PreppComm DMX-40 - Morse Code Decoding QRP Ham Radio

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Physical Mail.............►Josh Nass P.O Box 5101 Cerritos, CA 90703-5101

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[HamRadioCrashCourse]

NOTE: RIT = Receiver Incremental Tuning! Sorry about that!

[NSSC]

3:07 really captures the excitement of ham radio, doesn’t it 🙃

[LubbockDawg]

Thanks Josh!! Very interesting!! Keep those quirky cards and letters and videos coming!

[echo-hotel]

They are shipping the new MMX soon. It’s a multi-band DMX basically. You can actually replace band cards, up to three per box. They only have 20m, 40, and 80m right now but they say they’ll be getting others made to be sold separately later on! I’ve been having so much fun with my DMX-40. Once I figured out external mode, which is easy when explained, I have mine semi-per-mentally set up to decode all the time while I use whatever key I want on my IC-705. I’m learning CW and if things get too crazy I have the DMX 40 to help get an idea of what I missed or who I can ask to go next in a pile up! PreppComm seem to only be able to make MMXs right now due to supply problems. Which isn’t bad as it should hear much better into the noise from what I’m being told! Have mine preordered. Might actually do some POTA and SOTA with the MMX soon.

[charleszimmermann]

I have lazy friends who won't learn Morse, and they have purchased these, and are happy with them, I will say the put out nice code when the operator actually knows how to type, but like many electronic devices "crap in equals crap out" I have an old Fox 3 Altoids 40 meter Wich the whole station fits in a small IFAK pouch that I carry with me when in the field, can only zero beat with but it works great. Got that idea from your channel 😉 thanks for the great videos.

[mattghoward]

There is now the MMX 80/40/20M version - Eric is also looking at upgrading to a cpu board that has wifi and bluetooth

[ProperLogicalDebate]

Morse Code isn't just for radio. Knowing it is also good with signal lamps.

[don_nskt]

Nice review Josh. I have seen some of devices like this that go into the phone jack of a radio and decode fairly well. Some club members bring them to field day to allow others to read over their shoulders. I just don't remember what they were and if I recall, they are 10 to 15 years old.

[izmazix]

You know when you've been thinking of a problem for months and can't find a solution? You think "surely someone has solved this?!" Then you stumble upon it; that is this moment. I'd love to see a more in-deapth stream or video using this by itself, because the downsides mentioned were because it was connected to another radio.

[samradioman]

Thank you for correcting the info on what R.I.T. is or isn't. I'm an old school extra CW Op first licensed in 1975 as a novice. As mentioned in a previous comment R.I.T. stands for Receiver Incremental Tuning. It's use was so that you could tune your VFO to be dead on center frequency a.k.a. "zero beat". At zero beat all you will hear is thumbing as there is no audible offset to be heard. You then use the R.I.T. function to adjust the RX only to be an audible tone to your preference without changing your TX VFO frequency. Some like a 600Hz tone, others might prefer 700Hz or 800 Hz. It allows you to adjust your receiver independently of your main VFO that sets your transmit frequency. That leaves your TX dead on center frequency.

It seems these days the understanding of how zero beat works and what it means is a lost art. I often hear CW Ops off center frequency because they are tuning their TX & RX with just the single or main VFO. Why that is important is a discussion for another time HI HI. 73

[Jody_VESAR]

The Icom 705 Mk. II should be able to absorb all of this functionality, and ship with a more universal USB keyboard interface. :-)

[niyr]

I've run across this product and found your video informative if not timely. Just a quick note for those of us who are getting older and have lose a lot of our hearing I think this product will keep us in the hubby longer. Just as the voice to text software has helped. Just a side benefit. I to wish this was more plug and play into some of my current radios. Thanks again and keep up the great utubes. 73 N2IYR

[BosssyBear]

Looks pretty cool but should have had a BNC instead of the SMA. SMA is designed to be torqued and you can only do that so many times. Finger tight will get more cycles out of it but it's still more fragile.

[kxg]

The reason this hears so well in the noise is that the decode audio freq is 1300, not the 600 or 700 Hams have been using by ear. I have one, it works great external. If you zero beat yes you must RIT to get the audio to 1300hz. I use mine external for decode only and use my Fldigi and Mini Winkey Usb to TX off my Raspberry pie. I liked your demo of DMX to DMX via the QRP radio.

[janiceemery]

Josh, what is that little red straight key that you show in this video. I like that and its size.

[Blue-Collar-Radio]

I was going to offer to send you mine after I had a chance to get used to it. The 2 things I don't like about it is it doesn't support an Iambic key. And it doesn't seem to support a Bluetooth keyboard (with a dongle). I think this radio could have been much better than what it is, if at the very least it did those 2 things. Also, I feel like it just feels really cheap, it could have been in a better case at that price point IMO.

[thugpug]

I'm not sure if you're worried about views at all but long premiere times tend to destroy the initial viewercount. I'll definitely watch this one since it seems interesting but from what I've seen other YouTubers say, 45 minutes is really the max you'd want to set a premiere at.

[BrandonGlenn]

I am looking for a way to communicate from Connecticut to Tx in an emergency assuming there is no internet or phone. Do you think this device on the 40m band would be able to do this?

[candomommy]

I really think you should make a video on the uSDX uSDR HF radio. If it was ok as a QRP rig it could bring in more people to HF radio cheaper. -K0NNK

[ChrisNPEM]

Curious Josh if you have an opinion as to how this compares with the decode in the KX2?