| G6HSM |
Rating:  |
2018-06-15 | |
| good basic QRP radio |
Time Owned: 0 to 3 months. |
Purchased as an unstarted second hand kit on EBay and finished in a week of 1hr evenings, worked first time but power a bit low. Experimented with the drive-pa balun and improved it to 6w on 40 and 5w on 20. Checked with a two tone tester and calibrated attenuator/analyser, IPS OK less than 28dB. Throw the speaker away and replace it with a small speaker unit from a PC just double sided taped into the case. Uses the case as a cavity and sounds fine, plenty of volume. I tried other Mylar speakers with dissapointing results. Second contact to NY2PO on a 1.3mtr whip with 7t counterpoise in the back garden. So very happy with the kit, though the driver transistor popped during testing baluns, easily swapped (2SC3357). Probably my fault anyway!
73,s Mark G6HSM |
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| KK6VHP |
Rating:  |
2017-06-22 | |
| Good idea. Horrible execution. |
Time Owned: more than 12 months. |
| I had such great hopes for this handheld transceiver. Within the first day of use the LED began freezing. I was able to "fix" it by shaking the transceiver, though ultimately I had to open it up and attempt to re-set the ribbon connections. I never really cured the problem. Then the slider on/off switch sheared off by brushing against the carrying case. Others have touched on the many problems: e.g., the speaker sucks. There has been a cascade of other problems. Worst of all, no schematic. The lesson is to never buy something without a schematic. I think the DDS VFO has major issues. I'm learning a lot trying to reverse engineer my best guess of a schematic. Customer service is non-existent, especially now I'm past the warranty. I've got a lemon. I noted that the radio is no longer sold, so that's a good thing. |
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| KB0SFP |
Rating: |
2017-04-12 | |
| Very good idea, poorly implemented. |
Time Owned: 6 to 12 months. |
Unlimited distribution of the below material is authorized & encouraged.
First a little about myself. I am an extremely active operator of QRP portable equipment. A large amount of my near daily operation is picnic table portable, or pedestrian mobile/portable. In this pursuit I own & operated over a dozen radios ranging in value from a couple hundred dollars(like the Youkits), to several thousand dollar commercial & military types. So I'm not a novice who just opened the box, and looked at the radio, to arrive at the below conclusions. I have some experience with the radio, and it's use.
My observances to this point of the TJ2B. This is the late issue variant that is currently in production(40,20,17m transceive):
TX audio is acceptable according to on-air reports as long as you are using the supplied external mic. The internal mic is reported as "mushy". I must wonder why as both mics use similar electret type elements.
The radio does not even approach 5 watts on any band 40-17. 3 watts is about all it will do.
The internal speaker is worthless! It does not emit enough audio to hear anything unless you are holding the radio to your head. At first I thought the radio to be defective, then I hooked up an external speaker and was shocked by the amount of audio output. I must assume the fault lay in the lack of quality of the internal speaker. As there is no schematic to work from, trouble shooting difficulty is greatly amplified. I haven't been able to get the case apart to attempt an investigation of the problem. I have some nice mylar speakers that would fit if I could get the case open.
Removing the boards from the cabinet proved to be so difficult that I gave up fearing that I would break something.
Why not use a speaker/mic? The connections are already there, just apparently not used. I'd modify it myself but for other restrictions detailed in this post. No provision for the use of a speaker/mic(or headsets) greatly hinders the versatility of the radio. The worthless internal speaker, and mushy internal mic could have been ignored had this simple, and basic provision been implemented.
I question the use of BNC antenna connector, and no ground post? The BNC connector is a very poor antenna support. As this is a hand held radio we can assume it will have a whip antenna of some sort connected to it. Whip antennas for the HF bands tend to be rather long. It would have made far more sense to use an SO-239. A simple BNC to PL-259 adapter could be used for those commercially available HF antennas that use a BNC connector. I was going to change out the BNC for SO-239 but again, stopped for fear of breaking something trying to get it opened up.
Anybody who has ever operated portable, or pedestrian mobile, knows the necessity of a counterpoise, but the radio has no place to connect one. Again, I could have installed one myself, but for the inability to remove the case. Perhaps there is a trick that somebody can inform me of? For temporary I mounted a male spade connector via an existing cabinet screw.
There is a bar graph LCD display that deflects nearly full scale with TX audio. I have no idea what this is supposed to indicated as it will even deflect full scale on bands that the radio does not transmit on.
