| KD0ZW |
Rating:  |
2013-08-11 | |
| BITX20A is an Awesome Xcvr on 20M |
Time Owned: more than 12 months. |
Hello QRP builders...
The BitX20A is an awesome kit. I built mine in 2008 and added the FCC-1/FCC-2 for digital readout. Love it... Been running it with Solar Panels since 2008. You need to take your time building this radio. I used an old M435 Mil grade osc. to fine tune mine when it was completed. I did blow a could of power FETs and screwed up some parts placement... but hey it happens. Since I got'r dun in 2008, I have not touched any adjustments for years. Using an old Turner 2+2 mic., I do replace the 9v battery now and again. Hams all over the globe tell me it sounds great. And for ~6-10 watts PEP they can't believe it. Antenna is 28ga wire resonate 20M dipole on my deck railing, (no tuner or balun), and up about 12ft. Nut'n special. Best SSB usually > 5000 miles. It's been on Cub scout camp outs for kids day, used on every field day since 2008 and it keeps up with my old reliable Icom 751-A.
View it here: http://kd0zw.com
I used a plastic case and added a small fan on the back. Mine covers 14.050 to 14.206. I feel Hendricks and all of the legendary builders that helped make this kit happen should be applauded. It's sensitive, selective, and efficient. It's well done and I would not hesitate to buy another one! If I wasn't such a slacker, I would have the PSK as well as the CW working on this rig... I'll get'r'dun sooner or later...lololol
Need to hear it with your own ears? Drop me a line OM for a sked on 20 Mtrs... monam1@mchsi.com
Well done Hendricks!
http://kd0zw.com
72,73
Mike
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| KB9GKC |
Rating: |
2013-06-18 | |
| Excellent radio |
Time Owned: more than 12 months. |
Hello,
The Bitx20 transceiver has a very nice sound that you can listen to for hours.
I built mine in about a week during my spare time and it worked the first time I turned it on. The digital display was a nice kit but I had a device slightly off the pad. Repaired and display worked well. Check out my Youtube video of the BitX20.
http://www.youtube.com/watch?v=TbNZgjStAVI
73
Douglas |
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| K4DSB |
Rating: |
2013-06-17 | |
| Excellent Radio see QST May 2013 review!! |
Time Owned: 6 to 12 months. |
I have to post this, as its very helpful to all prospective buyer/builders. In May (2013) QST, the ARRL Lab built and reviewed the Bitx17 (same radio really as the Bitx20A only frequency changes). They gave high marks to this very nice 17/20 Meter SSB QRP radio. Please read the article if you plan to buy and built a Hendricks Bitx17/20 SSB transceiver. As an owner of one, it is important to follow the instructions carefully and get help from the Yahoo support group if needed.. YOU will be rewarded with an outstanding high performance radio. All bad reviews so far are from wiring errors, part placement errors or alignment issues. This is a proven circuit built by many hams... K4DSB
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Earlier 5-star review posted by K4DSB on 2011-06-13
After finishing my Bitx20A (from Hendricks Kits) and performing a few modifications to enhance this great kit.. I can only say how rewarding, fun and educational the BITX20A has been. First, it has a quiet and sensitive receiver (measured in my lab readable signals as low as .6uv) and fair audio on the internal speaker. (recommend an external for great sound). Second, The transmitter is very clean, can easily (at least on mine)peak 12 to 15 watts PEP. You also get super support from the Yahoo Bitx groups, with tons of drawings, helps, photo's and one on one blogs. I added the frequency display (ordered with kit) case and mods of: varactor (electronic tuning) ext spkr jack, cooling fan, mic gain control, S-Meter and AGC... it now seriously kicks... Aligned with good lab equipment (not necessary but helpful) and I'm using a Samson Q6 microphone.. audio reports are excellent.. many may consider the Bitx20A just above the QRP range but the extra power is welcome! (uses a pair of IRF510 JFETs) PS..........YOU won't be disappointed... |
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| KD2AJO |
Rating: |
2013-06-12 | |
| Needs serious revision |
Time Owned: more than 12 months. |
| I first bought this kit a year ago thinking it would be a great little backpacking rig I could use over that summer. I was wrong because it has not been until this morning that the thing could actually receive anything. The manual has way too many mistakes, and is way too hard to follow. A first time builder should not try this. The kit came with all the parts, but it was disappointing that he doesn't include the polyvaricon shaft. The PCB layout is pretty bad, and all the resistors are vertical standing, even where they could be flat. The problem with mine was that the VCO never worked. It took me a while to figure this out, because when I first built it I didn't have a scope, something you MUST have even though the manual states otherwise.The only reason it works at all now is because I rebuilt the VFO on perf board. I think the circuit has been changed too much, and he should have just left it as the original circuit. If he was going to make so many changes, there are certainly alot of things that could also be fixed. For example using a real voltage regulator in the VFO, and also ditching the IRF510s for something made to do RF. If you really want to build a bitx, go for the v3 kit, it may be hard to find but I think it is still out there. If you are just looking for any old SSB radio kit, go for the ILER 20. I built the 40 meter version and it was very easy to assemble and took very little effort to actually make it work. |
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| AC2JB |
Rating: |
2012-12-22 | |
| BITX20 version, thumbs down |
Time Owned: 3 to 6 months. |
A fellow ham and I each independantly assembled bitx20 kits. Neither worked. (In both units the receivers were unusable, weak, with whistles) This kit is NOT for those who wish for a refined kit ready to assemble without significant issues. Not for most beginners.
