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KA5PIU
02-15-2011, 02:25 PM
Hello.

Now that they have merged,,,,.:-D
I have assembled several P-25 adapters, both for receivers as well as transceivers.
This is always the TI chipset, retasked for this service.
Several have said that this is not an option as the chipset is too expensive.
There was also question as to how I was able to get samples.
The answer to both questions is simple, XM.
Yes, the satellite service, XM, uses the AMBE codec.
I was very easily able to get a sample chipset by asking someone who was producing RF designs.
Since there are license issues I have never offered the basic design, but it is a very simple matter to reverse engineer this.
This was placed on demonstration at the hamfest in Temple as well as San Antonio.
It was designed and built for the purpose of allowing members of CAP to adapt member owned radios to P-25 and for no other use.
Look at how XM works, they actually use a dual mode AMBE chipset, it can easily be reconfigured for full duplex operation.
And, data rate is set dynamically, it is a software instruction.
Due to the fact that some ham had called up DVSI and had said all sorts of chit, around the time I was in "negotiations" with Motorola, I make it a point to pretty much stay very clean in this matter.
But, extract the data and audio chain and configure the chip, feed it P-25, and see what you find. 8)

N2CHX
02-15-2011, 02:38 PM
Pics or it didn't happen.

Never mind, it just didn't happen.

NQ6U
02-15-2011, 02:40 PM
WART

kd8dey
02-15-2011, 02:50 PM
WART

http://www.compoundw.com/en/Products.aspx

WA4TM
02-15-2011, 05:55 PM
Would that be a genital WART????:stirpot: :dance: :wtf:


WART

W3WN
02-16-2011, 10:52 AM
Would that be a genital WART????:stirpot: :dance: :wtf:Are you saying that... never mind.

I'm not entirely sure what merger ku goniff is talking about... and I'm sure he'll enlighten us soon enough... but I did find this reference: http://wiki.multimedia.cx/index.php?title=AMBE

I do find it interesting that the digital voice codec that D-STAR is using may also be the one XM is. If that is true, pending independant verification of course, then the complaints about D-STAR being so proprietary may have lost a leg to stand on. May.

KC2UGV
02-16-2011, 11:11 AM
The argument isn't how expensive the AMBE2020 chip is. I mean, the chip is like $0.20-$0.75 depending on how many you get at once. The argument against AMBE2020 are:

* Single-sourced supplier. Should the one supplier go under, no more AMBE2020. Should TI break it's relationship, no guarantee the new chip will be drop-in replaceable.
* Inability to implement in software. With AMBE202, you can NEVER write a vocoder plugin to ANY system. So, no soft-only solutions.
* Inability to expand the vocoder, and improve on it for amateur needs.

KC2UGV
02-16-2011, 11:12 AM
Are you saying that... never mind.

I'm not entirely sure what merger ku goniff is talking about... and I'm sure he'll enlighten us soon enough... but I did find this reference: http://wiki.multimedia.cx/index.php?title=AMBE

I do find it interesting that the digital voice codec that D-STAR is using may also be the one XM is. If that is true, pending independant verification of course, then the complaints about D-STAR being so proprietary may have lost a leg to stand on. May.

No, it still has the leg.

Show me an AMBE2020 vocoder I can use in Asterix.

Or, easier still: Show me the code to AMBE2020.

NQ6U
02-16-2011, 11:15 AM
The argument isn't how expensive the AMBE2020 chip is. I mean, the chip is like $0.20-$0.75 depending on how many you get at once. The argument against AMBE2020 are:

* Single-sourced supplier. Should the one supplier go under, no more AMBE2020. Should TI break it's relationship, no guarantee the new chip will be drop-in replaceable.
* Inability to implement in software. With AMBE202, you can NEVER write a vocoder plugin to ANY system. So, no soft-only solutions.
* Inability to expand the vocoder, and improve on it for amateur needs.

Exactly. It's a proprietary codec, no one else can implement it either in software or hardware. That's the issue many hams (including myself) have with D-Star.

KA5PIU
02-17-2011, 11:31 PM
Exactly. It's a proprietary codec, no one else can implement it either in software or hardware. That's the issue many hams (including myself) have with D-Star.

Hello.

Nail on the head!
First off, YES! AMBE is AMBE, TI does very little to customize the chip.
The early Sony units have the TI branded chips! just take a look.
Look up the TI application notes for the chip.
Now, pull the covers on the earlier M/A-Com talkies that do pro-voice, IMBE, but the chips sourced can to both.
There is but a few digits difference between the 2 chips.
And, no pictures hoopla, you can get your butt down to Texas and look at the thing.
In Dallas, Tanner Electronics on Valwood Parkway.
When I was in Dallas I was told that one machine was "closed" so I went to another and several hams were playing with the thing.
One went home and got a P-25 compliant scanner so to prove or dis-prove, it passed the test.
Houston, Electronics Parts Outlet on Fondren, the owners saw this And made a video of it.
The trouble with pictures, as was with the revolver, is that there is no end to it.
If it is connected to a talkie and P-25 is tuned, and it works, that is the gold standard in proof.
That is my position.

