ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 2 [3] 4 5   Go Down

Author Topic: 2 way radios  (Read 4238 times)

Henry Cohen

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 623
  • Westchester Co., NY, USA
Re: 2 way radios
« Reply #20 on: June 08, 2017, 11:44:55 pm »


However I will disagree with you on TDMA transmitter function. The DMR subscriber units do in fact cycle the transmitter if operating on a repeater, same as P25-P2. This allows the subscriber to actually receive data in between TX bursts which enables advanced features such as transmit interrupt. It also has led to manufacturers claiming increased battery life. If there was a constant carrier from the subscriber, there would be no way to utilize the opposite timeslot as there would be RF contention. The DMR repeaters do transmit constant carrier if active on one or both timeslots, or in hang time or beacon.  The same cycling also occurs in M's proprietary Dual capacity Direct mode.

You are correct. I forgot that with a repeater the subscriber unit has to cycle the transmitter, as well as in dual direct mode. Thank you clarifying.

My experience has been that the DMR implementation of TDMA, along with improved audio equipment and practices, is less of a problem than the GSM TDMA. Then again, two-way radio subscriber units programmed only for conventional [digital] operation don't transmit a beacon at intervals the way phones do, so that tends to reduce the instances of RFI.
Logged
Henry Cohen

CP Communications    www.cpcomms.com
Radio Active Designs  www.radioactiverf.com

Andrew Broughton

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 926
    • Check Check One Two
Re: 2 way radios
« Reply #21 on: June 09, 2017, 09:34:30 pm »

The DTR 900MHz radio does eliminate the licensing issue, has terrific range and is overall a great radio but for the battery design IMO, a removable plastic cover and a cellphone style battery. The battery compartment door is too easily dropped, lost or broken. The only consideration is for any other 900-928MHz ISM equipment that might be on the event or installed in the venue: high power cordless phone system, machine-to-machine links (M2M for vending machines), HVAC remote control/monitoring, wireless DMX, rigging load cell monitoring, etc.
I have been using DTR radios for the past 4 years and have had no issues with the batteries or doors, but they have been in a controlled usage scenario. They have a range that is unbelievable for a 1 watt radio - easily outpacing the 4-watt CP200s they replaced. I honestly have never encountered a radio with the range that these things have. The free programming software and license-free operation along with their relatively low price and small size makes them a unique product for anyone interested in a digital radio system.
If anyone wants to know more about the DTR radios, my website (see my sig) has the most up to date and complete information available on the internet. I also have an inexpensive (previously enjoyed) turnkey touring package available for sale - contact me at my website if you're interested.

(Oh - I'm just changing hosts ATM, so if my website 404's you, feel free to PM me of course!)
« Last Edit: June 09, 2017, 09:39:51 pm by Andrew Broughton »
Logged
-Andy

"Well, my days of not taking you seriously are certainly coming to a middle..."

http://www.checkcheckonetwo.com
Saving lives through Digital Audio, Programming and Electronics.

Mark Hannah

  • Newbie
  • *
  • Offline Offline
  • Posts: 18
Re: 2 way radios
« Reply #22 on: July 13, 2017, 07:07:18 pm »

I'm concentrating on digital radio offerings, and DMR in particular for a few reasons: a) At this durability/performance/reliability level and expected ROI, you're looking at the same general pricing as an analog only radio; b) These radios provide the option of operating in either conventional analog mode or digital on a per channel basis, which means backward compatibility and compatibility with most of the available rental inventory; c) Digital radios offer a number of advantages in spectral efficiency, range, less susceptibility to co-channel interference, and channel loading.

I find the digital option on our CP200d almost unusable.  The sound quality is bad (no clarity through radio's speaker or remote speaker).  The latency is my biggest complaint.  I looked in the manual, but couldn't find what the expected latency should be.  What should I be expecting?
Logged

Tom Provenza

  • Newbie
  • *
  • Offline Offline
  • Posts: 39
Re: 2 way radios
« Reply #23 on: July 13, 2017, 09:56:35 pm »

I find the digital option on our CP200d almost unusable.  The sound quality is bad (no clarity through radio's speaker or remote speaker).  The latency is my biggest complaint.  I looked in the manual, but couldn't find what the expected latency should be.  What should I be expecting?

Are these radios simplex or is there network infrastructure involved? I would venture to say something is not right if it is as bad as you suggest. Most LMR users would have a hard time going back to analog after getting accustomed to the digital audio. There should be no audible latency to most users...although this group would be the exception  ::)
Logged
------------------

Tom Provenza

Mark Hannah

  • Newbie
  • *
  • Offline Offline
  • Posts: 18
Re: 2 way radios
« Reply #24 on: July 14, 2017, 12:33:14 pm »

Are these radios simplex or is there network infrastructure involved? I would venture to say something is not right if it is as bad as you suggest. Most LMR users would have a hard time going back to analog after getting accustomed to the digital audio. There should be no audible latency to most users...although this group would be the exception  ::)

They are simplex w/ no extra infrastructure.

