Another bleed over issue

[nick1427d]

I have a BC780

Monitoring two FD dispatches

1) 154.325
2) 154.310

both are CSQ on dispatch but I get bleed over on 154.325 from the 154.310. I'm close enough to both that I hear both crystal. I know a beam would help but would like to not go that route. I programmed both at times as FM and NFM but no fix.

Any thoughts

 

[timkilbride]

I have a BC780

Monitoring two FD dispatches

1) 154.325
2) 154.310

both are CSQ on dispatch but I get bleed over on 154.325 from the 154.310. I'm close enough to both that I hear both crystal. I know a beam would help but would like to not go that route. I programmed both at times as FM and NFM but no fix.

Any thoughts

Have you tried the attenuator?

Tim

 

[gewecke]

My suggestion too. It's helped my 780

73,
n9zas

 

[nanZor]

You may want to research this here on RR about Uniden vs RS scanners and the narrow fm filters. I know I've seen it a year or two ago. You may want to look into a high-end rs scanner if these two closely spaced users are super important.

This might be the case that the Uniden does not actually have a true narrowband fm filter bandwidth - just audio compensation. On the other hand, modern high-end radio shack scanners actually switch to a much narrower rf filter bandwidth, but don't compensate for the audio properly. One user said that the RS scanner, while not perfect, allowed for the truly narrowband filtering from an rf standpoint at least.

 

[gewecke]

Nick,
Another trick which may help, besides selective use of the attenuator would be to program all your vhf frequencies in NFM instead of FM.

73,
n9zas

 

[nick1427d]

Here's what I've done so far that "helped" my issue but I'll leave it alone and deal with it

1) Attenuator made the 154.325 scratchy, attenuation on 154.310 isn't going to help my bleed over onto 154.325 so I forgot that option.

2) Since both are fairly strong and only for dispatching I programmed the 154.325 into 154.3255 and it helped with bleed over and still allowed me to pick it up.

Sometimes I go straight here with my questions cause I know they'll be answered!

Thanks for the help

 

[gewecke]

Here's what I've done so far that "helped" my issue but I'll leave it alone and deal with it

1) Attenuator made the 154.325 scratchy, attenuation on 154.310 isn't going to help my bleed over onto 154.325 so I forgot that option.

2) Since both are fairly strong and only for dispatching I programmed the 154.325 into 154.3255 and it helped with bleed over and still allowed me to pick it up.

Sometimes I go straight here with my questions cause I know they'll be answered!

Thanks for the help

Try prog those frequencies in NFM rather than FM. :wink:

73,
n9zas

 

[nanZor]

Try prog those frequencies in NFM rather than FM

Uniden's NFM as I understand it uses the same if filter as FM - it is just an automatic audio compensation for the narrow deviation if you use NFM, although the deemphasis is correct. RS on the other hand has separate IF filters, but only boosts the audio in overall amplitude without the deemphasis. At least, that was what I read from the earlier reports.