Motorola HT1250 XPand Technology?

[Java]

3 Simple Questions
Who has it?
Was is it?
What does it do?

[Wiregeek]

Everyone has it. It's fiddlin' with the audio. It does audio things.

Please see http://batboard.batlabs.com/viewtopic.php?t=18982 for more information, and the terms "Audio Emphasis" "Audio Expansion" "Audio Compression" should prove fruitful research starters.

This is... not a simple thing in execution or description, but the above thread has quite a bit of information and historical knowledge in it.

[Java]

Everyone has it. It's fiddlin' with the audio. It does audio things.

Please see http://batboard.batlabs.com/viewtopic.php?t=18982 for more information, and the terms "Audio Emphasis" "Audio Expansion" "Audio Compression" should prove fruitful research starters.

This is... not a simple thing in execution or description, but the above thread has quite a bit of information and historical knowledge in it.

gr8, thanks

[Satelite]

Hello:
This wont be an exact description but it will give the basic info why they did it and what its function was for.
Motorola first as I recall anyway came out with EXPAND in the M1225 mobile and 1225 portable.
It took the audio and compressed it into a smaller packet and txd it to another EXPAND capable radio through the noisy air waves and when received by another expand radio the audio was re expanded back to normal audio again.
Purpose was to be able to transmit a smaller audio packet through extremely noisy air waves thus being smaller in size it wouldn't absorb much of the noise in tx mode to another radio and when received by another radio the audio packet was then re expanded back to normal size and any extra white noise trash was also expanded but in the process of re expanding the audio the white trash noise was actually thinned and spread out to be less of an issue.
In my experience with the EXPAND Technology as Motorola called it I myself didn't care for the returned audio after expand was used so stayed with not using the expand tech myself.
With the Motorola m1225 and p1225 radios you could set by program to either turn on expand or turn it off in the radio.
I left it off as it didn't make much difference in better to me so didn't bother using it.
But I wasn't in a rather nasty noisy situation either and if I was then well that's a different issue now and id be inclined to give it another try then.
As stated above that's not the exact in expands technology but with a hillbilly simple answer and description that's what it was designed to be used as.
Satelite

[Java]

Hello:
This wont be an exact description but it will give the basic info why they did it and what its function was for.
Motorola first as I recall anyway came out with EXPAND in the M1225 mobile and 1225 portable.
It took the audio and compressed it into a smaller packet and txd it to another EXPAND capable radio through the noisy air waves and when received by another expand radio the audio was re expanded back to normal audio again.
Purpose was to be able to transmit a smaller audio packet through extremely noisy air waves thus being smaller in size it wouldn't absorb much of the noise in tx mode to another radio and when received by another radio the audio packet was then re expanded back to normal size and any extra white noise trash was also expanded but in the process of re expanding the audio the white trash noise was actually thinned and spread out to be less of an issue.
In my experience with the EXPAND Technology as Motorola called it I myself didn't care for the returned audio after expand was used so stayed with not using the expand tech myself.
With the Motorola m1225 and p1225 radios you could set by program to either turn on expand or turn it off in the radio.
I left it off as it didn't make much difference in better to me so didn't bother using it.
But I wasn't in a rather nasty noisy situation either and if I was then well that's a different issue now and id be inclined to give it another try then.
As stated above that's not the exact in expands technology but with a hillbilly simple answer and description that's what it was designed to be used as.
Satelite

Great little story, I like reading replies like this! Thanks

[Satelite]

Hello Java
I hear ya there on like these better described infos.
Too bad you weren't around during the Monty Scisco days - as Batlabs back then was BATLABS instead of todays batlabs.
The bds been quite a bit un useful in the present days atmosphere .
But it is what it is.
Satelite

[d119]

Actually, what it is, is companding. Has nothing to do with "packets" or anything like that. Referring to "packets" implies that the transmissions are somehow digital, which they are not.

It's Motorola's proprietary term for audio companding. They referred to it as "HearClear" on the 900MHz band.

For accurate information, take a look at https://en.wikipedia.org/wiki/Companding

[Satelite]

Hello
And im aware the audios not an actual packet .
It was stated in my reply that it wasn't exactly the way it happened but as I said in hillbilly explanation it was the simplest way to get him to understand it better.
And ill bet you he did finaly understand much better what its purpose was and for after reading it.
Expand / Compandering / Hear clear doesn't matter pretty much same principal.
Explanation as explained wasn't to be gospel and if you read my reply youd know that.
If you take packet out and say txd smaller bandwidth he may or may not know the term bandwidth as it applies to audio and still be confused so I did use packet as a describing word but did leave digital out as I knew we were talking analog here and again I wasn't out to confuse him any further than he was.
Oh well at least he now knows the answers to what he wanted to know.
Satelite

[Bill_G]

... and all of the effort to massage the audio was meant to overcome the non-existent problem of reduced S/N equating loss of range (which is a whole other non-existent bag of worms IMO).

[Java]

I tried companding on a UHF repeater and those of us who use XTS and XTL said the audio was SUPER Bassey. It seems the best option is turning De And pre Emphasis on, AGC on for Expansion type. I tried disabling Compression and Expansion and running just Pre emphasis, it Yielded super base audio again. Of course I am centuries late experimenting with a radio that is considered to some OLD. I understand it is NOT packets, as that would indicate some sort of digital transmission.
I usually only play with the Astro & Astro25 stuff but I have had my eyes on the HT series for a very long time couldn't justify the price.

OffTopic
next is jamming a Model 3 HT1250 codeplug into a HT750, I want a VHF model 3 without the $250 price.
did these HT1250s come in with IS housings? I pulled apart this old R split and it has a IS sticker inside below the RF deck. Housing was the type where Motorola was painted on, Purchased one of those prebuilt ht1250 housing for $40 and it feels like chinese sh!t, wonder when china will start cheaping out XTS,APX etc *Thumbsdwn Wish there was someone with some REAL model 3 housings.

[Bill_G]

Just leave it plain old FM with pre-de emphasis enabled. That's as good as it gets. Turn all the companding off in everything. Then any model radio will sound about the same.