Batboard

Hi,

I have a VHF Visar that beeps as through it had
a low or dead battery even when the battery(s) is fully charged.

The same batteries work fine on my other Visar's.

Would appreciate any help,

Thanks in advance,

Doug

There could be one of two issues with your Visar.

1- Your transmitter, when in use. is drawing to much current from the battery, causing a premature LOW BATT beep. Your PA could be ready to fail.

2- (I am not sure about this one) In the RSS in the service window, somewhere, there is a LOW BATT threshold level that might need adjustment.

Or a third option, there are solder defects under the AFIC or CPU chips, causing a false read on the batt. voltage. Unless you know of a good shop, Motorola flat-rate is in your future.

I second what Tony said. It's a not-uncommon fault with the Visar. Also, there's no 'low battery threshold' adjustment in the regular RSS. I think there is one in LAB.

Todd

Battery treshold adjustment can be done with regular RSS, Eurpean is evn4140. Somewhere under "more options"...

BTW my GP900 doesn't give the chirp low battery signal anymore. When the battery becomes to low it just gives a single tone beep and tje LED flashes red-green

Does some know how I can get the regular chirp back again?

Thanks to all who offered help.

Much appreciated,

Doug

Ruut,

The obvious thing to check is the LOW BATT CHIRP(ENABLE or DISABLE) in the RSS.

motisking wrote:Ruut,

The obvious thing to check is the LOW BATT CHIRP(ENABLE or DISABLE) in the RSS.

Disabling the low battery beep is not a real solution. If there's a problem in the radio where it's giving a pre-mature low battery indication (as is the case with his), it should be rectified to work properly. Otherwise, there's a good chance the radio will fail with a perfectly good battery on it.

On another note, I haven't found a low battery threshold adjustment in the North American RSS, neither the VisarPP, nor the HT1000 RSS. I've never seen the European RSS.

Todd

Todd

The only way the change the threshold in a Visar is by changing a resistor, either R725 or R726. These two form a voltage divider from which the battery voltage is read by the microcomputer at pin J6. Changing these is pointless of course and won’t cure the problem.

As both Tony and Wavetar pointed out, the problem is typically an open connection under the microcomputer. Sometimes you can verify this by applying light finger pressure on the IC while turning the radio on. Re-flowing the joints (all 86 of them) with a proper hot air reflow station cures the problem.
It is likely that other joints under the IC are either open or ready to fail anytime soon as well.

Nand.