There's been many cynics pick fault with DMR and various digital modes; citing things such as "Murmurmur That's not real radio, that's cheating putting it through internet voice links murmurmurmurmur!" and so on and so forth.
Yeah, that's all very well and good. Personally, I see it as another dimension for amateur radio and a different mode to try that should be exploited - as highlighted in my 'DMR - A love/hate relationship' blog posted earlier.
A friend of mine M6AIF decided to scurry off to my local hill with some VHF and UHF gear, and I had a brainwave:
Why not do a FM vs DMR simplex test?
I asked him to give me a shout on DH2 438.600mhz while I had the MD-380 running in the house, and he came through with a perfectly legible signal. Which is remarkable seeing as it had to fight with getting to the bottom of the hill to GOF towers, and getting through to 2 or 3 walls to my radio.
On SU19 433.475mhz it was a different story. I could barely copy him inside the house!
Intrigued, I decided to walk to a few streets away, find some clear space and perform an A/B comparison. The results can be found in the video below.
I believe DMR simplex can have some serious potential, as S1 of DMR signal is perfectly stable versus S1 of FM.
An FM signal would usually suffer from severe degradation (as seen in this video), while a DMR signal would be perfectly fine until it 'Goes a bit Max Headroom' and s..ssss...suff....suffer from sig....sig...signal...d..ddd.ddrop outs, and meets a steep signal cliff where it would go altogether.
Intriguing and compelling stuff.
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