MT1000 16ch VHF.........Problem
Moderator: Queue Moderator
I have a customer who has brought in a VHF, 16 channel, MT1000. This radio has been working fine up until recently. The radio will power up, recieve, scan, etc... everything seems to be working except when you try to transmit. When the radio is keyed, it turns off. You get the power on tone , just like you turned the switch off and back on. At no time does the TX red light come on. The battery is brand new, and fully charged. Radio has also been tested with other batterys to eliminate this possibility. All of the programming has been reviewed and is in good order. Has any one ran across this one before? Any suggestions other than using it as a paperweight????
Hi:
1st, when the radio is TURNED ON, do you
get a good " Beep" tone?
If so, chances are pretty high that the
radio may be programmed incorrectly. I know
you indicated all the rss is OK, but a problem similar to what you described could
be due to the channel being programmed as
" Receive " only.
Also, after a period of time ( years ) the
ON/OFF VC control does go bad and has a impact on transmitt performance.
If you have a Test fixture and can measure the TX output power, you will see what I am
speaking of.
The MT1000 has a capability of delivering
a easy 5-6 Watts of output power, and the
contacts accross the VC control sometimes
do get pitted causing poor tx performance.
Also, if the " Incorrect" range is chosen,
then the VCO will not lock, and you will hear
that inop tone. The range of the radio is stampped on the VCO Block on main housing.
Sometimes you may have to remove the Controller to look at it. USE CAUTION
if you decided to do this as one can damage
the connectors if you are not carfull.
Its also advisiable to make sure all the
Battery Contacts are either new, or very
clean, along with a good battery.
Sometimes ( pretty rare ) I have seen these radios corrupted by a pentium class computer,
so you would be advised to use a 386-486-25 Series computer if you desire to be safe.
Use of other faster computers is like rolling dice at a casino....You may get
lucky, but eventually you will loose.
Anyhow, I do buy radios that are paper
weights if you should give up on the one
you are working on
Monty
1st, when the radio is TURNED ON, do you
get a good " Beep" tone?
If so, chances are pretty high that the
radio may be programmed incorrectly. I know
you indicated all the rss is OK, but a problem similar to what you described could
be due to the channel being programmed as
" Receive " only.
Also, after a period of time ( years ) the
ON/OFF VC control does go bad and has a impact on transmitt performance.
If you have a Test fixture and can measure the TX output power, you will see what I am
speaking of.
The MT1000 has a capability of delivering
a easy 5-6 Watts of output power, and the
contacts accross the VC control sometimes
do get pitted causing poor tx performance.
Also, if the " Incorrect" range is chosen,
then the VCO will not lock, and you will hear
that inop tone. The range of the radio is stampped on the VCO Block on main housing.
Sometimes you may have to remove the Controller to look at it. USE CAUTION
if you decided to do this as one can damage
the connectors if you are not carfull.
Its also advisiable to make sure all the
Battery Contacts are either new, or very
clean, along with a good battery.
Sometimes ( pretty rare ) I have seen these radios corrupted by a pentium class computer,
so you would be advised to use a 386-486-25 Series computer if you desire to be safe.
Use of other faster computers is like rolling dice at a casino....You may get
lucky, but eventually you will loose.
Anyhow, I do buy radios that are paper
weights if you should give up on the one
you are working on
Monty
-
raymond345
- Posts: 268
- Joined: Sat Sep 22, 2001 4:00 pm
Yes I have had the controller do the
same to me .two different times.
These were on the Mt1000 99 ch. VHF
portables.
Raymond eMail [email protected]
same to me .two different times.
These were on the Mt1000 99 ch. VHF
portables.
Raymond eMail [email protected]
This sounds like there is enough available current (amperage) from the battery to make the radio receive, but when loaded with the current required to transmit something is breaking down- in other words, there may be resistance somewhere in the power supply.
It could be anywhere from loose screws on the battery plate, corroced contacts, power switch contacts, connectors.
One you turn off transmit mode, the current requirement drops and the radio's receiver once again gets enough current to operate and gives the "beep."
On a much larger scale, if you have a loose battery terminal on your car, the dome light or parking lights will work normally (receive), but when you try to crank the engine, (transmit) the current requirement goes 20 fold and all goes off. When you release the key, the low current lights (receive) come back on- just like the radio does when you release the transmit button.
Check all connections from the battery inboard- especially those screws on the bottom of the radio. Crank 'em tight!
It could be anywhere from loose screws on the battery plate, corroced contacts, power switch contacts, connectors.
One you turn off transmit mode, the current requirement drops and the radio's receiver once again gets enough current to operate and gives the "beep."
On a much larger scale, if you have a loose battery terminal on your car, the dome light or parking lights will work normally (receive), but when you try to crank the engine, (transmit) the current requirement goes 20 fold and all goes off. When you release the key, the low current lights (receive) come back on- just like the radio does when you release the transmit button.
Check all connections from the battery inboard- especially those screws on the bottom of the radio. Crank 'em tight!