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Reviews Categories | Ham radio kits | QRP Labs Ultimate3 QRSS/WSPR kit Help

Reviews Summary for QRP Labs Ultimate3 QRSS/WSPR kit
QRP Labs Ultimate3 QRSS/WSPR kit Reviews: 11 Average rating: 5.0/5 MSRP: $29.00
Description: The Ultimate3 QRSS/WSPR Transmitter Kit transmits QRSS, Hell and WSPR slow- signal modes on any HF or MF band.

The kit is easy to build, with through-hole components only (no surface mount soldering). It comes with a pre-assembled and tested AD9850 DDS module, and one plug-in low pass filter module. Additional plug-in low pass filter modules are available for any of 12 HF or MF bands from 2200m to 10m. The kit can transmit on any frequency up to over 40MHz, and changing bands is a matter of plugging in the appropriate low pass filter kit to attenuate unwanted harmonic output.

A relay-switched LPF kit is also available, that allows the U3 kit to automatically switch between up to 6 bands in an operator-defined sequence.
Product is in production.
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N1BUG Rating: 5/5 Aug 18, 2018 14:21 Send this review to a friend
Great for 2200 and 630 meter bands  Time owned: more than 12 months
When I developed an interest in the (at the time soon-to-be) 2200 meter and 630 meter bands I learned about the Ultimate 3S. Many of the Part 5 experimental stations were using them as beacons on WSPR and other modes.

I ordered "the works" - Ultimate 3S, QLG1 GPS, relay switched LPF kit, low pass filters for 2200, 630, and 160 meters, and the optional case. Everything went together very easily and worked on the first try.

Originally I intended to use this under my Part 5 experimental license, but FCC opened the band for amateur use just as I was finishing up my station. I have been using it under my amateur radio license and having a blast! Using the U3S as an exciter driving a homebrew amplifier I was able to make a 2200 meter DFCW60 QSO across the Atlantic - a first under amateur radio rules from the U.S.

I also have the optional OCXO kit for the U3S but haven't got around to building that yet. On LF and MF, the U3S is very stable with the standard synthesizer module.
WD4ELG Rating: 5/5 Feb 24, 2018 16:50 Send this review to a friend
Fun, interesting, challenging build  Time owned: more than 12 months
Terrific support from Hans Summers who provides the kits. Excellent group message board with tons of help. Superior documentation on assembly and operation. I have three of these.
NU6I Rating: 5/5 Jan 30, 2018 20:09 Send this review to a friend
lot of fun and useful  Time owned: 3 to 6 months
I bought a Sotabeam WSPR but found it too cumbersome to change
bands and set the clock. You need a PC. I read about the Ultimate 3S
and bought one with the GPS.
Easy to use and no need to wait while listening to WWWV to synch
the clock.
This weekend I was seen on DXplorer at the german south pole
station DP0GVN (14150km) with a single 42' endfed wire as
inverted L. Not bad with 200mW and a simple wire antenna
from south California.
I have it on 30 and 20m. Still need to assemble the relay board
and the remaining band filters.
NE5U Rating: 5/5 Nov 30, 2017 19:28 Send this review to a friend
QRP Labs Ultimate3 WSPR kit - Loads of fun in a little box  Time owned: more than 12 months
I've built 5 of these kits and I've found them to be simple to build and loads of fun to operate. Especially during the low end of the solar cycle. The kit is well designed and has always worked the first time.

All of the kits that I built use the OLG1 GPS to discipline the oscillator. Only two of the 5 WSPR beacons are in a case at the moment. I'll get around to installing the rest in a case one of these days.

If you're new to kit building this is a great kit to start with and if you've been at it since the Heathkit days it's a fun kit to build.


KD8CGH Rating: 5/5 Sep 1, 2017 08:28 Send this review to a friend
nice kit  Time owned: 3 to 6 months
The kit went together easily and works well. I ordered mine with the QLG1-GPS module which self calibrates as well as setting accurate location and time.

