@@hamradiotube hello Mike, driving out Grand rapids this weekend to pickup my Heathkit Sb-201 600 Watt HF amp. Silent key estate stuff. Let's get together next weekend. Thx a bunch 👍
Would have been nice if you would have checked the transmitter then turned on the amp incase the amp was just amplifying something bad from a rig. I am really thinking of buying one of these. Amp and Tuner in one I am intrested.
Is the "trash" from the radio or the amp? See a linear amplifier will amplify the input signal so you have to check what's driving it, the x90 against the output for a real picture..
Thanks for showing this. What was the test which you were doing? 2-tone TX test? Or just plain carrier? I wonder whether what you were seeing was spurious emissions, perhaps from the driving radio? Perhaps measuring close-in 3rd-order IPs, from a 2-tone test, would be a good test of linearity.... if the spectrum analyser goes that fine on resolution.... (Not sure whether the SA was overdriven during the test on 1.8 MHz?). 73! Tim
Most likely it was overdriven on 160 m test. I have one and find that on some bands you only need to put about 1 watt in to achieve maximum output. I also second your comment about using a two-tone test. That would be much more precise than a dead carrier on AM mode. Also if you're running a quality radio that has Pure Signal (pre-distortion) you can most likely clear up any issues on the second and third order.
I'm gonna trust the guy who has worked in the RF industry his whole life over a random person commenting (with spelling errors I might add) without any context to his claims, but I do thank you for watching.
Very interesting test. I mostly work portable on 20 and 40 meters so this amp would work for me. But, since it's questionable on 17 meters and really poor on the low bands, no way would I purchase this amp. I'd like to see if it has power spikes when operating CW. Thanks for posting this most informative video. Barry, KU3X
Question: Practically speaking, what does the extra noise on those bands translate to when operating? I mean, presumably you’ll get more range with more power, but does it mean you interfere with neighboring operator’s signal on other frequencies?
The noise are spurious emission spikes. That means the amp isn't putting out a very clean signal and could interfere with adjacent stations. You could also be causing interference on the harmonics of those frequencies. For example 15 meters is a harmonic of 40 meters, so you could be splattering all over 15 meters and not even know it. Most of the bands tested with this amplifier were within FCC regulations as they were below the allowed threshold, and likely to not cause interference.
Yeah, well that is not as clean as one would like, but as you say it is certified. At the end of the day, now you know where it is dirty would you use it there?
@@hamradiotube The transceiver connected to XPA125B looks like X5105. G90 has different form factor, smaller display, and the display is color OLED or backlit color TFT, while the transceiver in the picture has clearly an "old style" B/W LCD with gray background and its dimensions are greater than G90 display. I own a G90 and it definitely does not look like the rig you have in the video... What we did not see is how's the spectral purity of X5105 itself. Without that, you cannot say for sure that, for instance, the spurious IM products on 21 MHz are from X5105 or from XPA125B. It could be an interesting video but in fact there are too many unknown variables to make definite conclusions.
@@ok4rm Oh yes, that. That is what you call a slip of the tongue. But thanks for pointing it out. I'm very aware of the differences between the 2 radios as I own both. In fact, I have one of the more popular review videos on RUclips about the G90.
Killer video! Makes me want to check out my amps to see how clean they may or may not be.
Thanks Craig. It's nice to see what your equipment is doing for sure.
Hello, I got my popcorn ready. Nice efforts and discovery the Pro's. Thx a bunch N8NSK
Hope you enjoyed the show. Thanks for watching.
@@hamradiotube hello Mike, driving out Grand rapids this weekend to pickup my Heathkit Sb-201 600 Watt HF amp. Silent key estate stuff. Let's get together next weekend. Thx a bunch 👍
@@shawjw247 Thats awesome. Next Sunday might work.
Nice job- Thank you for explaining the differences of clean VS dirty
Thanks Don, I did it for you lol!
K8MRD RADIO STUFF .... because you know my next purchase is going to be an amplifier (wink)
Yep, as a noob vids like this really help!
I’m confused - how do we know that the problems on 80 and 160 are coming from the amp, rather than the signal source in the radio ?
I guess we don't now that you pointed this out.
If i remember the drive at 160m needs to be less than 3 watts mabe 1.5w you were over driving it at 5watts
Very nice detailed analysis. That’s a good friend to have!
Yeah I lucked out for sure.
Please test those same frequencies directly on the Xiegu X5150
I have tested the g90 and x5105 and they are good.
On the low bands where high harmonic emission was seen, did you check the G90 by itself?
Would have been nice if you would have checked the transmitter then turned on the amp incase the amp was just amplifying something bad from a rig. I am really thinking of buying one of these. Amp and Tuner in one I am intrested.
Interesting, I would get in contact with MFJ and see what they have to say about your findings.
I don't think they can get much info from Xiegu. I've asked how to do a factory reset on this radio and they couldn't tell me.
K8MRD RADIO STUFF Wow!!!!
@@BadHorsie2 Yeah. Seems like it would be something easy to do but there is no documentation anywhere.
