MX-P50M 45-Watt Amplifier - Big Boost or Chinese Junk?
Vložit
- čas přidán 12. 08. 2024
- I get a chance to try out the MX-P50M ham radio RF power amplifier in the field with my Icom IC-705. Join me as I get some real-world results putting this unit to the test.
Recommended to watch: Kevin Loughlin's "Ham Radio - Looking at the MX-P50M HF amplifier for QRP radios." video:
• Ham Radio - Looking at... - Věda a technologie
My first RIG was an 817ND, I still have it since 8 years. I was into QRP because when I was an SWL, the 817 was my dream because of its size and features. After I passed the HAM exam, I started to operate it as a base station rig with a dipole, and I found out that 5W is sometimes not enough for DX contacts. At that time was the solar minimum too, so I bought a 100W amplifier (modified CTE747 with LP filter). It made a huge difference. But on the field, I'm just using my 5W or with the 705, 10W. It's enough to make some contacts and even some DXs on digital modes. To me, the most fun is when I go to a random location, set up my RIG, and make contacts with the smallest setups.
@@pmate95 I find that 20W on CW seems to be the balance between signal strength, current draw, and equipment needed. 1 S point under a dollar, and an S point over a 5W box, which I can always turn down to.
12-15W is usually what I run if I’m running for an extended period.
Amazing comment, thank you!
I own several QRP radios with capabilities of 5 or 10 Watts. Rather than buying an amp for them, I take my FT 891 along and adjust the power setting to whatever works. One unit and watts selectable, no amp, no buffer, just my ldg tuner.
Thank you for describing your station!
Definitely like the real-world testing. Sounds like it works!
Sure does, Chris! Talk to you soon.
The restrictions are very similar to working with RM Italy amplifiers. Which I have incidentally found to be superb bargains.
Hello, thx for your video. 73 from north Italy, in the mountains in the alps
Thank you for sending your comment from a beautiful part of the world and 73 from VE3TWM!
My recommendation is the 'FT857 amplifier' from Yaesu. It provides up to 100 watts out and even has a built in SSB radio covering all the usual bands. No buffers or other accessories required 😄
Great video 👌
Your "suggestion" is completely valid! Thank you.
I also regret my 817 sale a few years back….but I’m now saving for 705….
Thanks for the video! I have an MX-P50 I sometimes use with my FT-817nd. I've had the same great results & no issues.... just for reference, I paid about $140 for mine.
If you think about it the 40w Amp is increasing a 5w signal by 1S point - so the difference in you report was being S7 in the noise at 5w to S8 - clear of his noise floor.
That the difference an Amp makes - pulls you above their noise floor
In my home QTH I work with a XPA125B with my G90. Both from Xiegu. It has 100W and a powerful tuner inside. I´m very happy with this combo. 73 from Austria OE3EBK
Thank you for sharing your experience! 73 from VE3TWM.
Good job here! Have one, used it a bit WITH the RFDAN buffer. I also have several others QRO amps, including Elecraft, RM Italy, and 60dbm. I installed a fan using bolts/nuts sliding inside the heat sink fins. My main use now for the amp is with 5W QMX on FT8. 73 de K4FMH
Thank you, Frank! I like the idea of adding a fan. 73 from VE3TWM.
Most transceivers (I say most) have a pull to ground PTT line so have an open collector that connects to the power amplifier which normally has the PTT connected via a load to the 12V line that the radio runs from. That load switches the PA to transmit. If the load is a relay then it should be damped by a flyback diode or similar. The FT-817 has no internal flyback diode across the collector-emitter junction of the PTT switching transistor so could lead to issues if the load in the PA is a relay and not protected. Check the schematics of the amp you have - If it's a POS then that diode won't be present and you will need to fit it yourself. The schematic of the M-P50M seems to have an LED in series with a resistor across the PTT input so should be OK.
Thank you!
Hi Tracy. I always like seeing a new video from you in my feed. 🙂
When I first got serious about QRP, I looked at this very amp. I concluded that for what I want to do, there's no place for it in the mix. I live in the Pacific NW where our big hazards are earthquakes and volcanoes. With my lifelong interest in EMCOMM, I finally figured out that Field Day is nearly a useless exercise for our situation here. Earthquakes come without warning, so renting a generator in advance to prepare for a disaster is not a thing. Everything must be battery powered if you plan to operate for more than a day or two. Fielding food, water, and shelter with no warning is hard enough so the station must be ultra-portable and required nothing but what what you can carry. And because we can have long periods in winter with very low sunlight, carrying solar panels for a quick recharge is not even an option. Since my TX-500 only uses 110ma on receive, I can operate for extended periods of time with just a modest battery. And unlike Field Day, my low power station won't be competing with all of the lids running KW class amplifiers.. We routinely practice QRP relays on our nets out this way so I plan for that capability when I'm running low power
Great points, Todd! Thank you for sharing the scenario.