Documentation was poor and incomplete in the most crucial areas such as transformer winding and connections. Parts were missing from both kits. Some parts were mis-labled or inadaquately described. Special instruments such as signal generator or an existing precise receiver are necessary when assembling these kits.
Both kits had inadaquate, very poor receive performance.
I beleive the bitx20 design itelf requires substantial improvement. A main tuning capactior is used and the circuit is subject to instability. Transformers should be premade.
Response to queries from Hendricks has been slow. (meaning if you have trouble, you can go ask the forums ...good luck with that!)
What to buy then?
I'd go for a Small Wonder Labs kit, I've built seven of these kits with no issues at all.
Unfortunately, the selection of SWL models is now very limited.
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| N0NZG |
Rating: |
2012-12-10 | |
| Great radio , poor manual and oem support |
Time Owned: 0 to 3 months. |
I am one of the few people that has had a bad experience to report about the bitx 20a kit from Hendrix QRP kits. First of all this is NOT a kit for beginners at building kits. You will need an in depth knowledge of how ssb receivers and transmitters work to go from a box of parts to a working radio.
The documentation with the Bitx20a kit is awful, to say the least. The docs for the 17a kit fill a fair amount of the gaps, but not all. You will need both manuals to build a working radio. You would think as easy as it is to cut and paste a manual together it would be pretty easy to spend 2 hours and turn out a comprehensive manual for the 20a
The parts like zener diodes and a few others that were shipped with the kit are NOT the ones called out for in the build sheet so the builder is left to look up the actual parts that were supplied and figure out which ones go were.
The wire sizes provided are not the same as called out for in the build sheet to wind the inductors. The wire provided works just fine but is all the same size ( as measured with a micrometer ) and leads to confusion on the part of the builder to figure the inductors, as the VFO inductor calls for a different size wire from the rest. There is no photo or drawing to tell you what the orientation of the 6 wires exiting the trifiller wound transformers should be. You will need the 17a manual for that.
The manual is full of wrong and contradictory component values and descriptions that unless you are very careful NOT to follow the manual there is no way you will end up with a working radio. Thankfully these issues are so well know that there are a lot of resources on the Internet to act as an addendum to the manual. The main components that have issues are R21 , C79, R60, R59, D8, C15, and D9
You will need to download the manual for the 20a ,17a , digital dial, and case assembly.
The tune up and alignment section of the manual is so poor that it's a miracle that anyone that is less than an RF engineer ever used it to get the 20a working. You will need 17a the manual for this one.
I spoke with Doug Hendrix about parts I was missing from my kit and now 3 weeks later I have had one email from him ,but no parts and no follow up to my 2nd email when I also found out that I was missing the speaker mounting hardware. The Bill of materials for this kit is so incomplete there is no way anyone could inventory the kit to see if they were missing parts until you need them.
On the flip side there are extra parts included in the kit with no instructions what to do with them leaving the builder to search for what he forgot to install. Turns out some of them are to add a mod to the final amp to make it stable under ALL swr conditions. Others you won't actually use. Again you will need the 17a manual for this one.
The use of a cheap polyvaricon cap makes this kit a pain to tune and have any fun with. Considering the price of this kit currently of $180.00 and the fact that the parts to use a varactor diode and a ten turn pot for tuneing would add less than $15 to the cost of the kit why not include it in there and move this kit a little closer to the great little rig it could be. NO, I am not going to gripe about no AGC, the radio is a pleasure to use even without AGC
The digital dial requires soldering surface mount parts and is very easy to build. The manual for this part of the kit is exceptional and the counter works like a champ except for the multiplexing noise of the LED's in the receiver audio. There are instructions in the manual for the builder to buy more parts to add on to try to get rid of the noise, but that doesn't work anyway, so don't bother.
At the end of the day I have a working radio that is a ton of fun. Along the way I used a lot of Internet resources and time spend chasing the quarks of the poor manual. I never did get my missing parts , however I did get a great education on a lot of different fronts. I added the 10 turn tunning mod and the mod to make the finals stable. This is a fun rig to make if you want a foundation to modify and make your own creation ,but if you want a great rig out of the box, I wasn't so happy. I have made plenty of contacts and the RX is as good as my TS570D or TS480. I get 12 watts PEP output and great TX audio reports. IF you know and except the limitations of what you are buying then you will have a lot of fun with it. I wish QRP kits would make a larger case with room for more mods as an option. OK, ya and AGC.