If no one is around me and I'm communicating with another part of the venue area (for example, Monitors to FOH), then the latency doesn't bother me (just the audio quality).  If another radio is in audible range and I'm transmitting, then it is very distracting to me.  Less so if another person is transmitting, but still...

If people are curious and it helps me find out if I need to go back to the vendor/programmer, then I'll get a rough latency the next time I use the radios.  I'd rather not pull a guess out of no where.
Logged

Tom Provenza

  • Newbie
  • *
  • Offline Offline
  • Posts: 39
Re: 2 way radios
« Reply #25 on: July 14, 2017, 02:27:19 pm »

They are simplex w/ no extra infrastructure.

If no one is around me and I'm communicating with another part of the venue area (for example, Monitors to FOH), then the latency doesn't bother me (just the audio quality).  If another radio is in audible range and I'm transmitting, then it is very distracting to me.  Less so if another person is transmitting, but still...

If people are curious and it helps me find out if I need to go back to the vendor/programmer, then I'll get a rough latency the next time I use the radios.  I'd rather not pull a guess out of no where.


If simplex, there is not much in the radio codeplug that could impact it.  this will probably come down to subjectiveness on both issues. I will pull out a few radios this weekend and see if I can come up with a delay measurement just for kicks. There is definitely delay inherent to the vocoding process but I never put much thought into it before.
Logged
------------------

Tom Provenza

lindsay Dean

  • Classic LAB
  • Sr. Member
  • *
  • Offline Offline
  • Posts: 452
Re: 2 way radios
« Reply #26 on: July 14, 2017, 02:40:11 pm »

 I second the rdu 4100. tough as stainless steel nails.
 you also have a cloning function
once you program one you can set the lone master in one base set the other in the other base, easy cloning.
Logged
"A mans got to know his limitations"
     and Pray for higher guidance

David Lim

  • Newbie
  • *
  • Offline Offline
  • Posts: 4
Re: 2 way radios
« Reply #27 on: August 09, 2017, 05:11:41 pm »

Hey guys, following this thread, as I'm looking for some radios also. Just want to make sure I have a few things correct:
1. Motorola DTR radios CAN'T work together with something like the CP200, correct? So buying a few DTRs and renting CP's for expanded tour crew would be a no-go, right?
2. If I go the UHF route, like a CP200 or the Hytera PD5, is there a limit to how many you have before you need a license? Or when you buy even 1, you need it?
3. Going through Forest Industries, for example, I could buy a license, but then I'd have to program myself?

Thanks!
Logged
DavidL

Rob Spence

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2396
  • Boston Metro North/West
    • Lynx Audio Services
Re: 2 way radios
« Reply #28 on: August 09, 2017, 06:24:28 pm »

Hey guys, following this thread, as I'm looking for some radios also. Just want to make sure I have a few things correct:
1. Motorola DTR radios CAN'T work together with something like the CP200, correct? So buying a few DTRs and renting CP's for expanded tour crew would be a no-go, right?
2. If I go the UHF route, like a CP200 or the Hytera PD5, is there a limit to how many you have before you need a license? Or when you buy even 1, you need it?
3. Going through Forest Industries, for example, I could buy a license, but then I'd have to program myself?

Thanks!

To answer #2

Depending on the frequency, you need a license to transmit. Period. You can listen without one. The number of units isn't important. In fact, you are likely only transmitting on one radio at any given time.

There are frequencies that do not need a license but they tend to be crowded and have very strict requirements for low transmit power.




Sent from my iPad using Tapatalk HD
Logged
rob at lynxaudioservices dot com

Dealer for: AKG, Allen & Heath, Ashley, Astatic, Audix, Blue Microphones, CAD, Chauvet, Community, Countryman, Crown, DBX, Electro-Voice, FBT, Furman, Heil, Horizon, Intellistage, JBL, Lab Gruppen, Mid Atlantic, On Stage Stands, Pelican, Peterson Tuners, Presonus, ProCo, QSC, Radial, RCF, Sennheiser, Shure, SKB, Soundcraft, TC Electronics, Telex, Whirlwind and others

Henry Cohen

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 623
  • Westchester Co., NY, USA
Re: 2 way radios
« Reply #29 on: August 09, 2017, 06:29:18 pm »

Hey guys, following this thread, as I'm looking for some radios also. Just want to make sure I have a few things correct:
1. Motorola DTR radios CAN'T work together with something like the CP200, correct? So buying a few DTRs and renting CP's for expanded tour crew would be a no-go, right?
Correct.


Quote
2. If I go the UHF route, like a CP200 or the Hytera PD5, is there a limit to how many you have before you need a license? Or when you buy even 1, you need it?
Quantity is not relevant to the need for an FCC license. To operate business band two-way radios requires a license, whatever the quantity.


Quote
3. Going through Forest Industries, for example, I could buy a license, but then I'd have to program myself?
Either you could program the radios if you have the software and programming cable, or take the radios, along with a copy of your license, to your dealer or other radio shop for programming.
Logged
Henry Cohen

CP Communications    www.cpcomms.com
Radio Active Designs  www.radioactiverf.com
Pages: 1 2 [3] 4 5   Go Up
 


Page created in 0.1 seconds with 17 queries.