At first I had no RF out. I got great help from the user group. It turns out that I didn't get all the insulation off a toriod wire end so no contact was made. It seems to be a common problem.
K7TP Rating: 5/5 Sep 20, 2016 16:25 Send this review to a friend
Fun and interesting  Time owned: 3 to 6 months
I just finished putting the Ultimate3 boards in the "official" enclosure. It looks really great.
The kit is enjoyable to build and interesting to operate. The first time I fired up QRSS mode I was heard in VS land from my W6 qth with only 80mW. That is not uncommon with qrss but nevertheless a thrill.
Kudos to the writer of the manual. As a technical writer of many years standing, I appreciate something that is as well-written as this construction pdf was.
KQ2RP Rating: 5/5 Sep 18, 2015 07:50 Send this review to a friend
The most fun you can have in Amateur Radio for $29!  Time owned: 6 to 12 months
I have built every version of the QRP Labs Ultimate Beacon kits, from single band Ultimate 1 through the current synthesized, backlit, feature-rich Ultimate 3S - they're addicting! The current version is by far the best and most versatile yet, allowing an inexpensive path for any kit-building ham to dip his/her toes into amazing low power modes like WSPR, QRSS, JT9, Opera, etc. Imagine having your callsign received on the other side of the globe with 150mW and a simple antenna! The design is well planned and the instructions are excellent. The flexibility and functionality packed into this kit compared with similarly priced kits is mind boggling. I can say without hesitation that this is the best $29 you'll spend in the hobby. Hours and hours of fun. Want to extend the fun? Pick up the band filter relay switch kit & GPS receiver kit, and add the custom case for an extremely slick end product. Grab an Ultimate 3S now (and one for a friend). Trust me, you won't be sorry.
KN8DMK Rating: 5/5 Sep 8, 2015 10:45 Send this review to a friend
U3S QRP-LABS, Lots of bells and whistles  Time owned: 3 to 6 months
Built the Ultimate U3S, 2-Si5351A Synth, 5-LPFs, Relay Board, OCXO/Si5351A Synth, QLG1-GPS. These are all quality fun kits. The U3S does all kinds of digital modes. If you like to build stuff and you have a spare antenna out back, this kit is for you. I have mine running 4 bands (3 WSPR) and 1 band (10M Beacon). There is allot of hands on experience to be enjoyed in these kits. They are very well documented and supported by Hans Summers. I had a lot of fun building them. And learned allot. And the price can't be beat.
K4JDG Rating: 5/5 Mar 16, 2015 08:46 Send this review to a friend
Great kit at a great price  Time owned: 0 to 3 months

I have been WSPRing for several months now and did not want to tie up my main radio, antenna, and PC. After research, I settled on Hans Summers Ultimate3s transmitter kit. Great Price! I got the 20 meter 3s kit and added the SKM61 GPS module and two extra BS170 transistors.

I am 61 and the circuit boards were a little small, but I got through it in good shape. I powered it up and was on the air quick. My only problem was a constant -3 to -4 Hz shift on each transmit. I contacted Hans and he was very quick with responses. Even after his suggestions, I still had a bad frequency shift.

Then I noticed a lad by the name of Bob (ZL1RS) from New Zealand had spotted me several times. That is over 8000 miles away, so I checked out his QRZ page. He also had Hans's 3s kit so I contacted him to see how he was making out. His reply had a fix in it to help with drift. It was simply to add a dummy WSPR transmission on 144 Mhz right before the real 20 Meters WSPR one. The 144 MHz output is almost totally suppressed by the 20m Low Pass Filter but it serves to 'warm up' the Si5351A synthesiser. This cut my drift to 0 to -1 Hz. Not too shabby.

I am getting around 1000 spots each day from all around the world. I had added all three BS170 transistors so I could could work high power ..... 1 watt.

If you have any interest in WSPR, I would start with your main radio and antenna. If you would like to continue then this kit will free up your main gear. It is a great and inexpensive little project.
KV4XD Rating: 5/5 Sep 22, 2014 12:12 Send this review to a friend
This kit simply works!  Time owned: 0 to 3 months
In a day I was on the air getting WSPR confirmations from over 5000 km away across the Atlantic Ocean with a random wire! I have looked and there is not a better kit for the money. It does CW, FSK, DFCW, Hellshreiber, SLOW CW, Call ID, WSPR and more, all without a computer.

Hans Summers, the creator, has done a fantastic job of documenting the assembly and operation of this kit. I love the fact that it is so extendable and customizable. You can get a basic one band kit and then add other bands and even a GPS later. If you need more power, there are spots on the board to add more BS170's. The kit also doubles as an accurate HF signal generator for bench testing and you can straight key with it. You could easily integrate it into your own projects.

Hans fully supports his kits and has answered my emails both promptly and thoroughly. If you are looking for a well designed quality kit to put the fun back in ham radio, you just found it. Thanks Hans!
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