Digital vs. Analog

If you are use to operating on analog FM repeaters, you will have noticed that the audio quality degrades as a station’s signal into the repeater (uplink) gets weaker; you start hearing an increase in noise bursts intermixed with the audio until the signal gets so weak that the station can no long access the repeater or you can not understand the audio because of noise. As you move further from the repeater you will start hearing the same noise bursts into your receiver as the repeater’s signal gets weaker (downlink) until you can no longer hear the repeater. A combination of a station’s weak signal into a repeater and a repeater’s weak signal to the listener can make the usability degrade faster.

The basic difference with digital repeaters is that the audio quality remains the same on the uplink and downlink until the very end of the coverage range; then the audio starts sounding broken (missing portions of the speech) on DMR systems caused by lost packets. The Internet can also drop the UDP packets used for moving traffic between repeaters and bridges, causing the same broken audio affect. Analog static is a thing of the past using DMR.

DMR has Forward Error Correction (FEC) which can correct small bit errors, slightly extending the usable range and improving communication quality.

Better quality receivers can operate at a lower noise floor, higher power transmitters, and higher gain antenna systems will also extend coverage of both analog and digital systems.

Review Connect Systems CS700 DMR Handheld

Let me start with a confession: personally I don’t care much about digital modes. That doesn’t mean that I don’t keep track of the latest technologies, and (hopefully) this short review is proof of that.

DMR I’m not going to explain in detail what DMR (Digital Mobile Radio) is, as there are many sources on the Internet that will do a much better job than I could.


Read More:
http://cs700dmr.blogspot.com

Connect Systems CS700 DMR Portable Radio va3xpr Review

The Connect Systems (CSI) CS700 portable radio is a low cost, high value Digital Mobile Radio (aka DMR) radio that has recently been released to the ham radio community. Overall, this is a great single band UHF DMR radio for ham radio use on the 70cm band and will make a great radio for anyone interested in getting started with DMR. At the time of this review, the pricing for a new CS700 directly from CSI was $180USD, which includes a 1-year warranty.

Price: $180USD
Author’s Rating: Excellent

(4 out of 5)
http://cs700dmr.blogspot.com

How to update Contacts in the CS-700 codeplug

Here's the writeup I did for our club as an intro, in case it works for anyone else.

Radio ID Database

Every DMR ham has a Radio ID assigned to them by DMR-MARC, which is where this database comes from.

(Request link is here: http://www.dmr-marc.net/request_subscriberID.html) This same Radio ID can be programmed into all your radios, since only one will Tx at a time. 

It’s maintained by a team of guys that do a great job with really fast turnaround on updates and new registration. 
  
The whole database is here:
http://cs700dmr.blogspot.com