Senheiser headheld radio mike

[lonfire]

hi,

I have got a senheiser handheld (sorry typo in the title!) mic with is it the em300 receiver (not the new G2 model).. it has worked fine for well over a year now.. gets occasional use.. I have noticed that its started making funny noises when its being used.. not all the time..

 

what it did this sunday when I used it was everything the person spoke you got this low frequency hum through it.. when they stopped speaking the hum also stopped.. its not easily reproduceable either.. I tried after the event and couldn't get it todo it.. and sometimes it sort of fades in hum/crackle type noise then it goes..

 

could this be the location of the receiver? I have two receivers in a 4u wood rack.. with a 2u metal case bellow them that has two XLRs for the output and a 4 way extension on the back for the transformers.. the rack is left with its back on and sat on that.. so the two receivers screens point upwards (the rack is at the front of the hall to make sure we don't get dropout)..

 

any thoughts.. the ariels might have been near the transformers.. would this have made the difference? seems strange it comes and goes.. but is really anoying! and we put a new battery in the mic before it was used..

 

 

thanks

chris

[Djbarryblue]

Hi,

 

We had a similar thing a few weeks ago with a 500 serious G2 and the same after the show could we buggery get it to make the noise again. We have got 17 lapels and 4 hand helds mixture of 500's and 500 G2 s and never heard it before. Hmmm bizar!!!

 

Thanks

Barry

[Lamplighter]

This sounds like a typical RF problem, either another source on the same channel or a mix between channels. It is likely, if a mix, to result in a beat at the oscillator frequency or even one of the receiver IF's. It is not unusual to get such a problem that is only apparent when the wanted channel is modulated. If it is an on channel problem the most common causes are computers or faulty lights( usually modern high efficiency types) though I have come across such diverse sources as LEDs in telephones to faulty rectifiers in various forms of power supply.

 

It would be useful to know which band was affected and how many channels.

 

Brian

[Pete McCrea]

We've just had a ew100 back from Sennheiser with a replaced rf board.... They have been suffering from rf drop out and occasional cracks and pops.

[benge]

I had the same problem, but on an AKG system..... found that it was the battery...

 

Ben

[paulears]

I'd go with Lamlighters solution. RF issues. Intermod does cause some wierd and wonderful problems that never happen again with different user locations. Check that someone else with an operating transmitter didn't stand next to the receivers at the problem moment. Mixing products are very diifficult to reproduce afterwards.

[lonfire]

hi guys,

I will have a look at what frequency it was set on.. the only other transmitter WE use is a senheiser instrument pack for a guitar.. but that wasn't switched on at the time..

 

the ariels from the receievers are in the normal place on the back of them, but are near the transformers for the units.. recon this could have caused the problem? I have moved the ariels arond the other way in the case to see if this helps..

 

thanks

chris

[ben.suffolk]

The only time I have had anything similar to this is when I had an IEM on the same freq as the mic. I would have expected as the IEM TX was next to the mic RX that I would have just had IEM and no sound at all from the mic (Both Sennheiser ew300)

 

But I was just getting a somewhat distorted vocal. It wasn't till the other performer with the IEM said she was only getting the other persons voice really loud that I twigged, what I had done. I could have sworn the IEM had been on a different freq :)

 

Ben