# Simulcast buffer value issue

**URL:** https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998
**Category:** AllStarLink
**Created:** [February 13, 2018, 9:43am UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998 "2018-02-13T09:43:42Z")
**Posts on this page:** 20
**Page:** 1

<div class="post-metadata">

### Author: ![VK7HH](https://community.allstarlink.org/user_avatar/community.allstarlink.org/vk7hh/32/857_2.png) [@VK7HH](https://community.allstarlink.org/u/VK7HH)
#### Post date: [February 13, 2018, 9:43am UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/1 "2018-02-13T09:43:42Z")

</div>

Interesting thoughts Tim... perhaps worth documenting on the wiki?  
Even though it was just "in theory", what kind of sync error was it?  
Were we talking microseconds or even more?

I have a receiver on a yagi pointed at a distant simulcasted site. I  
have noticed on occasion, I can hear the distant simulcasted site  
start to send audio underneath the carrier of the site that is closest  
(and strongest to me). The distant site is also the master site, and  
has the lowest latency, but I'm talking two words worth of audio is  
send before my other site starts sending audio. Once they are both  
transmitting, I have not noticed any timing issues (i.e. distortion  
etc). I'm not sure if this issue was related to what I posted  
previously about the variable audio delay on unkey.

I'm running app\_rpt on a Raspberry Pi using a cut down image we use here in VK.

[http://vklink.com.au](http://vklink.com.au)

"When simulcasting the audio from all (non captured) transmitters needs to  
arrive at the receiver with in an acceptable time frame (80 us). The DAC  
theory was that it didn't start sending audio at correct clock cycle every  
time. That would cause the audio to be out of sync between RTCMs causing  
simulcast distortion.

As I said, that was the theory. The new theory is that the external clock  
source was causing the DAC to trigger inappropriately. I spoke with someone  
I met here on the list (Kevin I think its was) who is using a different  
external clock and reports perfect simulcast operations"

---

<div class="post-metadata">

### Author: ![Ve7lyd](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/v/ecae2f/32.png) [@Ve7lyd](https://community.allstarlink.org/u/Ve7lyd)
#### Post date: [February 14, 2018, 5:56pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/2 "2018-02-14T17:56:26Z")

</div>

Hey,

What radios are you using for the Tx?

Jesse

> **···**
>
> On Tue, Feb 13, 2018 at 1:43 AM, Hayden Honeywood [haydenph91@gmail.com](mailto:haydenph91@gmail.com) wrote:
> 
> > * * *
> > 
> > App\_rpt-users mailing list
> > 
> > [App\_rpt-users@lists.allstarlink.org](mailto:App_rpt-users@lists.allstarlink.org)
> > 
> > [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users)
> > 
> > To unsubscribe from this list please visit [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users) and scroll down to the bottom of the page. Enter your email address and press the “Unsubscribe or edit options button”
> > 
> > You do not need a password to unsubscribe, you can do it via email confirmation. If you have trouble unsubscribing, please send a message to the list detailing the problem.
> 
> ```auto
> Interesting thoughts Tim... perhaps worth documenting on the wiki? Even though it was just "in theory", what kind of sync error was it? Were we talking microseconds or even more?
> 
> ```
> 
> ```auto
> I have a receiver on a yagi pointed at a distant simulcasted site. I have noticed on occasion, I can hear the distant simulcasted site start to send audio underneath the carrier of the site that is closest (and strongest to me). The distant site is also the master site, and has the lowest latency, but I'm talking two words worth of audio is send before my other site starts sending audio. Once they are both transmitting, I have not noticed any timing issues (i.e. distortion etc). I'm not sure if this issue was related to what I posted previously about the variable audio delay on unkey.
> 
> ```
> 
> ```auto
> I'm running app_rpt on a Raspberry Pi using a cut down image we use here in VK.
> 
> ```
> 
> ```auto
> [http://vklink.com.au](http://vklink.com.au)
> 
> ```
> 
> ```auto
> 
> ```
> 
> ```auto
> 
> "When simulcasting the audio from all (non captured) transmitters needs to
> arrive at the receiver with in an acceptable time frame (80 us). The DAC
> theory was that it didn't start sending audio at correct clock cycle every
> time. That would cause the audio to be out of sync between RTCMs causing
> simulcast distortion.
> As I said, that was the theory. The new theory is that the external clock
> source was causing the DAC to trigger inappropriately. I spoke with someone
> I met here on the list (Kevin I think its was) who is using a different
> external clock and reports perfect simulcast operations"
> 
> ```