I encourage anyone building this radio to go to
http://www.golddredgervideo.com/kc0wox/index.htm
and watch his great videos. Without Leonard's great help, I would still be trying to get my rig working.
How would I fix the short comings of this kit to make a better user experience?
I would merge the relevant parts of 17a manual with the 20a manual.
I would fix all the typo's and technical errors.
MORE photo's or drawings
Better support and attention to detail in packing the kits.
With permission of course, include a LOT of the t-shooting and scope shots that KC0WOX has tirelessly put together to help everyone that builds these rigs.
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| VA7ION |
Rating: |
2010-10-14 | |
| very quiet receiver |
Time Owned: 0 to 3 months. |
Have the 20m version. Very quiet receiver, nice audio, and the 10W is plenty to work any station from American continent coast to coast, Hawaii, and Japan even on this poor propagation condition. I use it portable with an end-fed antenna. Love to work those big guns running full legal power :)
Just ordered the 17m version, too bad is offered only at $180 as a complete kit. |
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| 5R8GQ |
Rating: |
2009-05-10 | |
| Very Nice Radio |
Time Owned: 3 to 6 months. |
This is a great kit and went together very well.
Receiver performance is very, very good, despite lack of AGC. (Why couldn't they have added that on there?)They now offer an enclosure kit for the outrageous orice of $50. I am glad I got the board only kit! I use a modified COBRA CB Mic with mine andam getting 10-12 watts out on peaks.
I ALMOST gave it a 4 because it doesn't have any AGC, which is really, really annoying when tuning across the bands. If you are using headphones you can get blasted out of your chair.
All the parts, PC Boards, and manual are very hugh quaility. Plated through hole PC board. I am not going to get the digital frequency dial for it. I have it setup in the SSB portion of the band, what else do I really need to know?
Tuning with the main dial, a one turn Polyvaricon Cap, can be tricky, but works easier if you use a large diameter knob. I am going to replace this with a vernier reductoins drive. There IS a "fine tuning" control but it is of limited range. If you accidently bump the main dial, you'll have to retuned the main knob again anyway. It is also a great value at the $85 I paid for the board only kit. Too bad Steve no longer offers the MMR40 as a board only kit. |
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| ST2NH |
Rating: |
2008-03-27 | |
| great project |
Time Owned: 0 to 3 months. |
this project is great
tnx Ashar Farhan
the kit from qrpkits is great too
tnx n7ve
the bitx group is so helpfull it's a complete
QRP school on the net
tnx yahoo bitx's group
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| JL1KRA |
Rating: |
2008-03-19 | |
| Great design to keep us remind real amateur radio |
Time Owned: 0 to 3 months. |
Spending several weekend spare time, finally I completed my BTX20A after 2 months.
Though I have experience of several QRP kits, it was formidable one including many toroids to be wound and many discrete parts. But I was encouraged by other builders report and work in Yahoo Group.
Sice the Group is already subscribed by more than one thousand, it must be very careful to post messages. Basically individual problems what you face is already happened and you can see in past messages. Find them first. In addition ,the Group is not only for 'BTX20A'. They discuss other BTX20 flavor as scratch build, FAR Circuit board and recent Ver.3 board from India.
Mention about the BTX20A kit, an original assembly manual in qrpkits.com is well written step by step instruction. In this manual, parts mountings are separated into small section and minimize your human error.
Adjustment is clearly seen in videos now. PA djust video and basic alignment video by KC0WOX are my first video experience learning how to adjust rig from forerunners. Image training with the video avoid blow IRF-510 MOSFETs by over current. DVM which can read mA level current in 5-6A range is the must have equipment to adjust driver and finals.
As for BITX20A kit itself, though there are a few hundred parts, it is amazingly perfect since there was no missing parts and no extra parts. Doug's qrpkits.com is doing excellent work.
But once you bought the kit, all responsibility toward completion is in yourself. In any case you should not claim to qrplits.com as you do to Yae-com-wood.
Sounds of BTX20A is exceptional. With minimum number of active device fully working, tuned only 20m band, readability of receiving voice is better than any other recent commercial rig. If you know TS-520's good sound, I feel BTX20 is similar to this old good Kenwood.
Adjustment in TX is rather critical. Driving MOS-FETs less than 10W is good choice to suppress spurious and using final safety.
Overall, started from Ashhar's design, the bitx20 is the most educational QRP-SSB kit for me. I was learned a lot from this. I hope many 2-ways BTX QSO in this solar cycle.
JL1KRA/AA3ZT
Junichi Nakajima |
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