The lack of available schematic and parts placement guide prevent attempts at repair or modification. I have a couple of tiny voice processors that I'd like to install, as well as a reflected power indicator, but I am very hesitant without knowing what I'm hooking in to. The attitude held by Youkits on this subject seems to be universally held by chinese manufactures and this, combined with a total lack of factory support, have prevented me(and I'm sure others) from buying equipment of chinese origin.
Performance:
The receiver performance is acceptable but severely hindered by the poor audio of the internal speaker. RF output is also acceptable but not what is advertised. TX audio is also fair provided you are not using the internal microphone.
Summing up:
The quality of manufacture appears to be pretty good. The boards(what I could see of them) look quite good.
The internal battery is a wast of valuable space that could have been occupied by such things as a voice processor, metering(RF/SWR), antenna matcher, more band coverage, etc.
The battery could have been contained in an external clip on battery box as is done on most commercial & military radios. This would have greatly enhanced the versatility of the set, & allowed a number of different battery options.
Limited band coverage. While I do not expect all ham band coverage from such a radio, I see no reason that at least 60 & 15 meters could not have been included without any additional circuitry in the radio. The existing filters for 40 meters would have also worked for 60 meters just as is done on all Ham rigs today. And 15 meter filters could have been used for both 18 & 21mhz. To expand on this, 12 meter filters could have been used that would have allowed 17, 15, and 12 meter operation.
There is no reason I can think of that prevented the use of a speaker/mic rather than the supplied external mic. In fact, it appears that this mic actually started out as a speaker/mic & they just neglected to install the speaker, right down to the rubber stopper where the earphone jack would have been.
Were I the designer, I would have omitted both the internal speaker, and mic, in favor of external audio devices. Again, this would have allowed more internal space for other features, and with a more substantial audio connector, versatility would have been greatly enhanced,
The refusal of chinese manufactures to supply a schematic, & parts placement, for their products should in itself discourage everybody from buying-china. This combined with the total lack of product support have already stopped me from buying a number of otherwise attractive products recently introduce to the US Amature radio market.
There is a Youkits Yahoo group that supposedly is monitored by Youkits factory personnel. I have yet to see even the simplest of questions receive a response.
It's a shame! Very good idea, poorly implemented.
Dennis Starks
Military-Radio-Guy
KBØSFP
HFpack/Milpack, Monitor all: 3996usb, 5357usb, 7296usb, 14342.5usb, 18157.5usb, 29.4fm, 51.0fm |
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| W6KLD |
Rating: |
2016-04-11 | |
| Works well, fewer bugs |
Time Owned: 0 to 3 months. |
I had specific portable needs and the TJ2B covered the bases. Rig arrived this past Friday. Well shipped/secure. A transplant to South Dakota, I made numerous contacts to my home state of Ga. for the QSO Party weekend averaging 5 watts out. Best signal report I received was a 5/9 from central Ga. and into an MP1 mounted on my desk!
Tuning is a learning curve but becomes predictable.
The 2016 version no longer supports wide band coverage and as a result, no more birdies! A no frills 40/20/17 m. radio with an upgraded software package and improved audio.
Whether due to proprietary fears or ability to document from a 3rd party, a schematic MUST at some point be included! Otherwise, I'm satisfied and as a friend allowed my to operate a new model 2 weeks before my purchase, consistent quality displayed in this latest run!
Enjoyed 20 meters from mid morning Sat. to 40 meters into a G5RV Sunday evening with a gel cell external.
Add documentation/schematics and it gets a 5! |
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| WB3D |
Rating: |
2015-09-15 | |
| Performs as expected |
Time Owned: 0 to 3 months. |
| I have found the TJ2B (2015 model) to serve my purpose as expected. I have used it with an end fed wire, a dipole and the whips that MFJ sells for use with the Yaesu 817 on 17, 20 and 40 meters. I am in Tampa Bay and have worked Georgia stations on 40 meters with just the whip without a counterpoise. On 17 and 20 meters I have worked normal skip distances QRP. Obviously performance is better using a counterpoise with the whips. Attaching a counterpoise to use with a whip antenna requires a simple workaround since there is no dedicated ground attachment point on the radio. The only required setup is to attach the internal battery and it helps to use a small Styrofoam shim for battery security. I travel quite a bit internationally and have run numerous test with a small switching power supply as well as external and internal batteries. I have used it with the Buddipole and find the results comparable to Kenwood and Yaesu transceivers at 5 watts (the output is a bit higher with the power supply and the external battery). The receiver works quite well. Audio reports for my SSB output have been complementary. I have not suffered the problems other reviewers mentioned with the unit I have. With the sporadic prorogation conditions now in existence I see nothing out of the ordinary in the performance capability of the TJ2B. For my specific low power purpose and considering the price it just fits the bill. |
|
| KI6GOT |
Rating: |
2015-08-06 | |
| DO NOT BUY: Awful radio, no support. |
Time Owned: 0 to 3 months. |
I bought this radio based on the QST review, which seemed to give the impression that the radio was a decent purchase. Boy was I wrong. This radio has a huge number of problems that make it terrible to use.