---

<div class="post-metadata">

### Author: ![VK7HH](https://community.allstarlink.org/user_avatar/community.allstarlink.org/vk7hh/32/857_2.png) [@VK7HH](https://community.allstarlink.org/u/VK7HH)
#### Post date: [February 14, 2018, 10:09pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/3 "2018-02-14T22:09:53Z")

</div>

In response to Jeff's issue - make sure your RTCM's 9.6MHz clock is GPS  
locked. Both Joe KC2IRV and myself have confirmed that, although using  
OCXO's by themselves work, they aren't perfect and move around. If you  
still have the little crystal in there, that will be the major source of  
your issues, it is nowhere near stable enough.

Fix the overlap issues to where a majority of your users are, don't worry  
about mobiles, it will just sound mostly like multipathing to them, if done  
right. Fixed stations really suffer the most in bad overlap areas.

Jesse - I use a radio base called Unilab/Stanillite KL series. They come in  
KL70 (can be modded to 50MHz), KL150 (for 2m), KL450 (for 70cm) and KL850.  
I'm pretty sure they were exclusive to the Australian market.  
I've got all my audios set up the same, straight into the modulator diode.  
All freq response is exactly the same, and levels set the same.

The issue doesn't appear to be audio related but software related as per  
Tim's post earlier. My Pi does run at 100mbps though, perhaps I should be  
forcing that down to 10mbps as a start. I'm just not sure why changing the  
simulcast launch delay causes the issue, at least on the surface to be  
worse when that's on a per board basis back at the TX sites.

Hayden

---

<div class="post-metadata">

### Author: ![VK7HH](https://community.allstarlink.org/user_avatar/community.allstarlink.org/vk7hh/32/857_2.png) [@VK7HH](https://community.allstarlink.org/u/VK7HH)
#### Post date: [February 15, 2018, 9:36pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/4 "2018-02-15T21:36:11Z")

</div>

Starting to drift off topic.... however...

Attached are my simulcast Radio Mobile plots for the two site system I have.

Sam - I'm currently using the BG7TBL GPSDO's that are readily available on  
eBay. They give both a 10MHz output and a 1PPS. I then use a board that Joe  
KC2IRV developed that uses a 10MHz signal from the GPS to control the VTune  
pin on a 9.6MHz OCXO.

[http://rtcmsimulcast.wikifoundry.com/page/9.6+MHz+PLL+Circuit+for+RTCM](http://rtcmsimulcast.wikifoundry.com/page/9.6+MHz+PLL+Circuit+for+RTCM)

Back to the one of the topics of the thread -  
I was driving home within the overlap area of the sites again, and noticed  
that extra "audio delay" to my secondary site. The audio starts first on  
the main site, few words later, the audio starts on the secondary site...  
it's quite weird...  
Can I attach MP3's to the list here? I might try to obtain an example.

The variable delay on unkeying is still a problem too.

 ![](https://community.allstarlink.org/uploads/default/original/1X/e2be076ec0297cdb5ec0332f7df34b1b18bd5f76.jpeg)

---

<div class="post-metadata">

### Author: ![Kj6qfs](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/k/ba8739/32.png) [@Kj6qfs](https://community.allstarlink.org/u/Kj6qfs)
#### Post date: [February 15, 2018, 9:47pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/5 "2018-02-15T21:47:01Z")

</div>

Very good, Hayden. Yes, I’ve been in touch with Joe about his project from when he ordered the RTCMs. I was inquiring as to what Jeff was running. Didn’t mean to veer off topic.

