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Reviews Categories | QRP Radios (5 watts or less) | NS-40 Class E Transmitter by NM0S Help

Reviews Summary for NS-40 Class E Transmitter by NM0S
NS-40 Class E Transmitter by NM0S Reviews: 12 Average rating: 4.8/5 MSRP: $30 (DX $33)
Description: Kit designed by David Cripe NM0S, and made available by 4SQRP Group. The NS-40 Transmitter is an upgraded version of the overall winner in the FDIM 2008 Homebrew Contest. It is a truly unique QRP transmitter design. NS stands for No Simpler, so this is the No Simpler 40 Meter Transmiter.
Product is in production.
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KD8IIC Rating: 5/5 Aug 21, 2017 23:27 Send this review to a friend
Great Little Powerhouse.  Time owned: 0 to 3 months
Got mine in the mail today and it went together quickly.
The smaller transistor orientation is the flat side facing towards the BNC connector.
The pix of it is blurry, other than that it is a lotta fun and mine is putting up 6 watts with no heating the output. Loading a full wave open wired doublet.
1st CQ answered 850 miles was away with QSB/QRN 479 RST.No chirp and no drift.

Hope he makes more of these. I got last one!
W2DLC Rating: 5/5 Mar 7, 2017 13:59 Send this review to a friend
Clean Signal From Mine  Time owned: 0 to 3 months
NM0S is selling a few kits on eBay, and I was intrigued. I sent for one and it came in about three days. It took me about an hour to carefully put together. I tested it several times while listening on my receiver, and the signal is clean. I sent a couple of CQs at about 1800hrs, and K2QU in New Jersey came back and gave me a 589. I'm looking for a box to house it to make it look a little nicer now, but otherwise, I'm very happy.
KD7RDZI2 Rating: 5/5 Jan 5, 2015 11:19 Send this review to a friend
powerful  Time owned: 0 to 3 months
Is this a qrp? I get about 7W at something 13Vdc. Others have reported over 10w!! To protect the keyer I used the simplest interface with a single TIP42G. My first qso was a bit chirpy, I could hear it on my receiver. Then I moved the plastic case in such a way that spirals were not too close to metal surfaces. The note is now a good one. It's really incredible how cold the final is! Building this kit is just a pleasure. No toroids to wind just a few components. A really well designed transmitter. I wish they could offer a 20m and 30m versions.
KU4UV Rating: 5/5 Dec 4, 2012 12:34 Send this review to a friend
Fun and easy kit that actually works!  Time owned: 0 to 3 months
I ordered my NS-40 last Tuesday, and it arrived on the following Monday. The whole kit, short of the needed wires for the antenna, key, and power hookups, took about 30 minutes to complete. When I powered up the transmitter, it showed around 10 Watts output power. I played around with the kit last night, but wasn't able to make a contact just yet. Overall, I give the kit a 5. One thing I noticed that concerned me though was that the kit was mailed in a padded mailing envelope that had a nice 1 inch gash in the side of it. Luckily, all the parts were still there, but I wish that the kits could be packaged a little better. I know the kits are shipped by volunteers, but I would gladly pay the extra cost to have the kit shipped in a little better packaging.
One other thing, one of the the capacitors was much larger than the other components, and the leads were not able to go through the tiny holes on the circuit board. I ended up just tack soldering the capacitor to the board, and so far everything works fine. I don't know why this particular part was so much larger than the others, unless they ran out of that particular item. I may change the part to a smaller capacitor sometime. Also, the components were shipped in a Ziplock bag. There is a note in the instructions (which you have to view online) that warns about the danger of static discharge to the MOSFET transistors. Not sure why the Ziplock bag was used, but no problems so far. Other than these few minor gripes, I recommend this kit.

DAVER Rating: 5/5 Sep 29, 2011 08:58 Send this review to a friend
Great Kit  Time owned: 3 to 6 months
Not much to say that hasn't been said... Simple isn't the word for it, only a few parts. Performs great (just over true qrp with my gell cell at full charge). Has taken plenty of abuse as well regarding pushing into bad loads and no damage to the final at all. Only tricky part is you may need to whip up something to use a paddle with a keyer b/c it has a high current on the keyline.

I use it with the Magicbox (nicest designed kit I've ever seen) and the SS-40 receiver and am very happy with the station. If I get overly ambitous I may pursue getting a VFO dds hooked to the station for expanded coverage.

With the NS-40 it comes with just a crystal (around 7030) but also has some thru-wholes you can use to add C/L combos for a simple VFO of sorts. Or you can ake the crystal out and just add your own VFO utilizing multiple crystals and whatnot.

I love the 4states kits and like I said before, it is my 40m CW station.

WD9F Rating: 5/5 Sep 11, 2011 17:52 Send this review to a friend
Amazing QRP Xmtr  Time owned: 3 to 6 months
This is a simple to build project with about 15 parts. The build directions were perfect and all parts were provided. I finished mine in about 45 minutes and it worked FB. I did have a chirping problem with a 13.8V AC supply but when I backed off and used a 12V battery, no problem at all. I get great reports, it cranks out a solid 7W at 12V and I've worked 16 states with it. I'd recommend it to anyone. It's really fun.
AE4GM Rating: 5/5 Jun 14, 2011 15:08 Send this review to a friend
VFO for NS-40  Time owned: more than 12 months
I finally got VFO control of my NS-40. I had tried my Heathkit HG-10 before with no luck. This time I tried keying it in SPOT position. It worked!!! I'm getting about 5 or 6 watts of great sounding CW out of it. Eureka!!!!!!! To go back to receive you have to put the VFO back in the normal vfo position off of spot so the tone does not interfere with the receiver.
KF7DMY Rating: 5/5 Jan 31, 2011 18:31 Send this review to a friend
It WORKS!!! but I still wish it'd be plug-n-play..  Time owned: 0 to 3 months
My NS-40 works as it should now. Initial problem of chirping was not because of poor soldering job but has something to do with voltage regulation. The circuit works even with 9 volts power supply. I am using a regulated 13.5 volts and was extremely chirpy until I added a higher value to C2 2.2uF to be exact since that was all I have in my junk box. I'm pretty sure the value I used could be a bit smaller.
I am happy with my NS-40. I gave it 5 for its simplicity.

Thanks to AE4GM for the quick help.



AE4GM Rating: 5/5 Jan 29, 2011 12:08 Send this review to a friend
Chirpy signal  Time owned: more than 12 months
I had an initial problem with good contact on the crystal through hole soldering connection. If you are only getting 5 watts and it's chirpy you should look at that and other solder joints. I get just over 9 watts out of mine and it works very well.
KF7DMY Rating: 3/5 Jan 29, 2011 00:35 Send this review to a friend
Not a plug-and-play transmitter  Time owned: 0 to 3 months
This is my first QRP project and I'm not very happy with the performance. It is very chirpy. I was able to get 5 watts out. But the quality of the cw is so ugly. I would hold on to the NS40 until I can find some help. If the other hams like it, then there must be something good about it. Al, KF7DMY
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