- There are hundreds of frequencies where internal oscillator noise (birdies?) exist on the amateur radio spectrum. I seem to hit a significant birdie every 5 to 10 Khz. Expect your over the air receive quality to be diminished or nonexistent every 5 to 10 Khz.
- There is a RFI type noise that seems to be coming from inside the radio which rolls around the receiver spectrum at regular intervals and completely wipes out a broad swath of receiver bandwidth. If you are in a QSO when this noise rolls onto your frequency, plan for the QSO to be over because you wont hear anything else... I have tried to isolate it by operating in different locations, different power supplies, different batteries, and with a dummy load attached. It's definitely inside the radio and maybe has something to do with a poor design in the power supply of the radio.
- There is an extremely loud pop made by the transceiver when you press and release the transmit button. This isn't much a problem when you use the internal speaker, but it will really hurt your ears and possibly do some hearing damage if you are wearing headphones. This is mentioned in the QST article, but I didn't realize just how severe this problem was until I used the radio.
- There is no grounding terminal on the radio. This radio really needs a grounding terminal for a counterpoise in order for portable operation to be effective.
- The smallest tuning step is 100 Hz. this is too coarse for anything that is off frequency, or narrow bandwidth modes such as CW or PSK. This radio really needs 10 Hz and 500 Hz tuning steps.
- The tuning step order needs to be reversed. This is mentioned in the QST article.
- There is no documentation included with the radio. You need to go to the web site and search around for it.
- There is no schematic. Don't expect to fix or modify your radio later.
- The battery is loose inside the case. I'm sure the Lithium Ion battery took quite a pounding on its trip from China, and I wouldn't trust it to be reliable or safe after an unsecured trip like that.
- The rotary encoder is flakey and doesn't work correctly if you turn it more than one step per second. If you turn it too fast then the frequency will flutter back and fourth around the frequency you started at.
- Youkits told me that they tested a radio they have and there are no problems. Rather than try to help me or replace the radio, they told me to read the QST article and send the radio back on my dime if I don't like it. For me, international shipping back to Youkits is going to cost over a hundred dollars... I have no idea what to do, keep a worthless radio that i paid $350 for or spend around $100 to ship it back and get some of my money back.
Learn from my mistake. If you want a working QRP radio, spend a little more and get a Yaesu FT-817ND or a Elecraft KX3.
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|
| REMOVED_ACCOUNT_43729069 |
Rating: |
2015-07-13 | |
| Very Pleased |
Time Owned: 0 to 3 months. |
I had the TJ-2B built to support transmission on 40m, 60m and 20m. Support for 60m transmit is not standard, but an email query resulted in a response that the radio could be built custom to support any three bands of your choosing with no additional cost and only an additional week delay in delivery. My desire was to have an NVIS capability on 40m and 60m for portable operation.
I used the TJ-2B with a Balanced Terminated Folded Dipole (90ft long) on Field Day, and made the first contact on the first call on 40m (Central Idaho to Santa Clara Valley, CA).
I also ran an SGC-2020, with DSP NR, and the TJ-2B was much quieter (wouldn't have required any DSP NR) on the same antenna at the same location. Very impressed with the receiver.
Measured output is 6-watts. Reported audio quality on transmit is reported by the receiving stations as being good.
When I first received the radio, I did some A/B comparison while switching the antenna between the FT-2000 and the TJ-2B. I am in an extremely low noise environment, and the TJ-2B, for what it is, and for my expectations, compared favorably in receiver sensitivity and perceived noise floor. It is surprisingly quiet! Receive audio quality with headphones (or iPod ear-buds) is excellent.
The only negative issues I found were:
1. The receiver will hear birdies on some frequencies.
2. The audio amplifier that drives the built-in speaker has very limited drive.
Aside from these two issues, my impressions thus far are very positive.
NOTE: I do not know if there is any SWR protection circuit in the TX. I have only used a broadband antenna that does not require a tuner. I also carry/use the FG01 antenna analyzer to make sure that the antenna match is acceptable before connecting the TJ-2B to the antenna.