> **···**
>
> Starting to drift off topic… however…
> 
> Attached are my simulcast Radio Mobile plots for the two site system I have.
> 
> Sam - I’m currently using the BG7TBL GPSDO’s that are readily available on eBay. They give both a 10MHz output and a 1PPS. I then use a board that Joe KC2IRV developed that uses a 10MHz signal from the GPS to control the VTune pin on a 9.6MHz OCXO.
> 
> [http://rtcmsimulcast.wikifoundry.com/page/9.6+MHz+PLL+Circuit+for+RTCM](http://rtcmsimulcast.wikifoundry.com/page/9.6+MHz+PLL+Circuit+for+RTCM)
> 
> Back to the one of the topics of the thread -
> 
> I was driving home within the overlap area of the sites again, and noticed that extra “audio delay” to my secondary site. The audio starts first on the main site, few words later, the audio starts on the secondary site… it’s quite weird…
> 
> Can I attach MP3’s to the list here? I might try to obtain an example.
> 
> The variable delay on unkeying is still a problem too.
> 
> KJ6QFS  
> Sam Skolfield

---

<div class="post-metadata">

### Author: ![K5cg](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/k/8797f3/32.png) [@K5cg](https://community.allstarlink.org/u/K5cg)
#### Post date: [February 15, 2018, 10:44pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/6 "2018-02-15T22:44:46Z")

</div>

It appears that [sip.allstarlink.org](http://sip.allstarlink.org) is no longer a valid DNS hostname. I am able to SIP connect using the .178 IP address.

> **···**
>
> 73
> 
> Danny
> 
> K5CG

---

<div class="post-metadata">

### Author: ![W9CR](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/w/ecae2f/32.png) [@W9CR](https://community.allstarlink.org/u/W9CR)
#### Post date: [February 15, 2018, 11:12pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/7 "2018-02-15T23:12:45Z")

</div>

I have a few PCGM's that I never used, if anyone needs a few please send me a  
direct email.

Thank you,

> **···**
>
> On 2/14/18 5:09 PM, Hayden Honeywood wrote:
> 
> > In response to Jeff's issue - make sure your RTCM's 9.6MHz clock is GPS  
> > locked. Both Joe KC2IRV and myself have confirmed that, although using OCXO's  
> > by themselves work, they aren't perfect and move around. If you still have the  
> > little crystal in there, that will be the major source of your issues, it is  
> > nowhere near stable enough.
> 
> --  
> Bryan Fields
> 
> 727-409-1194 - Voice  
> [http://bryanfields.net](http://bryanfields.net)

---

<div class="post-metadata">

### Author: ![VK7HH](https://community.allstarlink.org/user_avatar/community.allstarlink.org/vk7hh/32/857_2.png) [@VK7HH](https://community.allstarlink.org/u/VK7HH)
#### Post date: [February 15, 2018, 11:26pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/8 "2018-02-15T23:26:34Z")

</div>

No worries Jeff and Sam.

It would be great to get a forum type discussion happening for simulcast.  
The mailing list I guess is still sufficient.  
What are you using to lock your RTCM's to 9.6MHz? If it's just the internal  
crystal still in there, then this is nowhere near sufficient, and will  
cause the audio to drift around like crazy.  
You need some form of stable frequency reference that is the same between  
sites (i.e. GPS, OCXO etc)

I think from a previous posting the PCGM's had issues with creating a whole  
lot of noise and crud, could be wrong. Although mounting in a shielded  
enclosure probably helps. The board Joe came up with only requires a  
handful of parts and an OCXO.... he was also experimenting with the Leo  
Bondar programmable GPS unit, although this doesn't give out the 1PPS, so  
you'd effectively need two GPS units at the site.

