Network Sciences filter has much steeper sides, and eliminates nearby signals. I have a FTdx5000 and ran the two rigs side by side for about 2 months, and it brings the FT2K dramatically closer to the Gold Standard. Whether you run digital modes, CW, or phone, it eliminates nearby signals. Installation is straightforward but not for the faint of heart, as you remove a surface mount component and solder in two bits of miniature coax. Count on 1-2 hours to open the rig and do it right.
OH6MW Rating: 2010-11-12
AC0C NS roofing filter installed and working fb Time Owned: more than 12 months.
This filter is excellent, Thank You very much Jeff.
I recommend this to everyone, makes your ft-2000 even better. Buy one and test yourself, satisfaction quaranteed.
I don't have smt experience, but no problem. Vy fast installation by a friend, tnx Juha agn.
By installing this filter into you FT-2000 you get FT-5000 performance with better rig ergonomics with minimal costs.

AC0C Jeff,thank you ever so much, You are doing fb job !

Really looking forward CQ WW cw contest, cu in test.

73 Ari OH6MW
W6GDK Rating: 2010-10-31
Worth the wait and the cost Time Owned: 0 to 3 months.
Converts an ineffective stock 3 KHz roofing filter on the FT2000 and FT-2000D to a 2.5 KHz filter. Much narrower than the stock filter. Installation is straight forward, but some SMT skill is required. Well worth the cost. FT-2000 compares favorably to the IC-7800 and FT-9000 for the 2KHz spacing DR3 test.