Digital Vs. Analog Weak Signal Two-Way Radio Test
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- Опубліковано 4 лип 2024
- This is a complete test of all of the Digital and Analog modes for two way radio.
The test includes
DMR ( Digital Mobile Radio) , 7K60FXE
DSTAR (Icom's Digital voice mode for amateur radio)
P25 (Project 25) , 8K10F1E
Yaesu System Fusion C4FM DN 9K36F7W
Analog NARROW 2.5KHz Deviation, 11K2F3E
Analog WIDE 5KHz Deviation, 20K0F3E
The test was performed in a City Multi-path environment as well as a rugged terrain mountainous area to see what the limits of each mode were.
I used the 70cm / 440MHz ham band for the testing.
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73
Skyler W0SKY
Purchase a 900MHz radio for the 33cm ham band
w0sky.com/981 - Наука та технологія
I worked in a commercial 2-way shop for 27 years, been a ham for 50 and am quite familiar with video production. You did an amazing job syncing the audio and video! People don't know how hard this is. Also, it is the best comparo I've ever heard between the modes. Great job!
except for reusing the same video in both tests showing the same truck and signs at 13:18 and 14:52...
I've been waiting for a video like this for the longest time I've ever been able to find one that compares the different digital modes
Worth 100 thumbs up.
I appreciate all the work you put into this video. I love when people do comparison tests like this. VERY VALUABLE info to help new hams like myself decide what digital mode may serve me best and know what to expect while using it. Not very often you get to be on the receiving end to know what you sound like. - Ill be looking forward to more of your videos!
finally a real life test .... thankyou. a real eye opener
Finally we can see some real world tests
I own several repeaters and I would demonstrate this to skeptics. Two of the repeaters were using the same site, same antennas and same power. They were on a combiner with several other repeaters, P25 being their modes. I left out the Quantars, because they outperformed them all due to their output power being 110 Watts. The two repeaters that I used in my test were an analog wide band TKR-850 and the other was an XPR8400. DMR outperformed the analog repeater every time.
Define "outperformed". What were the metrics you used to come to this conclusion?
this is great, thank you for doing this, and great to see more videos from you. you have been an inspiration!
Well done and needed! I've been playing with all of these modes except for P25 and also find DMR and Fusion the clearest though not always reliable. That award goes to analog for me.
12:13 "a while ago" - you weren't kidding! ;) Thanks for the comparison, it was just what I was wondering.
Yeah I take like 3 year breaks between videos usually :p
@@SkylerF and 2 years between comment replies!
Skyler, Excellent Video. Thank you for taking the time to compile and disseminate the information and compare the various modes. 73~N8LWX
Hy Tyler,,, Great video. Excellent job.. Thank you and Jeremy for all of your hard work. great project... certainly tells the story. Jerry Dixon, KC0KW Kansas City Wide Fusion repeater group.
Superb comparison - thank you!
This is an excellent, real world test.
Excellent work! Regarding the comment that someone to drive for you would have been safer, I caught myself being a little bit nervous about that as well. But talking on the radio while driving is a staple for most of us even in a traffic-jammed metroplex. It’s not even hands-free for most mobiles!
Good point. Guess I need more friends. I did it on an early Sunday morning so the traffic wasn’t too horrible
finally a real-world test that actually makes sense
Thank you for joining us tonight and sharing this with W7HEN!
Nice Test Skyler, thanks for your time & effort!
Ken W0KAH
Hi Skyler! Glad to see you come back after a nice little hiatus!
You pickled a great topic to cover. I watch a LOT of amateur radio videos on UA-cam and don’t think I’ve encountered a video that compared the various ham-friendly digital modes the way you and your colleague did. Well done!
A couple of questions for you:
1. Were you using VHF or UHF for the testing?
2. While in downtown Denver, if I were to take a guess, it sounded like you were traveling away from the receive location. Would that be an accurate assumption?
While I’m partial to DMR, it was a tough call between DMR and P25 in terms of which had the better audio quality. I would tend to lean towards P25 in your testing. That is likely attributed to using a commercial Motorola radio for the P25 tests vs the TYT for DMR. Had you used a commercial (another Motorola XPR6550) DMR radio on your end of the test, I think that would have made the two almost indistinguishable.