The network I run on my simulcast system is via the internet, not via  
direct links as we don't have a path between sites. The internet is a  
business grade connection with low (\<35mS) latency to the slowest site.

---

<div class="post-metadata">

### Author: ![tsawyer](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/t/eb8c5e/32.png) [@tsawyer](https://community.allstarlink.org/u/tsawyer)
#### Post date: [February 15, 2018, 11:27pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/9 "2018-02-15T23:27:40Z")

</div>

I’ve never heard one transmitter come up before another. I seen long delays but on all RTCMs at the same. Are your RTCMs connected to the same node number?

> **···**
>
> On Thu, Feb 15, 2018 at 1:36 PM, Hayden Honeywood [haydenph91@gmail.com](mailto:haydenph91@gmail.com) wrote:
> 
> > * * *
> > 
> > App\_rpt-users mailing list
> > 
> > [App\_rpt-users@lists.allstarlink.org](mailto:App_rpt-users@lists.allstarlink.org)
> > 
> > [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users)
> > 
> > To unsubscribe from this list please visit [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users) and scroll down to the bottom of the page. Enter your email address and press the “Unsubscribe or edit options button”
> > 
> > You do not need a password to unsubscribe, you can do it via email confirmation. If you have trouble unsubscribing, please send a message to the list detailing the problem.
> 
> –
> 
> Starting to drift off topic… however…
> 
> Attached are my simulcast Radio Mobile plots for the two site system I have.
> 
> Sam - I’m currently using the BG7TBL GPSDO’s that are readily available on eBay. They give both a 10MHz output and a 1PPS. I then use a board that Joe KC2IRV developed that uses a 10MHz signal from the GPS to control the VTune pin on a 9.6MHz OCXO.
> 
> [http://rtcmsimulcast.wikifoundry.com/page/9.6+MHz+PLL+Circuit+for+RTCM](http://rtcmsimulcast.wikifoundry.com/page/9.6+MHz+PLL+Circuit+for+RTCM)
> 
> Back to the one of the topics of the thread -
> 
> I was driving home within the overlap area of the sites again, and noticed that extra “audio delay” to my secondary site. The audio starts first on the main site, few words later, the audio starts on the secondary site… it’s quite weird…
> 
> Can I attach MP3’s to the list here? I might try to obtain an example.
> 
> The variable delay on unkeying is still a problem too.
> 
> Tim WD6AWP

---

<div class="post-metadata">

### Author: ![VK7HH](https://community.allstarlink.org/user_avatar/community.allstarlink.org/vk7hh/32/857_2.png) [@VK7HH](https://community.allstarlink.org/u/VK7HH)
#### Post date: [February 15, 2018, 11:28pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/10 "2018-02-15T23:28:55Z")

</div>

Joe's video is a good starting point to describe what is going on -

---

<div class="post-metadata">

### Author: ![tsawyer](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/t/eb8c5e/32.png) [@tsawyer](https://community.allstarlink.org/u/tsawyer)
#### Post date: [February 15, 2018, 11:30pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/11 "2018-02-15T23:30:33Z")

</div>

Sorry to say this, but those are the bad external clock source I mentioned in another post.They are also very dirty. I know one person who’s equipment was turned off by the site manager due to PCGM interferance.