Thanks for another video. 73
Thank you and 73 from VE3TWM!
I'm sure there's a difference with CW running 5 watts, which is the only mode I use when operating QRP. As for a 50 watt amp, I suggest getting one from QRP Labs.
Nice video trac. I use a ft-891 fer portable operation home made battery go box and two dipoles. A 40 meter and a linked for 20 17 and 15. Jim. Ps nice touch with the birds chirping in the background. Keep up good work. 73
Thank you for sharing what works for you! 73 from VE3TWM.
I Enjoy your work .73 !
Thank you! 73 from VE3TWM.
I’ve never used an amp but one that size seems like a nice fit for the 705
Hi Mike! They do work well together.
I wonder if one could install a series feed thru cap on the antenna hot to block any feedback voltage.
interesting tnks video 73
Thank you and 73 from VE3TWM.
Hmmm,
I have strictly Qrp radios with the Mchf clone called RS 918 being the newest.
I do have two small amps. The one from China I only tested once. I have been reluctant to use it because your antenna system needs to be presenting a standing wave of no more than the Swr reading of 1.5 indicates. The other amp is from Ukraine & I bought it primarily to support their war effort. Its a well reviewed amp, but it needs to see only 10 mW at input and although I bought a 30 db attenuator I have yet to wire it to power & give it a go. Of the two I would shoot for the Ukraine amplifier if I start talking, but I mostly listen now & then and do other things in the hobby primarily with antennas & radio astronomy.
As far as costs of the amps, each was around $100 usa.
Thank you for sharing your experience!
Did you measure the idle current when not transmitting?
Hi Philip, yes I did. My admittedly cheap voltmeter showed zero current draw, but the power LED was lit. No doubt the LED is some sort of magic device.
Oh my you've ticked off the die-hard QRP boys. They are some fussy ones (per these comments).
I appreciate what you've done here because I do (bragging a little) still have my 817, go box and all--but had considered running it mobile when I picked up a second vehicle--and that's when I'd put an amp on it. That's because mobile antennae are the compromise that they are on most HF bands, also that I'd need more wattage for any repeater outside the 5w range--okay-TWO amps.
BUT then I've never run an amp on my own station since being a ham. FAR from the days I spent running around with a "big" CB setup in my pickup. But I sold that amp along with all the CB gear and have been happy hamming since.
I don't see what the QRP guys are all beefed up about. Call your contacts like they are-when they are. Just because the rig is QRP type doesn't mean it MUST ALWAYS e run in QRP mode every day you communicate. Hamming is about communications and sometimes we'd rather make the contact than sit, lost in the noise, talking to ourselves. As much as I think QRP is fantastic, I'll have a "big" radio when I go portable (as well as QRP) because I don't have the sort of free time that allows me to pick and choose band conditions when I do such. As a few have stated here, it's a bit simpler to run a "normal power" radio than to add-on an amp (which you clearly showed us here) to a QRP rig. 73 from 4-land USA.
Great comment, Wade! Thank you for contributing to the discussion. 73 from VE3TWM.
You once said you were not going to acquire an IC-705. How ones mindset can change.
True. I made a video about changing my mind on the 705.
Hi Tracy,
well done to get this working and on the air.
However, seems like a cable mess which I definetly do not want to have on my table.
And risking a 1300,- trx to get damaged by that accessory? Sorry, but - no.
And rig, buffer, amp, tuner - with the three latter ones together at the price of a chinese G90, there is hardly no alternative.
25W, all-in-a-box, come on, Yaesu, Icom - time to wake up!
73 de Arne, DJ9AS
I agree with you, Arne! Better off with a higher wattage radio than the tangle of boxes and wires (and additional failure points). 73 from VE3TWM.
6:50 $100 for a "buffer box"?? I'd buy a cable and combine this with a tiny reed relay with integrated flyback diode like a DIP12-1A72-12D. Cost to to make yourself is
@salat: any chance you could send a schematic on how to build that?
@@TheTdub that would be too helpful. He just wants to scold.
For the love of god and all that is holy, please do NOT use an automatic tuner with an MX-P50M. I've popped over a half dozen transistors in my time foolishly using one. Maintaining a solid
Great advice, thank you!
Chinese junk. If the situation calls for more output power, bring a 100W radio along and adjust the output as necessary. QRP is not 45W, 20W or even 10W. It's 5W out. Thus, a 5W radio with a 45W PA is definitely NOT QRP. I've seen Tracy run true QRP with amazing results. Want the challenge presented by true QRP? Then run legitimate QRP!
doodoo
100W is Italian QRP
You will be a lot disappointed if you go to Walmart 90% of the products are Chinese junk