Next in line in terms of audio quality would be D-Star followed by System Fusion easily a dead last. They both had a very robotic tin can sound to them which is likely the result of the poor implementation of compression.
Of course there have been advancements in more recent D-Star and System Fusion radios but budget is almost always a factor and it’s nice to see you continuing making the most of the gear in your collection!
Keep up the great work!
73,
-JeffH
W4JEW
Atlanta, GA
Thanks for the comment!
1. UHF 70cm All on the same simplex frequency for all tests
2. Yes Travelling away from receiver
For P25 I had a Moto radio on both ends
For DMR I had the TYT MD380 for TX and An XPR6550 for RX. I could not find two Moto DMR radios, so I decided to use the Moto for RX because the receivers are better in them.
ALso don't trust the second test I filmed a while ago as much because I was using Two MD380's for that one, no Moto
Skyler F thanks for the quick response!
Good job Skyler. We should have had lunch at the Ship's Tavern!
Listening on the Tech Net in S Nevada tonight. This is great stuff! Thanks for posting. de- W7MAG
Great video
Good job, Thank you
Very interesting video. Thanks
Brilliant. A great demo showing what we already know. Great cinematic elements!
Great video Skyler. This comparison video was long over due. Your next mission should you choose to accept it, is to compare the op25 open source vocoders to the hardware ones of say a thumbdv.
Lend me a ThumbDV and I’ll do it! All of my thumbDV’s are currently in use at my hub computer on our link
Great video, next time test out Yaesu Fusion Wide Mode, Thanks!
Just found this video after thinking of the beacon recovery video. Great comparison of what you can do with 5 or so watts. Cool to see how well DMR performed down in the noise. Next you should go up to 50 watts or more and test the curvature of the earth.
Thanks James, Yeah I'd like to do more tests like that. The only problem is finding stuff to do the videos, hard to find people to lend me stuff since I don't want to spend the $$ buying all the stuff just for a video. One test I want to do is 4 bands, 6 meters through 900MHz with the same gain antenna through mountains vs. city vs. farmland. Another test I want to do is comparing different mobile antennas in different environments by logging the received signal strength voltage on the receiver radio while mobile keyed up with a constant carrier.
@@SkylerF I'd like a test around the 70 cm band, as I am licensed in the GMRS band but I am looking to get my Technician class license.
Just a comment, for your P25 test, when was the last time the radios had a proper alignment? I find lots of P25 users who don't perform well just because the radio is out of alignment. On the Moto's, the deviation balance seems to be really key for good performance, and used 2-way moto gear have usually had tough lives in the field. Truthfully, P25 and Fusion should have been pretty close since Fusion is just bastardized P25 anyways...
The radios were on frequency, had proper deviation and good sensitivity in analog. That’s as far as I can go with my own equipment. I don’t have anything to test BER.
I think my radios might be using the older IMBE vocoder instead of AMBE2+ which might have something to do with it. Also P25 is similar to the fusion wide, which I did not test. Not over RF, but Fusion wide can be directly sampled to P25. Fusion narrow can be directly sampled to DMR through software without any vocoding.
@@SkylerF Ok, find someone local who can do alignments for you, it's more than just on frequency and "proper" deviation. You would be surprised how much better those radios will operate P25 when aligned properly...
Yeah that’s the way I need to go. Only so much I can do for a free video haha. I wanted to get people to send the latest and greatest new radios for each mode and then I ship back after the video was done but nobody was interested in that...
Overall good video. Have some suggestions for future tests if you ever want to revisit or try something similar again (coming from a fellow ham and wireless system engineer).
I want to make similar videos as time allows, and definatley am open to suggestions.
Although I prefer the audio on analog digital p25 seems to have good overall performance. Dmr a close second.