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|
| CT1EHO |
Rating: |
2014-11-13 | |
| HF handheld DX!? |
Time Owned: 6 to 12 months. |
I love handheld radios since kid, my first radio was a 27MHz walkie-talkie toy, which after some modifications on someone tips and help of an old friend made possible to contact the CB guys around my neighborhood, I was hooked!
Sadly there is a big void in the HF SSB handheld field, I’m always wondering such is the actual state of the art in electronics why there isn’t palm sized evolved multi-band SSB radios? The fact there is already amazing SDR micro-chips for VHF/UHF FM handheld transceivers, I’m sure it wouldn’t be so difficult to implement the right FFT algorithms to modulate and demodulate SSB signals!
In the past the amateur QRP community had some more choices in terms of SSB HT’s, the great Japanese Mizuho company produced the amazing MX series, they were mono-band QRP HT’s that still sell nowadays on second hand market for high prices, and boy do they work well!!
Today in that simplicity and QRP spirit Youkits have produced an interesting rig, the TJ2B. Ever since I saw it on the web, I’ve planned to get one which I did!
The radio is very small compared with a full sized mobile transceiver, however if you hold it your hand for a while doing contacts with a telescopic antenna and the built in battery your arm will ache. The case is metallic black powder coated with a small green backlight dot display in the front panel, there are four buttons just right under the display, and two knobs on the top, one is the IF audio volume and the other a multi-function encoder, the antenna BNC connector is on the top beside the knobs.
The radio provides means to connect an external power source (DC 12v), a 3.5mm stereo jack for external speaker or headphones, and an external PTT microphone also a 3.5mm stereo plug, which is also located on the top panel
What I like on the radio:
-Size, the power consumption, the frequency tuning accuracy (DDS), and received audio.
Things I don’t like:
-TX power differences between bands, it produces a bit more than 5 Watts on the 60 and 40m bands, on 20m is around 5 Watts, but on 17m and 15m the needle stay between 2 to 4 Watts.
- Doubts about the durability of the multi-function encoder and the stereo jack connectors, note that I have opened the radio and saw these connectors are of good quality, but they are fragile on outdoor usage.
-I’ve noted there is a slight TX power drop if the radio is operated in hot environments, this could have to do with the design and the PA transistor configuration.
What can I say more about this little rig, well honestly it has been giving me some fun times operating on the main HF bands from hilltops and from my car with external mobile antennas, surprisingly the low power capability is not an handicap to make some interesting contacts, after all the propagation has been good, but most of all the fun part of it is when you say to your correspondent you’re transmitting with a handheld radio, the reactions are cool!
There are some extras that would enhance the TJ2B operation, two of them are an external hand microphone (I use a VHF handheld converted electret microphone), and a good earphone set.
I have other HF radios, the Yaesu FT-817 and a ILER-20 (home built), the TJ2B doesn’t disappoint the regular QRP operator, but it wouldn’t be a good choice for those who demand larger and more powerful radios. I’m a QRP operator and I can testify that its always possible to make good contacts and plenty of DX if one chose some proper techniques and radio etiquettes, RF power output is not so important on HF, a good receiver and a resonant efficient antenna would be enough for a nice couple of hours making DX… I even do lots of contacts with mobile whips on my car and from my apartment balcony using just my Youkits TJ2B! |
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| KF7YDL |
Rating: |
2013-12-15 | |
| nice for what it is |
Time Owned: 0 to 3 months. |
I was looking for a bare bones HF SSB QRP PSK31 suitable transceiver and the price here was much more attractive than the Yeasu 817.
Less features, to be sure, but OK for what I was after.
After taking it out of the box I set it up for PSK31 from the get go. Audio cables, cheap ($4) USB sound card and a breadboard fabricated microphone attenuator. 10 K resistor, by trial and error, in series on the mic line with a 1K in parallel across the mic ground.
Hooked it up to my 66 foot end fed wire, with a match box, and a vintage Kenwood antenna tuner.
The receiver is hot. Waterfalls from Korea and South Africa without tuning the antenna. Sent a CQ PSK31. Florida right off the bat. Contacts all over the US and Canada on 20 meters with 5 watts the first day. Big fun. Excellent signal reports. I'll be working DX soon.
I'm going to add a hand held PTT switch to replace the one on the radio. No CAT control here. Hit the macro and key the radio. Unkey when done. Works.
Cons, all minor:
No 10 meters
No S meter or transmit indication (my tuner has an S meter)
No battery charge indicator.
The display is very, very tiny, but it is backlit.
