searching for interim zello solution

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Russell Purinton

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Jun 5, 2020, 7:39:58 AM6/5/20
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I see Zello API integration on the roadmap.

I have 1 instance of Zello working currently with SDRtrunk using Virtual Audio Cable.

I can create multiple VAC soundcards.  I have one for now.

I setup SDRtrunk to use VAC as it's output soundcard in Mono mode.  I setup Zello to use VAC as the Mic input and set it to Voice Activate PTT (VOX)

I set SDRtrunk to Listen to the Talkgroups I'm interested in and it works perfect.

I'm trying to find an interim solution to be able to send different talkgroups to different zello channels.

One idea I had was to install Icecast server locally, and connect SDRtrunk to that and stream the talkgroups I want,  then make a second VAC soundcard, and setup WinAmp to play thru that VAC then a second instance of Zello to record from that VAC...

Any other ideas?

Chance Lindsey

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Jun 5, 2020, 9:11:38 AM6/5/20
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Russell,

I was looking to do something similar. We have the professional Zello account, so I am not sure if it is available in the free version. In the API docs, there is a sample console application that will take audio files and upload them to a channel. It should be as simple as watching the recordings folder and running the console app for each new file that matches a set criteria. I'm not sure if it handles queueing....i.e. another file uploaded while the other is still playing. I hope to play around with it this weekend.

Checkout the support article: 

Chance

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Russell Purinton

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Jun 5, 2020, 10:07:40 PM6/5/20
to Chance Lindsey, sdrtrunk
It doesn’t appear that the free Zello includes that utility.

I found a work around involving Broadcastify calls api but it’s ugly.


On Jun 5, 2020, at 9:11 AM, Chance Lindsey <cha...@lindseyfamily.net> wrote:



Imago Trigger

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Jun 6, 2020, 11:20:31 PM6/6/20
to Russell Purinton, Chance Lindsey, sdrtrunk
is zello like discord or something?  its not a DNAS? curious

On Friday, June 5, 2020, Russell Purinton <russell....@gmail.com> wrote:
It doesn’t appear that the free Zello includes that utility.

I found a work around involving Broadcastify calls api but it’s ugly.


On Jun 5, 2020, at 9:11 AM, Chance Lindsey <cha...@lindseyfamily.net> wrote:


Russell,

I was looking to do something similar. We have the professional Zello account, so I am not sure if it is available in the free version. In the API docs, there is a sample console application that will take audio files and upload them to a channel. It should be as simple as watching the recordings folder and running the console app for each new file that matches a set criteria. I'm not sure if it handles queueing....i.e. another file uploaded while the other is still playing. I hope to play around with it this weekend.

Checkout the support article: 

Chance

On Fri, Jun 5, 2020 at 6:39 AM Russell Purinton <russell....@gmail.com> wrote:
I see Zello API integration on the roadmap.

I have 1 instance of Zello working currently with SDRtrunk using Virtual Audio Cable.

I can create multiple VAC soundcards.  I have one for now.

I setup SDRtrunk to use VAC as it's output soundcard in Mono mode.  I setup Zello to use VAC as the Mic input and set it to Voice Activate PTT (VOX)

I set SDRtrunk to Listen to the Talkgroups I'm interested in and it works perfect.

I'm trying to find an interim solution to be able to send different talkgroups to different zello channels.

One idea I had was to install Icecast server locally, and connect SDRtrunk to that and stream the talkgroups I want,  then make a second VAC soundcard, and setup WinAmp to play thru that VAC then a second instance of Zello to record from that VAC...

Any other ideas?

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Russell Purinton

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Jun 7, 2020, 8:18:53 AM6/7/20
to Imago Trigger, Chance Lindsey, sdrtrunk
It’s a PTT app where you can chat with up to 1000 people in a channel and only one person can talk at a time.  We have channels set to “listen only” mode and we play the scanner into Zello.

You can hear our scanner running now at 

I like it over DNAS for several reasons: 
1) Zello is real-time, there’s about 1 or 2 seconds delay versus DNAS and over a minute it seems.
2) Zello only uses data when messages are sent
3) Zello keeps a local history, for instant replay and message sharing 


On Jun 6, 2020, at 11:20 PM, Imago Trigger <imagot...@gmail.com> wrote:

is zello like discord or something?  its not a DNAS? curious

LordDonkey

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Jun 7, 2020, 8:26:56 AM6/7/20
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Zello is a push-to-talk walkie talkie app. It allows for real-time communication for work or personal purposes. You can use it to talk with your friends, co-workers, or dispatch a fleet. There are portable and mobile radios with Zello capability. There is also a radio gateway that allows the use of conventional radios with the Zello network.