Nice job.....continue success OM 73 de Paul N0AH/3
Gotta get yourself an NXDN radio now :)
Great video. I'm still a big fan of analog. Working in the public safety field, the big difference between analog and digital has been on the fringe. Even though very scratchy you can make out the traffic vs digital which seems to be all or nothing/unreadable. Unfortunately advances in technology aren't always good moves.
Great work! Just curious, was the receive site for the mountainous terrain test the same as your urban test runs? Also, what was the approximate distance on both test runs?
The RX antenna was indoors maybe 2-3 miles away on the city test. The mountain test was a while ago when I was in socorro NM and the test was about 5-7 miles away on a magmount indoors. Antennas did not have a lot of height. I’m Not really testing range just testing weak signal
Understood. I just wanted to understand the test conditions a little better. Do you have Allstar? It would be great to have you talk about this on our tech net next Sunday night..
Yeah my hub is 46079 skyhublink.com
My 900Mhz repeater on lookout mountain near Denver is 40195, usually connected to the hub but I steer it around, that’s where I usually hang out
So you're putting wideband as 25k (~20k carrier width) and narrowband as 12.5k (10k carrier width) channel spacing?
Excellent video and production! de KA4EPS
Nice thumbnail big brother
Oh and I still think analog rules! :)
Agree, thanks for watching
Good thing about digital mode is the noise cancellation for the background, and there's no r1-r5 (qrk report that much) in digital when it's in range its r5 all the time
What antenna are you using for your mobile
Very good basic comparison video. I am planning on sharing it with my group as it is very "real world". On the analytical side, I would be interested in knowing more about the repeaters used. Were they all in the same location? Did they have the same antennas? Gain, Orientation, etc.
Did not use repeaters, this was all simplex directly from my moving vehicle to a stationary receive antenna doing the recording. The receiving end was just different radios being swapped out.
@@SkylerF Excellent. I must have missed that part. Again very good comparison experiment/video.
I guess I will stick with DMR for digital modes. Although the only digital HTs I have are cheapo Chinese ones.
Very nice test indeed. In my opinion, modulation was too low in analog narrow FM. While noise (the classic "whip effect" of multipath) was more or less the same as analog wide FM, it seems to me that modulation was far lower. Did you forget to turn the RX radio to narrow mode? Or did the RX radio have some issue with narrow bandwidth mode? (here I am refeerring to the test done in the city). Also, it actually seems that DMR is the best digital mode, the one that has less drop-outs in the test. Maybe it's just because the RX radio is better than the others? Anyway, while we all appreciate the absence of noise, I believe that actual readability of the signal is better in analog FM (wide). If, instead of a repetitive pattern (testing, 123) you had actually read out some random text (a book?) and asked for the other party to copy it, you should have clearly seen that analog wide FM is the best mode, that is, it allows to copy the most text without errors and omissions, even if the listener has to cope with the noise. 73 de IZ4UFQ
The RX radio bandwidth is right, I believe my TX modulation was too low on narrow, didn’t talk close enough to the mic.
As far as the digital modes.All of the radios had similar RX sensitivity on analog, but maybe one has worse bit error decode, there is no way I can test that unfortunateley. That may gave lead to the reason why fusion performed the worse, the fusion radios have the worst intermod rejection, and bieng in the city there may have been other signals generating intermod on my RX fusion radio.
Why did 5KHz fm sound better than 2.5KHz fm? Theoretically 2.5KHz deviation should have more RF power in a narrow spot and should sound louder. Or is it due to higher deviation that 5KHz was louder? Thanks for the amazing video.
"FM Improvement Factor". SNR/CNR. Each time you double the bandwidth you get 6db more signal but only 3db more noise at the receiver.
so for FM, more bandwidth is better
@@SkylerF Cool. Learned something new today. Thanks for the explanation otherwise I was comparing FM to SSB.
this is legit
Do M17 test plz on this TYT
Would have been interesting to examine ssb as well, probably not fair since it has a higher signal to noise but would have been interesting to see how it behaves in a City Environment. I'm not sure how the data is modulated for the various modes, but if done properly you can almost eliminate how noise and multi-path affects the data with data processing technique. This is why digital broadcast fm is so much less intereference prone than standard analog. A good write up is here if your into the math behind it all : theori.io/research/nrsc-5-c
Wow, digital is so much better compared to analog when it comes to multipath city environment. Out of all the digital modes, I would agree DMR had the best sound quality and signal. It would be curious to also try this test using NXDN.