If you wanted to use this for phone, headphones or an amplified speaker are necessary. Very low audio output.
Together with an external microphone. The built in one is pitiful at best.
(Once I get tired of PSK31, and get the mic, I'll try SSB phone).
The internal battery and wall wart charger are sold as a "option". Mine came, extra $, in the factory sealed box. Buy them, they are necessary. Kinda a cheap marketing ploy though.
The radio comes without an antenna (makes sense, what would they supply, a 32 foot rubber duck?) and has a BNC male connector. This is not mentioned in the sales ad. Good thing that I had a BNC to coax adapter or I'd be spending a frustrating week waiting to hook up and use the radio.
Like I said, the cons are minor and nit picking.
I did four hours of TX RX two days in a row without running the battery down. For what its worth.
Nice radio. Great for PSK31. Might also be good for QRP SSB phone. We'll see
73 de W7WBB |
|
| WB8YQJ |
Rating: |
2013-06-27 | |
| YouKits HF SSB Kit Transceiver 14-30Mhz |
Time Owned: 0 to 3 months. |
I settled on a Youkits TJ2B after looking for a multiband HF QRP kit for under $275. The mainstream offerings in this price range are mostly missing 10 meters. I began searching for niche vendors to find something unique and fun, and came across Youkits in my internet search results.
The new TJ2B "Kit B" seemed ideal, offering 14Mhz to 30Mhz SSB +(CW Receive) in a handheld case and $269 plus ship.
Also offered is "Kit A" which is a 3Mhz to 14Mhz version.
The TJ2B is a great concept. It was a faster build but every bit as much fun to assemble as the K2's I built. The final product has a quality fit and finish styled like an Elecraft. The receiver is analog and has a great natural sound but you do need a battery or a well regulated PS, no wall warts.
It is a simple radio, minimal AGC on receive, 40 memories, and no computer interface but it is easy and enjoyable to operate even in the hamshack. It has fixed station quality received audio (using external amplified speakers) and low noise. It is extremely stable using a nice DDS with an LCD display. The case has a quality powder coat with bright white labels. The inside includes high quality PCB's with all pre-soldered SMT components. The firmware in the radio works well, it is flexible for setting up the BFO values and some other customization. The internal rechargable lithium battery is 1600mah and the radio draws 250ma on receive. The TJ2B is a terrific fixed station spotting radio, I leave mine on all the time operating from the station supply, antenna, and amplified speakers. RF output (using a pulser) on mine is 20m/1w, 17m/3.5w, 15m/4.5w, 12m/3w, 10m/2w.
This radio might not be for everyone however, for a number of significant reasons:
- Youkits is not setup to ship TJ2B in any kind of volume, they make very small batches and ship when they can, you will probably wait on your order.
- TJ2B is shipped directly from China.
- The assembly instructions work for savvy builders, they boil down to just some decent notes and photos. In one section of the assembly instructions you are directed to solder a section of coax directly to two boards that were layed out for MMCX connectors. Experienced builders will immediately see that some kind of a strain relief on the interboard coax connections is an absolute MUST. There are some assembly notes in the FILES area of the Yahoo Group for YouKits Canada. Magnification, strong lighting, and a steady hand are required to solder some tiny parts and to hand wind and tin small toroids.
- The kits inventory list is not comprehensive and the step by step assembly document is missing checkboxes. The photos you see when attaching a part does not always show the board that you are working on in the same stage of assembly as your own.
- As of today there is no schematic.
- The assembly for TJ2B is simple and the engineering and materials are amazing versus dollars paid. But if something is missing from your kit or the radio does not fire up at some test stage, there is no in-country support center staffed with parts, nor is there an in-country repair center if the unit comes to the point of last resort. There is one smart and very helpful man named Yimin who will do whatever he can for you within the constraints that he lives in Canada and most everything else is in China.
- If the radio does not operate within published specs even after proper assembly you may be asked to disassemble it, desolder and replace various components (normally resistors) in a trial and error fashion until it works as designed. Mainly in the PA section, said to be due to parts tolerances.
- Shipping radios back to China for service is either cost prohibitive (Fedex $175 from Ca.) or Customs prohibited (USPS). Servicing happens in China, not Canada.
- The quickly evolving HF line at Youkits seems to leave a higher than expected number of discontinued models.
Youkits is in it's infancy and their great desire is to innovate at a break neck pace. Their profit margins are slim to non-existent. You can get a terrific product from them and I really enjoy my TJ2B. The design is innovative and unique but it is a riskier proposition than going with with the more established brands. de wb8yqj... |
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