Odd Hum with XTS3000

[MattSR]

Hi guys,

I have come across a strange problem with my XTS3000. I have three batteries, one aftermarket, and two genuine /\/\ batts. The radio has been taken out of band (up to 475 or so) and whenever I Tx using the motorola batteries, theres a loud AC hum.

When I tx down on 430Mhz the hum is still just there but not as noticeable. When I use the aftermarket battery, the hum is gone!!!!

Does anyone know where I should start looking?

Cheers,
Matt

[cbus]

Hi guys,

I have come across a strange problem with my XTS3000. I have three batteries, one aftermarket, and two genuine /\/\ batts. The radio has been taken out of band (up to 475 or so) and whenever I Tx using the motorola batteries, theres a loud AC hum.

When I tx down on 430Mhz the hum is still just there but not as noticeable. When I use the aftermarket battery, the hum is gone!!!!

Does anyone know where I should start looking?

Cheers,
Matt

dunno, but what is the date code on the battery matt ??

If it was me ide just throw the batterys making the hum in the bin

if you want to test another genuine mot battery, you can borrow one of mine

[MattSR]

Sweet, thanks for that tracka - I have done a bit more testing and its only happening on the out of band frequencies (477mhz on a R band radio)

The batts hold good charge so im reluctant to chuck them.. maybe I can use them for Rx/HAM use only for something

Cheers,
Matt

[MattSR]

Hmmm this gets better and better

When I Tx on the out of band freqs, it beeps and flashes the low battery icon/LED but when I switch to an in band freq, the indicators go away!?!?!?!

Truly stymied,
Matt

[cbus]

Hmmm this gets better and better

When I Tx on the out of band freqs, it beeps and flashes the low battery icon/LED but when I switch to an in band freq, the indicators go away!?!?!?!

Truly stymied,
Matt

you sure that the VCO is just not locking itself out ??

remember 7mhz is a bit of a difference if the radio is tuned to a lower frequency say 454mhz ??

or, the battery is rooted!. the reason it might be cutting out out of band is because the radio is drawing more power seen its out of its efficiency range and the battery is shitting itself ??

i'll loan you a regular mot battery no probs. see if it does it with that.

Ill chat on msn or pm.

Cheers

[amds]

There's a known firmware problem that causes humming upon transmit at certain voltage levels. Are you running something like R05.60.00?

What do IMBE transmissions sound lke? Can you hear a "chop chop chop chop chop chop" noise in the background, when receiving the transmission from the problematic radio, on another radio? This is a firmware issue that's corrected in DSP7. It sounds like a helicopter noise.

[MattSR]

Hi amds,

According to service mode the radio is DSP 8.02.06 The host level is 7.something

I'll have to get a receive radio and check what it sounds like on IMBE receieve

Thanks for the tips,
Matt

[MattSR]

Just did some more testing, and yes, it only happens at certain voltage levels.

[MattSR]

I replaced the housing on my XTS with a brand new one (thanks AJ) and the hum has gone.

On closer inspection, the flex in the housing had been damaged which was creating a bad earth somewhere.....

Cheers,
Matt

[DES-AJ]

Glad to of been of help Matt

Cheers,
AJ