Batboard

Hi all!

I want to make my Waris Mobiles (CDM1250, CDM1550, GM160 & GM360) absolutely silent when it turned on and in receive signals.

I have changed Minimum Radio Volume (CPS: Per Radio / Alerts / Volume) to "0". Radio began to sound more silently, but nevertheless it is not absolutely silent even when volume rotary knob in CCW position.

Yes, It speak in a low voice, but at night - when all sleep - it nevertheless disturbs.

Any ideas (excluding built-in speaker disconnection)?

The only way you're going to completely silence it is to remove the control head, remove the volume/microphone board from the head, jumper R9001(the only fixed resistor on the board), and then reassemble everything. R9001 is a 10 ohm resistor between the low side of the volume control and ground.

Ok, thank you!

But it's not my solution :)

It's pity that no software based method available :(

Handset Audio
If handset audio is enabled, the radio’s speaker will be muted if the handset is lifted “Off hook”.

Checked on GM340 UHF1:
Per Personality-Tx/Rx-Auto Reset Mode - Disabled;
Per Radio-Miscellaneous-Global-Handset Audio - Selected;
Per Radio-RF-Rx-Hook Type - Permanent.
You must use hook plate on microphone to select mute/unmute.
Accessory connector don't work propely.

But, may be simply turn off radio?

Sergio MD wrote:Accessory connector don't work propely.

What you mean? That Accessory connector will not work property after that?

I need fully functional Accessory connector, because I use few buses, like is: Flat TX Audio Input, Flat RX Audio, SQL Status and PTT In.

But, may be simply turn off radio?

Impossible. Radio must be turned ON and in receive signals.

Correction:
Accessory connector don't work propely as hook switch.

The best way to mute GM360 is as follows (example):
Per Radio-GP I/O Lines-Pin#12 - Mute Audio PA - Active - Low.
Short this pin to ground or control it by switch to mute radio.
Or:
Add new channel as clone of your working channel, set
Per Channel#X-Miscelleneous-Per Channel Output - Selected;
Per Radio-GP I/O Lines-Pin#4 - Per Channel Output - Active - Low.
Short pins #12 and #4 and radio will muted on channel X.

Al wrote:The only way you're going to completely silence it is to remove the control head, remove the volume/microphone board from the head, jumper R9001(the only fixed resistor on the board), and then reassemble everything. R9001 is a 10 ohm resistor between the low side of the volume control and ground.

Where you found such resistor as R9001? I have checked few SMs (GM300 Series, CDM1550 SM & etc.), but no such resistor as R9001.

But only one 10 ohm resistor exist in Waris Mobile Control Head - this is R0813. But it's not part of Radio Volume circuit (it's in MIC circuit).

Any ideas?

Wow! You are a very patient man if you're working on this problem for over a year. Why not put a toggle switch in line?

Bill_G wrote:Wow! You are a very patient man if you're working on this problem for over a year. Why not put a toggle switch in line?

I don't like to modify radios in hardware. Removing resistor, hacking EEPROM/FLASH is ok. But not a making wires outside or holes in case.

What are you doing with the radio that it needs to be on all the time, & silent but can't have the spkr disconnected?

Bill_G wrote:What are you doing with the radio that it needs to be on all the time, & silent but can't have the spkr disconnected?

Recording.

You've gone through the schematic and can't find an appropriate point to more fully mute the radio without affecting the det audio output to your logging recorder? Does your recorder have an adjustable live monitor output?

Bill_G wrote:You've gone through the schematic and can't find an appropriate point to more fully mute the radio without affecting the det audio output to your logging recorder? Does your recorder have an adjustable live monitor output?

I do not want to mute radio forever. Sometimes I need to listen audio from built-in speaker. I just want to make Volume knob works from true 0 level. Not from 10% or something else. If you able help with it, please help.

Well, that doesn't sound right. 10% audio from an unmodified radio seems impossible. Even if R9001 10 ohm resistor were present on the vol ctrl brd, it would be looking into a 4.7k & 1.5k resistor bridge. That should be effectively zero. I would verify R9001 was present. Then I would look for mods and possibly corrosion in the mic jack and vol brd, then on the logic brd.


You can get a full GM300 manual at Repeater Builder -

http://www.repeater-builder.com/maxtrac ... index.html

Bill_G wrote:Well, that doesn't sound right. 10% audio from an unmodified radio seems impossible. Even if R9001 10 ohm resistor were present on the vol ctrl brd, it would be looking into a 4.7k & 1.5k resistor bridge. That should be effectively zero. I would verify R9001 was present. Then I would look for mods and possibly corrosion in the mic jack and vol brd, then on the logic brd.

You can get a full GM300 manual at Repeater Builder -

Bill, my question about Motorola Waris Mobile (CDM1250, CDM1550 & etc.) /GM300 Professional Series.

GM300 Professional Series - this is Waris Mobile radios for EMEA (Europe, Middle East, Africa) market. GM300 Professional Series includes GM140, GM160, GM340, GM360, GM380, GM640, GM660 & GM1280 radios, but does NOT include old Motorola Radius GM300 transceiver.

Please look attentively to first post and subject.

Sorry pal. I wasn't aware they called the CDM series GM300. Kinda confusing. Carry on.

god bless the appliance users.

Bill_G wrote:Sorry pal. I wasn't aware they called the CDM series GM300. Kinda confusing. Carry on.

Yea, Motorola has tangled people when called in EMEA Waris radios as G*300 Professional Series.

I know the problem you're talking about now. Experienced it myself. The volume indeed does not turn down all the way. Imagine a back room of equipment with a rack of twelve CDM mobiles just barely babbling during shift change as crews call in their warrants. You're suddenly grateful for all the server fans buzzing. There is no software fix for it. I'll look at the service manuals this week to see what hardware fix can be applied. I'm betting there is a resistor like R9001 in the CDM series that keeps the pot above ground.

Well pooper scoopers. The min vol cannot be set to zero in tuner or cps. 100% digital audio proc. The vol pot just sends variable 5v to the ctrl hd uP which puts in on the spi bus and over to the prog atten in the asfic on the main brd. Theoretically possible but not practically attainable. I can see a point in the schematic to change the gain of a driver stage. I can also see a point where you could keep the mute gate applied full time. Both require physical mod to the radio. I'm thinking your best choice is to disassemble the head, pull the spkr plug, reassemble the head, and then install an external spkr with an L pad or a switch. Not as pretty as a soft solution, but the only one available right now.

Ok, thank you very much for your research!

You are welcome. My pleasure.

You can always run a fan.