KC2UGV
02-18-2011, 09:11 AM
Hello.

Nail on the head!
First off, YES! AMBE is AMBE, TI does very little to customize the chip.
The early Sony units have the TI branded chips! just take a look.
Look up the TI application notes for the chip.
Now, pull the covers on the earlier M/A-Com talkies that do pro-voice, IMBE, but the chips sourced can to both.
There is but a few digits difference between the 2 chips.
And, no pictures hoopla, you can get your butt down to Texas and look at the thing.
In Dallas, Tanner Electronics on Valwood Parkway.
When I was in Dallas I was told that one machine was "closed" so I went to another and several hams were playing with the thing.
One went home and got a P-25 compliant scanner so to prove or dis-prove, it passed the test.
Houston, Electronics Parts Outlet on Fondren, the owners saw this And made a video of it.
The trouble with pictures, as was with the revolver, is that there is no end to it.
If it is connected to a talkie and P-25 is tuned, and it works, that is the gold standard in proof.
That is my position.

Rudy, the TI chip is just a PROM with the read fuses blown.

KA5PIU
02-18-2011, 11:22 AM
Hello.

A PROM that acts as a VOCODER?
First off, there is nothing blown, I can read the firmware and manipulate it and write to the chip, the evaluation kit makes that super easy.
Second, the configuration field is only 2k, and is static memory, not a PROM.
This is a hardware solution, a custom chip and not a software solution.
You can buy the development kit as well as others from TI or DVSI.
https://estore.ti.com/
http://www.dvsinc.com/

KC2UGV
02-18-2011, 11:34 AM
Hello.

A PROM that acts as a VOCODER?
First off, there is nothing blown, I can read the firmware and manipulate it and write to the chip, the evaluation kit makes that super easy.
Second, the configuration field is only 2k, and is static memory, not a PROM.
This is a hardware solution, a custom chip and not a software solution.
You can buy the development kit as well as others from TI or DVSI.
https://estore.ti.com/
http://www.dvsinc.com/

Yes Rudy. A PROM which acts as a vocoder.

Yes Rudy, A PROM with the read fuses blown. You can not read the source code off the chip.

KA5PIU
02-18-2011, 05:30 PM
Hello.

First off, what does this have to do with anything?
I do not need to have access to the source code to make the TI chip work, it is clock in, audio in, audio out, data in, data out.
And, this is not open source, nor is the Windows platform, yet this does not stop people from using windows.
To add to this, the source code does not reside on the chip, only the executables.
There are a total of 5 executables running on that chip and they are die fab loaded, there is no PROM involved.
The chip can be updated, at that point the executables can be viewed.
A chip without the DVSI firmware has only the IPL.
The evaluation kit comes with all of this.
But, from my standpoint it is all academic, I am taking a pair of chips out of one product to create another device.
I have no desire to do anything else but do P-25 and ProVoice from the TI chipset.
The people at DVSI had concerns over what I was doing at one point, until I showed them what I was doing.
Some ham ranted on and talked all kinds of chit about me, while the Motorola thing was going on.
Now I simply do not deal with anything that might be questionable.
Taking a chip from one device to use in another is 100% legal, nobody has an issue about that.
That is where I leave it.

N2CHX
02-18-2011, 06:22 PM
Pics or it didn't happen.

NQ6U
02-18-2011, 06:58 PM
Pics or it didn't happen.

Pics and it still didn't happen.

KE7DKN
02-18-2011, 07:46 PM
Hello.

First off, what does this have to do with anything?
[snip]

Hah! Take a guess how often that question applies to your own posts.

N2CHX
02-18-2011, 07:47 PM
Hah! Take a guess how often that question applies to your own posts.

This is the song that never ends, yes it goes on and on my friends. Some people started singing it not knowing what it was........

KC2UGV
02-18-2011, 09:55 PM
Hello.

First off, what does this have to do with anything?
I do not need to have access to the source code to make the TI chip work, it is clock in, audio in, audio out, data in, data out.
And, this is not open source, nor is the Windows platform, yet this does not stop people from using windows.
To add to this, the source code does not reside on the chip, only the executables.
There are a total of 5 executables running on that chip and they are die fab loaded, there is no PROM involved.
The chip can be updated, at that point the executables can be viewed.
A chip without the DVSI firmware has only the IPL.
The evaluation kit comes with all of this.
But, from my standpoint it is all academic, I am taking a pair of chips out of one product to create another device.
I have no desire to do anything else but do P-25 and ProVoice from the TI chipset.
The people at DVSI had concerns over what I was doing at one point, until I showed them what I was doing.
Some ham ranted on and talked all kinds of chit about me, while the Motorola thing was going on.
Now I simply do not deal with anything that might be questionable.
Taking a chip from one device to use in another is 100% legal, nobody has an issue about that.
That is where I leave it.

Hello.

Sure.
Uh-huh.

NQ6U
02-18-2011, 10:29 PM
just a PROM with the read fuses blown.

For a minute there, I thought you were talking about Rudy.