> **···**
>
> On Thu, Feb 15, 2018 at 3:12 PM, Bryan Fields [Bryan@bryanfields.net](mailto:Bryan@bryanfields.net) wrote:
> 
> > On 2/14/18 5:09 PM, Hayden Honeywood wrote:
> > 
> > > In response to Jeff’s issue - make sure your RTCM’s 9.6MHz clock is GPS
> > 
> > > locked. Both Joe KC2IRV and myself have confirmed that, although using OCXO’s
> > 
> > > by themselves work, they aren’t perfect and move around. If you still have the
> > 
> > > little crystal in there, that will be the major source of your issues, it is
> > 
> > > nowhere near stable enough.
> > 
> > I have a few PCGM’s that I never used, if anyone needs a few please send me a
> > 
> > direct email.
> > 
> > Thank you,
> > 
> > –
> > 
> > Bryan Fields
> > 
> > 727-409-1194 - Voice
> > 
> > [http://bryanfields.net](http://bryanfields.net)
> > 
> > * * *
> > 
> > App\_rpt-users mailing list
> > 
> > [App\_rpt-users@lists.allstarlink.org](mailto:App_rpt-users@lists.allstarlink.org)
> > 
> > [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users)
> > 
> > To unsubscribe from this list please visit [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users) and scroll down to the bottom of the page. Enter your email address and press the “Unsubscribe or edit options button”
> > 
> > You do not need a password to unsubscribe, you can do it via email confirmation. If you have trouble unsubscribing, please send a message to the list detailing the problem.
> 
> –
> 
> Tim WD6AWP

---

<div class="post-metadata">

### Author: ![VK7HH](https://community.allstarlink.org/user_avatar/community.allstarlink.org/vk7hh/32/857_2.png) [@VK7HH](https://community.allstarlink.org/u/VK7HH)
#### Post date: [February 15, 2018, 11:31pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/12 "2018-02-15T23:31:22Z")

</div>

Hi Tim,  
Yes, they are all connected to the same node number.  
I'll get recording of what it sounds like and post here. That is issue 1)

Issue 2) is the variable delay on ALL the RTCM's as you describe. I might  
start talking on the repeater with a little echo delay on unkey, then a few  
overs later the delay might have ballooned out to 1-2 seconds.

---

<div class="post-metadata">

### Author: ![W9CR](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/w/ecae2f/32.png) [@W9CR](https://community.allstarlink.org/u/W9CR)
#### Post date: [February 15, 2018, 11:41pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/13 "2018-02-15T23:41:00Z")

</div>

Well for setting the 9.6 MHz clock onthe RTCM, it's likely ok. Using it for  
the PLL reference would not be advised unless you look at it and it's clean.

I've never used them for that.

> **···**
>
> On 2/15/18 6:30 PM, Tim Sawyer wrote:
> 
> > Sorry to say this, but those are the bad external clock source I mentioned in  
> > another post.They are also very dirty. I know one person who's equipment was  
> > turned off by the site manager due to PCGM interferance.
> 
> --  
> Bryan Fields
> 
> 727-409-1194 - Voice  
> [http://bryanfields.net](http://bryanfields.net)

---

<div class="post-metadata">

### Author: ![VK7HH](https://community.allstarlink.org/user_avatar/community.allstarlink.org/vk7hh/32/857_2.png) [@VK7HH](https://community.allstarlink.org/u/VK7HH)
#### Post date: [February 15, 2018, 11:53pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/14 "2018-02-15T23:53:49Z")

</div>

Where in Radio Mobile online is the ability to select the delay? It might  
be right in front of my eyes, but I can't see it.

---

<div class="post-metadata">

### Author: ![radiotech655](https://community.allstarlink.org/user_avatar/community.allstarlink.org/radiotech655/32/3930_2.png) [@radiotech655](https://community.allstarlink.org/u/radiotech655)
#### Post date: [February 15, 2018, 11:58pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/15 "2018-02-15T23:58:53Z")

</div>

If you provide me with your site information I can run a study in EDX, which is a commercial product.

Kevin J. Babich

219.406.9707 Mobile

\*\*\*Mobile EMail\*\*\*

Please excuse any typos and brevity.

