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Reviews For: BX-184 kit

Category: Voice Keyers

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Review Summary For : BX-184 kit
Reviews: 16MSRP: $59
A Voice Keyer kit that fits inside a Yaesu MH-31 mic case.
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
G1YBB Rating: 2016-04-23
Super kit and very innovative Time Owned: 3 to 6 months.
I bought this kit literally minutes after I knew it existed. It is the perfect design, extra functionality without extra equipment.
I used to have an external CQ parrot that I built but that was in a housing bigger than the Kenwood 751E it was attached to and needed power and cables. Building into the microphone is just perfect.

The kit came quickly and was fully comprehensive. I went for the option that comes with a copy microphone so I did not need to butcher my standard mic. I expected an empty shell, but it was actually a complete working mic.

The PCB is part surface mount (that bit is done for you) and part through hole components (you fit those)
Inspecting the board I can see the surface mounted parts have been done professionally on an SMT line (I design PCBs in my day job and they build them downstairs).

Anyway, basically I followed the instructions to fit the parts and it worked.

It worked very well.
I even saved some weight which as a backpacking SOTA and contester is great.

I put the full build experience here:

When I bought it you could only buy from the German site (thanks Google translate!) but now I see there is a US distributor where you can get them. (I have it on my link provided)
AA2LF Rating: 2015-05-14
best keyer for the money Time Owned: 0 to 3 months.
The last contest I entered (RDX) showed me the need of a voice keyer. Looking on the market I found few products with bells and wistles, memories and a lot of space requirement in a shack. Then I found the BX-184 and I relized this is the only voice keyer one may need!
For the following reasons I gave the best mark:
- The message memory is enough for CQ de .....contest.
- No shack real estate needed, fits inside the original microphone for Yaesu or Icom rigs
- No additional power required
- No need for adjustments
- Very simple assembly, suitable for all levels of skills
- Shipping from Germany takes 5 days (to NY metro area) and can be tracked
- Price is about half price of the cheapest on US market
- Tech support answers any mail same day
- Can be used in contests or DX chassing
Also, I was told the audio is better with this new electret mike but that may be subjective!
All those being said, what other mark I can give?
I think 5 is the real rating and I hope all other reviewrs are with me. (I did not read them yet!)
Good job FubkAmateur team!
EA5IGC Rating: 2014-11-01
I won't call CQ without it Time Owned: more than 12 months.
I built this kit in a couple of hours just after I bought my first HF radio, a FT-817ND. I worked for about a month before without it and nearly lost my voice on several occasions. This gadget is now completely indispensable. I also get very favourable comments on my audio quality and modulation so the little electret insert must be pretty good. I attached my mic insert with Blu-Tack rather than hot glue so that I could change back to the standard Yaesu MH-31 in just a few minutes. This week I got my first 100W radio, a FT-450D and I'm hoping it will work with that too. It's certainly promising since both the FT-450D and FT-817ND are shipped with the same MH031 microphone.

One might ask why you'd need this with a 450D since that radio does include a built-in voice playback function. Well, yes it does. 10 seconds and you need to keep pressing the playback button. With the BX-184 you get up to 60 seconds of message which it will play back (with a configurable listen pause) indefinitely until you click the PTT to stop it.
VE7VTC Rating: 2014-02-24
Quality kit Time Owned: 0 to 3 months.
This kit has excellent quality parts and works well on the FT-817ND. I ordered the kit with the mic enclosure (to keep my stock mic intact) and it all went together without a problem. The instructions are generally good when combined with the pictures. Look at the pictures carefully as there are good construction hints that are not in the instructions (such as covering the weight screws with hot glue to prevent loosening and to insulate them). They could provide info about setting RP1 audio level but that is nit-picking. Also the builder is left to to cover the 1-2 switch hole in the back of the mic enclosure. I used electrical tape on the inside shell filled with hot glue from the outside. Overall I am very pleased with the quick shipping, price, product quality and good audio reports on the air.
FP5CJ Rating: 2014-02-18
good also with FT 817ND plus AMP Time Owned: 0 to 3 months.
I forgot to say that it is working very fine too,with a 200W HF mobile AMP behind he FT817ND.
Modulation is very good.
It is then a very usefull D-V-R gadget to get through pile up's OTA,and without getting tired announcing our callsign OTA on and on...
DG2IAQ Rating: 2014-01-09
Just perfect ! With 5++ Time Owned: more than 12 months.
Just an update to my posting of May 2011.

In the meanwhile I own 4x BX-184. As I'm always a critical audio listener and as I hardly can be satisfied, this means this product cannot be that bad, I guess ... :-)

2x for my both Yaesu FT-817ND portable
1x for my Yaesu FT-847 at home
1x for my Icom IC-7200 home/portable

One major thing I always changed on all four kits.