Why was AM used?
Curious if this amp doesnt like AM?
Is the "trash" from the radio or the amp? See a linear amplifier will amplify the input signal so you have to check what's driving it, the x90 against the output for a real picture..
the amp. I've tested the radio.
Thanks for showing this. What was the test which you were doing? 2-tone TX test? Or just plain carrier? I wonder whether what you were seeing was spurious emissions, perhaps from the driving radio? Perhaps measuring close-in 3rd-order IPs, from a 2-tone test, would be a good test of linearity.... if the spectrum analyser goes that fine on resolution.... (Not sure whether the SA was overdriven during the test on 1.8 MHz?). 73! Tim
Most likely it was overdriven on 160 m test.
I have one and find that on some bands you only need to put about 1 watt in to achieve maximum output. I also second your comment about using a two-tone test. That would be much more precise than a dead carrier on AM mode.
Also if you're running a quality radio that has Pure Signal (pre-distortion) you can most likely clear up any issues on the second and third order.
Nice job Mike 👍
Thanks buddy.
1st: the analyzer is overloaded
2nd: garbage in-garbage out > did you measured spurrious from exciter first?!
I'm gonna trust the guy who has worked in the RF industry his whole life over a random person commenting (with spelling errors I might add) without any context to his claims, but I do thank you for watching.
Thanks for doing this because seeing is believing.
My pleasure!
Very interesting test. I mostly work portable on 20 and 40 meters so this amp would work for me. But, since it's questionable on 17 meters and really poor on the low bands, no way would I purchase this amp. I'd like to see if it has power spikes when operating CW.
Thanks for posting this most informative video.
Barry, KU3X
So … what can we do filter wise to clean up the output on 160 and 80 ?
Question: Practically speaking, what does the extra noise on those bands translate to when operating? I mean, presumably you’ll get more range with more power, but does it mean you interfere with neighboring operator’s signal on other frequencies?
The noise are spurious emission spikes. That means the amp isn't putting out a very clean signal and could interfere with adjacent stations. You could also be causing interference on the harmonics of those frequencies. For example 15 meters is a harmonic of 40 meters, so you could be splattering all over 15 meters and not even know it. Most of the bands tested with this amplifier were within FCC regulations as they were below the allowed threshold, and likely to not cause interference.
If you used a carbon filter over the antenna, would it make it any more purer. I have a life straw...would that work?
Now thats not a bad idea.
Yeah, well that is not as clean as one would like, but as you say it is certified. At the end of the day, now you know where it is dirty would you use it there?
Prob not. I'm never on 80 or 160 so it doesn't really matter to me. I sure would be disappointed if I got it for those bands though.
@@hamradiotube Problem solved then :-))
Please i don't have a spectrum analyzer, with what other instrument could I measure the noise of an antenna preamplifier? Thank you.
Not sure. I don't have a spectrum analyzer either. But I knew someone who did.
Purity of essence, of our precious bodily fluids
It's a little more pure than that lol
160m is the best winter season band. 130' wire with tuner does it.
I've not done too much 160 other than a few contacts last December for the AM contest. Don't think I'll be doing any with this amp though.
First, you need a clean signal source. Did you verify the purity of the transmitter's signal? Chinese ham equipment is notorious for poor filtering.
Yes, both the g90 and x5105 have been tested on the same equipment and are clean.
Can I cancel my order?
haha, no.
Dude, do you know what a G90 is? Otherwise a good review of the XPA125B.
Oh my god I misspoke. And yeah I have one of the more popular G90 videos on RUclips. You’ve prob seen it.
@@hamradiotube SNAP goes Mike!
Nice. 👍
Thanks 👍
Nice!!
Thanks for the visit
Neat!
I though it was pretty cool too. Thanks. 73
on the backe side they say 10-50mhz. becouse they Little bit bad ounder 10mhz
I will stick with the Acom. lol.
Well fine then :)
Looks like a X5105 not G90
You've got a good eye
Your over driving the amp on 160m
Could be. I was very new to amplifiers when I made this.
@@hamradiotube
You may want to make a comment or retraction or reshoot and add it to the end so people are not mislead
Not the best, but still better than a UV-5R. ;)
If only they would come out with the UV-5R HF version haha!
it's not G90 ;-)
lol
@@hamradiotube The transceiver connected to XPA125B looks like X5105. G90 has different form factor, smaller display, and the display is color OLED or backlit color TFT, while the transceiver in the picture has clearly an "old style" B/W LCD with gray background and its dimensions are greater than G90 display. I own a G90 and it definitely does not look like the rig you have in the video... What we did not see is how's the spectral purity of X5105 itself. Without that, you cannot say for sure that, for instance, the spurious IM products on 21 MHz are from X5105 or from XPA125B. It could be an interesting video but in fact there are too many unknown variables to make definite conclusions.
@@ok4rm Oh yes, that. That is what you call a slip of the tongue. But thanks for pointing it out. I'm very aware of the differences between the 2 radios as I own both. In fact, I have one of the more popular review videos on RUclips about the G90.