> **···**
>
> > On Feb 15, 2018, at 5:53 PM, Hayden Honeywood \<haydenph91@gmail.com\> wrote:
> > 
> > Where in Radio Mobile online is the ability to select the delay? It might be right in front of my eyes, but I can't see it.
> > 
> > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_  
> > App\_rpt-users mailing list  
> > App\_rpt-users@lists.allstarlink.org  
> > [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users)
> > 
> > To unsubscribe from this list please visit [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users) and scroll down to the bottom of the page. Enter your email address and press the "Unsubscribe or edit options button"  
> > You do not need a password to unsubscribe, you can do it via email confirmation. If you have trouble unsubscribing, please send a message to the list detailing the problem.

---

<div class="post-metadata">

### Author: ![tsawyer](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/t/eb8c5e/32.png) [@tsawyer](https://community.allstarlink.org/u/tsawyer)
#### Post date: [February 16, 2018, 12:02am UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/16 "2018-02-16T00:02:45Z")

</div>

The on line version does not have it. In the PC version I think you choose an “interferance” plot… maybe, it’s bee a long time.

> **···**
>
> On Thu, Feb 15, 2018 at 3:53 PM, Hayden Honeywood [haydenph91@gmail.com](mailto:haydenph91@gmail.com) wrote:
> 
> > * * *
> > 
> > App\_rpt-users mailing list
> > 
> > [App\_rpt-users@lists.allstarlink.org](mailto:App_rpt-users@lists.allstarlink.org)
> > 
> > [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users)
> > 
> > To unsubscribe from this list please visit [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users) and scroll down to the bottom of the page. Enter your email address and press the “Unsubscribe or edit options button”
> > 
> > You do not need a password to unsubscribe, you can do it via email confirmation. If you have trouble unsubscribing, please send a message to the list detailing the problem.
> 
> –
> 
> Where in Radio Mobile online is the ability to select the delay? It might be right in front of my eyes, but I can’t see it.
> 
> Tim WD6AWP

---

<div class="post-metadata">

### Author: ![tsawyer](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/t/eb8c5e/32.png) [@tsawyer](https://community.allstarlink.org/u/tsawyer)
#### Post date: [February 16, 2018, 12:07am UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/17 "2018-02-16T00:07:30Z")

</div>

It was only being used for clocking the RTCM. I believe the problem is power circuitry radiates bunches of hash and trash. It was interfering with something on VHF high band, like 173.050… somewhere near there.

> **···**
>
> On Thu, Feb 15, 2018 at 3:41 PM, Bryan Fields [Bryan@bryanfields.net](mailto:Bryan@bryanfields.net) wrote:
> 
> > On 2/15/18 6:30 PM, Tim Sawyer wrote:
> > 
> > > Sorry to say this, but those are the bad external clock source I mentioned in
> > 
> > > another post.They are also very dirty. I know one person who’s equipment was
> > 
> > > turned off by the site manager due to PCGM interferance.
> > 
> > Well for setting the 9.6 MHz clock onthe RTCM, it’s likely ok. Using it for
> > 
> > the PLL reference would not be advised unless you look at it and it’s clean.
> > 
> > I’ve never used them for that.
> > 
> > –
> > 
> > Bryan Fields
> > 
> > 727-409-1194 - Voice
> > 
> > [http://bryanfields.net](http://bryanfields.net)
> > 
> > * * *
> > 
> > App\_rpt-users mailing list
> > 
> > [App\_rpt-users@lists.allstarlink.org](mailto:App_rpt-users@lists.allstarlink.org)
> > 
> > [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users)
> > 
> > To unsubscribe from this list please visit [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users) and scroll down to the bottom of the page. Enter your email address and press the “Unsubscribe or edit options button”
> > 
> > You do not need a password to unsubscribe, you can do it via email confirmation. If you have trouble unsubscribing, please send a message to the list detailing the problem.
> 
> –
> 
> Tim WD6AWP

---

<div class="post-metadata">

### Author: ![W9CR](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/w/ecae2f/32.png) [@W9CR](https://community.allstarlink.org/u/W9CR)
#### Post date: [February 16, 2018, 7:12pm UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/18 "2018-02-16T19:12:12Z")

</div>

Don't reply and change the subject to something unrelated. I didn't see this  
till now due to it.

sip.allstarlink.org has been gone for close to a year since DNS migrated.

