MTR2000 Interfacing issue

[/\/\y 2 cents]

Folks,

Got a guy trying to interface to the MTR2000 UHF and on the 96 pin connector it would seem the mic audio pin is stripped of PL when audio is fed into it (brilliant).

So I told him to go into the service microphone port on the front.

No dice. Got PTT, RX audio, no TX audio. Bought a NEW PALM MIC and shucked it open like an oyster and soldered right into the MIC line. No audio.

Put a HARRIS butt set on the wire coming out of the remote accessory that hands off into the mic line, and CAN hear the audio BEAUTIFUL so its not the non-Moto accessory.

600ohm basic stuff right?

What is going on with this station? Is there some secret I do not know? Is there an impedance issue? Loading issue?

HELP! My flight is leaving and I need to get some TX audio on this MTR clunker thing ASAP.

Thanks to all labbers. The one who helps me get it going and not miss my flight will win a prize with a $400 street value (price of my ticket.)

Regards,

KJ4MDZ

[Batwings21]

Check this in rss,

External PTT Mapping


The External PTT Mapping drop down box allows the user to define the functionality for the external PTT
signal.

The drop-down list selections are:

None; the external PTT signal is disabled
Microphone; key the station and transmit the microphone audio
Wireline; key the station and transmit the wireline audio
Repeater; key the station and transmit the receiver audio
Aux. Audio; key the station and transmit the auxiliary audio
NOTE: A TX PL signal defined on the Channel Encoder window is not
transmitted together with the auxiliary audio !
Aux. Audio & Wireline; key the station and transmit the auxiliary audio mixed with the wireline
audio.
NOTE: A TX PL signal defined on the Channel Encoder window is not
transmitted together with the auxiliary audio !

You should be able to set it to wireline and input the audio on the rear line in connector.

[Batwings21]

And go back to using the 96 pin external ptt

[Jim202]

Not that this might be the problem with no TX audio from the mic connector, but remember that
there is a bias voltage on the mic hi line. If what you connect to this point doesn't isolate the DC,
you could in fact ground out any mic audio. I used a cap to go in series with the mic hi line.
Something like a 1 uf will work.

I have been playing with the MTR2000 radios a little and gave up trying to use either the mic jack
on the front or the 96 pin connector on the rear. I have had the same issues of the mic audio
would make it through, but no PL on the transmitter. In another software configuration I could
get the PL on the transmit carrier, but no TX audio.

My solution was to go to the tone remote control that is default for the radio. Just remember that
you have to program the function tone for each of the RF channels and set the other selection for
I think it was LLGT on keying. Maybe wrong in that statement, but there was another window
that you had to set for every channel.

At least using the tone remote, I could change channels and have TX audio with PL or DPL.

Jim

Folks,

Got a guy trying to interface to the MTR2000 UHF and on the 96 pin connector it would seem the mic audio pin is stripped of PL when audio is fed into it (brilliant).

So I told him to go into the service microphone port on the front.

No dice. Got PTT, RX audio, no TX audio. Bought a NEW PALM MIC and shucked it open like an oyster and soldered right into the MIC line. No audio.

Put a HARRIS butt set on the wire coming out of the remote accessory that hands off into the mic line, and CAN hear the audio BEAUTIFUL so its not the non-Moto accessory.

600ohm basic stuff right?

What is going on with this station? Is there some secret I do not know? Is there an impedance issue? Loading issue?

HELP! My flight is leaving and I need to get some TX audio on this MTR clunker thing ASAP.

Thanks to all labbers. The one who helps me get it going and not miss my flight will win a prize with a $400 street value (price of my ticket.)

Regards,

KJ4MDZ

[thebigphish]

Use the pins on the J5 systems connectors for TX Ext PTT & COR (b21 & c10), ground the - sides of the 4wire wireline, and feed the respective audio & RX out of the Line 1 + & Line 2 + wireline feeds. Map ext Ptt in the RSS to "same as wireline" and voila! you get PL on TX, clean audio, and 4 wires to set up.
PM me with details, i just learned ALL ABOUT these!

I wouldn't recommend going thru the local mic for TX audio, stick to the backplane, it'll get ya there!

[RKG]

Zetron makes a neat attachment for the MTR2000. It plugs into the 96-pin connector and gives you screw terminals for the functions normally associated with an external controller. It also give you the ability to mix external audio and external PL/DPL. Under $100, as I recall.

[Batwings21]

So did you get it going?