Russell Purinton

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Jun 7, 2020, 8:45:15 AM6/7/20
to LordDonkey, sdrtrunk
I found a workaround for now.  I set SDRtrunk to play the police talk groups mono thru virtual audio cable 1 and set police Zello to record this.  Then I set the system default sound card to virtual audio cable 2 and opened up a Broadcastify Calls personal playlist with the fire channels and set fire Zello to record from that.

It is working but it is delayed more than the police feed for obvious reasons.   

Also this only works for 2 channels.  If I wanted to add a 3rd then I’m SOL.

Looking forward to Zello API integration where we can set it up like the other streaming options.  I am more than willing to be a Guinea pig, and I have dev experience so I may be able to help debug as well.

I am considering making a middleware between the Broadcastify Calls API and the Zello API myself, as it would be more elegant than my current work around.


On Jun 7, 2020, at 8:26 AM, LordDonkey <highvol...@gmail.com> wrote:


Zello is a push-to-talk walkie talkie app. It allows for real-time communication for work or personal purposes. You can use it to talk with your friends, co-workers, or dispatch a fleet. There are portable and mobile radios with Zello capability. There is also a radio gateway that allows the use of conventional radios with the Zello network.

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Imago Trigger

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Jun 7, 2020, 12:57:46 PM6/7/20
to Russell Purinton, LordDonkey, sdrtrunk
i was thinking of doing something similar with my sdrtrunk recordings and Discord sdrtrunk channel we are in but i dont think Discord owners will appreciate it!
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Ron Webb

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Jun 7, 2020, 2:04:27 PM6/7/20
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I am just curious, as I have zero experience with Zello, what it brings that would be better than something like IceCast. At the moment, I have an IceCast2 server set up and I create several different feeds based on talkgroups, such as one feed for my city police and another for fire. I can then use an app on my phone like Action Scanner Pro where I can create banks of feeds, so I can choose to listen ONLY to police traffic or ONLY fire traffic or both combined. Setting up my IceCast2 server was extremely easy for me, building it as a VM on an existing server, running many other VMs. It took me less than a half-hour to create and I'm able to route traffic over the Internet as well as locally on my local LAN for no cost.

I have gone to the Zello website to try to understand what it brings to the table but I guess it is an "outside the box" use that is being talked about here and I'm trying to figure out what that is. From the website, it appears to be an IP-based, push-to-talk audio network, similar to what we occasionally use at work; we have ESChat available for use. When first deployed, we used ESChat on an iPhone, which is not a good replacement for a traditional push-to-talk device. We now have a Sonim XP8, which should be a better physical platform for push-to-talk but they have not enabled the push-to-talk button on the side to work with ESChat. Our primary means of communication is an app that doesn't involve voice.

In case you are curious, I work for American Medical Response, the largest private ambulance service in the US. Although we are a large company, each local, operational area does things a little differently, so I'm only referring to how we do things in the Greater Sacramento region, which is not far different than other areas of Northern California. Because we work over a large, geographical area with vastly different terrain, maintaining our own radio network is a non-starter, hence why we end up using cellular networks. When I first started, we used Nextel, which worked OK for the most part, except we were required to use THEIR hardware. When Sprint took over Nextel and started shutting down what made Nextel unique is when we moved to ESChat, as it was hardware and carrier agnostic. We originally started using ESChat on an iPhone on the Verizon network but now have moved to the Sonim XP8 on FirstNet. I still have a Verizon iPhone and hoping to have it replaced with something on the FirstNet carrier as Verizon has pretty poor service where my office is located but receive a near-perfect signal on FirstNet on the Sonim and my personal iPhone.

Chance Lindsey

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Jun 7, 2020, 6:29:53 PM6/7/20
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Russell,

I found that using the Windows command tools was as simple as can be. At first I was confused on the support article, which links to the GitHub API Project. It turns out you don't need the API. The other missing part was the support article says Zello.exe.  For my ZelloWork install it was actually PTT.exe.  I can't imagine this not working with the free version.

To give it a test:

1. Install the Windows PC app. Either the Zello free from https://zello.com/personal/download/  or ZelloWork from your dashboard
2. Open a command prompt and go to the folder.  For me it was: cd \Program Files (x86)\ZelloWork
3. Either run Zello.exe or PTT.exe.
  ptt /contact="Test" /audio="C:\Users\Chance\SDRTrunk\recordings\20200607_171306GMRS_Simulcast_TRAFFIC__TO_411_FROM_7052301.wav"

contact is the name of the Zello channel. No user/pw is needed as it relies on what the Windows client app is already logged in as.