For the rural mountain test, I would say it is a tossup because there were times the digital dropped out completely where the analog signal was still heard with noise.
What is the BER (Bit Error Rate) for the digital modes? This is the real measure for all digital modes.
Yeah, I wish I had a way to measure that, I don't have a communications system analyzer that does digital though :(. I'm not sure if there are even any service monitors that will modulate the amateur radio modes like Yaesu Fusion or DSTAR?
The other issue with my test is the radios probably have slightly varying RF performance based on the cost, so one mode may be better than another but the radios may have skewed it a different way based on the front end filtering etc...
P25 RULES! lol i love P25
Wow, analog narrow was so much worse compared to analog wide. On narrow you could barely copy anything but on wideband it was perfectly intelligible almost the entire time. Possibly the volume wasn't adjusted properly between the two tests since narrowband results in half the volume compared to wideband since the deviation is half as much.
P25 is the best
Digital is all or nothing
Even in a town environment, if you lose signal in digital, you may not jump back into it as soon as you would an analog. Signal lose can happen with any system, but the return to transmitting seems to be easier in analog. Now, on the security side of things, digital is better, but that is the only reason I personally think digital is better.
I agree with you on that. I also can’t stand the quality of digital after listening to it for a while. I much prefer picket fencing to digifarts
@@SkylerF I really want to like digital, I own and use some DTR moto and they are secure, but not much good for distance work. And if I need to call for help? No one would ever hear me.
The frequency wasn’t mentioned but on analog it sounds like it was done on 70cm.
yeah 70cm, same frequency for all radios. i put it in the description
There's no way to tell a frequency based on the "sound"
spatch713 Actually when you are mobile, the fluttering QSB becomes more rapid at a given speed. The wavelengths become shorter and the “dead spots” are closer together. When you get up to 10 GHz and higher the flutter is so rapid it becomes a modulated tone.
wecontrolthevideo well I'll be damned. Learn something new everyday.!
spatch713 Just listen to a weaker mobile signal sometime on UHF (440 MHz) especially if that mobile is moving 60 MPH or better, you’ll notice the rapid fading.
Digital wins on the fridges hands down
I expect P25 to be working much better as it's used by public safety agencies...
You should not have been operating the mobile radio while driving, you should have had two people in the vehicle, one driving and one operating
wtf ? you show a guy in the apt . A real test would be talking back and forth . what the hell is the guy in the apt doing ? maybe I do not want to know.
Talking back and forth would be a lot more complicated because then I would have to put a recorder on the vehicle and talk back and forth at the same time. We are simply testing each mode up against each other, and do not want any other variables in here to change. 1-way transmisions is enough to answer our questions on which mode works better for a weaker signal.
Jeremy, W0JRL was in the apartment, and he was switching all the radios out, starting / stopping the recording, and verifying the signal strength for me to find a good stretch of road to do the test. The apartment antenna was held still and each HT was swapped, because we did not want any variables to change.
@@SkylerF Good answer! And the signal back from the apartment would be inline with it's signal rx. The only variable would be the power going the other direction. I'm very happy to see a comparison of the different modes and find it useful here in the PNW with spotty coverage in certain areas I travel. When into the city I can use repeaters... But on the road home it twists and turns with trees and different elevations similar to Colorado. I f you have ever been to Pagosa Springs and travel between smaller towns you know!! Similar terrain here in Washington State. I find that Analog has become my friend with about 50 watts I am able to have somewhat reliable connectivity and in some spots turning on the compressor helps eliminate those deadish spots. Good SWR and high antennas are a must. I would like to try a test with DMR with the same watts I use (50) on DMR. The difficulty I have is my YL is not a ham... We use GMRS under my license. Similar results but GMRS is UHF and I have found VHF to be more stable at distances. Very good test and keep making vids!!!! 73's to all N7MWH