> **···**
>
> On 2/15/18 5:44 PM, K5CG wrote:
> 
> > It appears that sip.allstarlink.org is no longer a valid DNS hostname. I am  
> > able to SIP connect using the .178 IP address.
> 
> --  
> Bryan Fields
> 
> 727-409-1194 - Voice  
> [http://bryanfields.net](http://bryanfields.net)

---

<div class="post-metadata">

### Author: ![K5cg](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/k/8797f3/32.png) [@K5cg](https://community.allstarlink.org/u/K5cg)
#### Post date: [February 17, 2018, 1:30am UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/19 "2018-02-17T01:30:52Z")

</div>

Hi Brian,

I was expecting the new subject line to start a new topic but it didn’t. Apologies.

So the support page isn’t current.

> **···**
>
> 73
> 
> Danny
> 
> K5CG
> 
> * * *
> 
> > **From:** “Bryan Fields” [Bryan@bryanfields.net](mailto:Bryan@bryanfields.net)  
> > **To:** “Users of Asterisk app\_rpt” [app\_rpt-users@lists.allstarlink.org](mailto:app_rpt-users@lists.allstarlink.org)  
> > **Sent:** Friday, February 16, 2018 1:12:12 PM  
> > **Subject:** Re: [App\_rpt-users] [sip.allstarlink.org](http://sip.allstarlink.org) A record
> 
> > On 2/15/18 5:44 PM, K5CG wrote:
> > 
> > > It appears that [sip.allstarlink.org](http://sip.allstarlink.org) is no longer a valid DNS hostname. I am  
> > > able to SIP connect using the .178 IP address.
> > 
> > Don’t reply and change the subject to something unrelated. I didn’t see this  
> > till now due to it.
> > 
> > [sip.allstarlink.org](http://sip.allstarlink.org) has been gone for close to a year since DNS migrated.
> > 
> > –  
> > Bryan Fields
> > 
> > 727-409-1194 - Voice  
> > [http://bryanfields.net](http://bryanfields.net)
> > 
> > * * *
> > 
> > App\_rpt-users mailing list  
> > [App\_rpt-users@lists.allstarlink.org](mailto:App_rpt-users@lists.allstarlink.org)  
> > [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users)
> > 
> > To unsubscribe from this list please visit [http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app\_rpt-users](http://lists.allstarlink.org/cgi-bin/mailman/listinfo/app_rpt-users) and scroll down to the bottom of the page. Enter your email address and press the “Unsubscribe or edit options button”  
> > You do not need a password to unsubscribe, you can do it via email confirmation. If you have trouble unsubscribing, please send a message to the list detailing the problem.

---

<div class="post-metadata">

### Author: ![VK7HH](https://community.allstarlink.org/user_avatar/community.allstarlink.org/vk7hh/32/857_2.png) [@VK7HH](https://community.allstarlink.org/u/VK7HH)
#### Post date: [February 22, 2018, 6:11am UTC](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998/20 "2018-02-22T06:11:12Z")

</div>

I've made a YouTube video with clips from a single conversation I had this  
morning on the repeater. The audio was recorded on my dashcam.

As can be heard in the video, when I start the conversation, the audio  
delay is nil, or very little when unkeying. However, by the time I'm  
finished (I think the conversation lasted about 20 minutes) the audio delay  
is out to 4 or 5 words!

We were both using the same repeater. We have a repeater linked in from  
another location. I've noticed when talking to someone via that method, the  
audio delay issue does not build up so quickly.

Hopefully this explains a bit better the issue I'm having.

Regards  
Hayden VK7HH

[Next page](https://community.allstarlink.org/t/simulcast-buffer-value-issue/13998.md?page=2)