You'll need to make sure SDRTrunk is saving as WAV files and not MP3. Zello has no other option.
Running the command returns immediately after the upload and does not wait (or hang) for audio to finish playing, which is good.
It queues up the files just fine. No extra work was needed. I tested a 10 second clip, 10 times in a row.. Played 10 times on the channel.

In order to set up an interim solution until SDRTrunk has native functionality I plan to to write a simple C# program. I actually already do this now to upload audio to a Slack channel for Fire Station Alerts. C# and most other languages have a way to monitor the file system for new files added to a folder. Windows Task schedule might even include this. And there's probably freeware console apps that can do the same. As soon as a new file is added, it will simply run the above command line with the file name.

Chance


On Sun, Jun 7, 2020 at 5:34 AM Chris Hoffmann <chri...@gmail.com> wrote:
Hi Chance,

How did you get on with Zello sending recordings?

Russell Purinton

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Jun 7, 2020, 7:17:52 PM6/7/20
to Chance Lindsey, sdrtrunk
I see there’s an option to run a script on an alias, what would I put there to get it to pass the file name?

Kevin

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Jun 23, 2020, 12:57:04 PM6/23/20
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Ron,

One big difference that alot of people appreciate is  that Zello only uses data when a message is being received or sent. The other streaming options are a constant on type stream. So Zello would act more like a traditional radio instead of just playing a constant audio stream.

ProTip for any new Zello users that wish to give it a try, play with the settings. The iphone version is a little restricted but the others have tons of options you can change, audio alerts being a big one. I think the audio alerts is what turns alot of people off at first. For my Zello channels I have all the beeps turned off, if not they drive me crazy listening to my stream. For the channels I actually talk on, I have a few of them on.

Russell Purinton

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Jun 23, 2020, 1:28:26 PM6/23/20
to Kevin, sdrtrunk
A couple of other benefits to Zello is that it’s nearly real-time only a 1 second delay for me.  Shoutcast has a 1MB buffer so when running a low nitrate stream like 8k or 16k could result in a 2 minute delay.  

Also, I like that Zello stores a history of messages for instant replay and also allows you to export/share those messages with a simple link.

ZelloVOX is working great for me with SDRtrunk currently but we have the limitations of SDRtrunk only supporting a single sound card.  If we could get multi-sound card support and assign talkgroups to separate audio cards like we do now with streaming that would be great.    I’m not a huge fan of the way buffering is happening right now on the streams either...  example:

Dispatch to 101
Immediately 101 go ahead
30 second delay and then the message finally plays for 30 seconds.

Our dispatcher is made to repeat the call twice which means the dispatch might be 45 seconds long.  In this case we have a 45 second gap between the tones and the dispatch...

Does anyone know why SDRtrunk waits for the message to finish before starting to stream it?


On Jun 23, 2020, at 12:57 PM, Kevin <hinkl...@gmail.com> wrote:


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Kevin

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Jun 23, 2020, 2:35:43 PM6/23/20
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Also, to enable Radio Gateway mode open the Zello.config file and set "SetGatewayMode" to true. If anyone wants to poke around in that config file it has a bunch of different options in there, codec stuff, supernodes, etc. Other files in the directory reference 'Loudtalks' and port 443. Someone with more knowledge than myself may be able to do some nice tricks with whats there.

Russell Purinton

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Jun 24, 2020, 10:42:57 PM6/24/20
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so just a recap and a status on this...

The goal is to monitor a single P25 system with TG's for Fire and Police and to stream to seperate zello "Listen Only" channels for Fire and Police.

Doing a single channel is really straight forward.

Install Virtual Audio Cable, set sdr-trunk to play out through that in Mono mode.
Create a Playlist and Listen to the TG's you want.
Setup Zello to record from VACable, enable VOX mode.
Select the Channel and set VOX Switch On.

Done!

As messages play thru SDRtrunk, they are streamed to Zello in near real-time. Listening to Zello for me comes thru about a half second behind my handheld scanner. This is great.

So the complications come when you want to stream different talk groups to seperate channels.

Since SDRtrunk only supports a single soundcard output, the options are pretty limited without writing your own code.

There are of course ways to use Icecast for instance to stream to, then having something playing that stream, but I'm sure at this point we will be increasing the delay time far beyond the half second we have currently.

I was trying to stream to Broadcastify Calls platform and using their Personal Playlist player to play onto Zello, which works, with a delay, but the browser doesn't seem to survive more than 24 hours before I have to refresh the page.

For now I've conceded that Zello API integration might be a ways off, so I just ordered additional hardware so that I can run 2 instances of SDR Trunk.

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