I do always replace C8 (4,7µF) by a nonpolarised SMD 1,0µF to fasten up the AGC. With this Change the internal AGC works more as a mic compressor than as a (slightly delayed) mic Level limiter.

Especially great results on the FT-817ND which has no internal speech compressor or speech processor by its design. And the additional "voice keyer" is a big plus for getting real "relaxed" CQ calls with the (poor) QRP power. This makes life much easier, hihi.

Yesterday I received the last one (for my IC-7200). And for the first time I changed R4 (82k) into 56k to bring the sample rate from 8kHz up to 12kHz (by a shortened play time of 40s instead of 60s, but that's still more than enough for my needs). This change gives even more punch for the replayed calls as the sound is a little more high-pitched afterwards. You simply can solder a 100k SMD in parallel to R4 instead of completely replacing it.
But I fully agree with the other collegues here: Even in stock design (= 8kHz sampling rate) people usually won't hear any difference in between the human voice and the recorded one.

My conclusion:
Absolutely top product with a good RF resistance (no doubts to be used with a FT-817) and a good sound. And with an optionally slight fast compression by changing one electrolyt capacitor.

vy 73,
Jochen, DG2IAQ

Earlier 5-star review posted by DG2IAQ on 2011-05-30

Just finished soldering yesterday and did some brief tests on the open case yet.

Everything works fine and sound is great as well. No remarkable difference in audio quality in between the original voice and the recording.

But one thing was never mentioned yet in any publications and you only can find it out by having a closer look to the datasheet of the ISD1760 and the BX-184 schematic:

As the ISD1760 routes the mic audio line all the time, even in non-repeating standby-mode, its AGC works for the normal audio as well !
This is a great side effect as the FT-817/857/897 do not have any internal mic compressor. And their MIC line level setting works AFTER the internal mic amp and cannot prevent distortions on the 1st stage.

I will try to fasten up the AGC time by lowering C8 (4.7µF) as I like fast AGC much more. Let's see if it will work here as well.

But with a proper aligned total audio level, the BX-184 MH-31 is perfect for great audio.

...even if it surely was NOT the origin intention of the designer...hihi.

vy 73,

VK3XPT Rating: 2013-09-04
Excellent results! Time Owned: more than 12 months.
I purchased the BX-184 kit over 12 months ago (with the help of Google Translate), and I am glad I did.

I have tried a number of different microphones with my FT-817ND and without doubt, the BX-184 audio has proven the best. I have done side by side microphone tests with DX stations, without fail the BX-184 is a clear winner. It drives the FT-817 harder than the standard Yaesu mics with more clarity, and it appears it provide a small and welcomed amount of compression.

And lets not forget the voice keyer - it works great and recorded audio is transmitted with perfect quality - receiving stations can not tell the difference between a recorded call, and a "live" call. Working QRP and calling CQ, or trying to break through a pile-up is no longer a tiring process. The BX-184 takes care of that!

The only point worth mentioning is that the FAST (FST) feature is not accessible on an FT817 when using this microphone, as the FST button is used to control the recording and playback functions. You can use your standard mic to select Fast or Normal tune modes, and the rig will remember your setting. (I always use Fast mode and this has never caused me a problem).

Despite the lack of FST functionality when used with the FT-817, the BX-184 is worthy of a 5/5 rating.
K2JB Rating: 2013-06-27
Excellent Kit Time Owned: 3 to 6 months.
I looked all over for a voice keyer for my IC-706MKIIG and this was exactly what I needed. I was able to assemble it quickly without any issues. I saved my voice in the last contest. Olli, DH8BQA was very helpful in assisting me with the transaction. He has made an excellent kit and I recommend it to anyone looking for a voice keyer mic.

Dean ~ k2jb
S58J Rating: 2013-03-17
Must have Time Owned: 0 to 3 months.
It is simple and highly functional and as a bonus it makes your modulation better (even when not in repeating message mode).

I use it with my FT-817ND and this addition makes this beautiful little rig even better.

If you compare it to other DVK modules for bigger rigs it is cheap as well.

I highly recommend it!!!
DL4EAX Rating: 2012-06-19
Just great! Time Owned: 0 to 3 months.
This kit is easy to build, since the SMD components are already pre-assembled. Replacing the interior of original MH-31 with the board provided by the kit works fine, all fits 100% OK. The only thing that needs a bit patience is hot gluing the new electret capsule into the original MH-31. Just take your time and it will work.

Once you have finished the kit, you will have a MH-31 microphone that can call CQ for you. Very handy for SOTA and WFF expedition, because you have to take a microphone with you anyway.

Operating is easy and intuitive.

I use the BX-184 with a FT-847 and an Elecraft K2 (where the microphone is wired like the FT-847). Good audio reports and a bit of extra punch compared to the original MH-31.

For contesting and when working from home there may be other solutions like playing audio from the PC, but for portable (QRP) operation where no computer is around, the BX-184 is really what I have been looking for.