WRVZ490

[WRVZ490]

Hey guys. I’m a bit of a newbie with GMRS. Hopefully y’all can help me out here. I have a Btech GMRS-V2 as well as an older Baofeng UV-5R. Recently I have been having an issue while receiving transmissions. When receiving either on GMRS channels or scanning local dispatches the transmission will pulse in and out. Sometimes it will even do it when no one is transmitting (at least that I can hear).Happens on both radios. I do have a Nagoya NMO-200C magnetic mounted antenna that is new. Didn’t start doing the pulse thing till after I got it. But now I’ve noticed that it still does it sometimes when not connected to it and using the antenna that comes with the radios. Thoughts?

[marcspaz]

Are you using both of them in a mobile application, as base radios, or both?

[WRVZ490]

As mobiles for the time being till I get an actual mobile. Mostly just the Btech. Only broke out the Baofeng just to have as a spare and to compare. 

[WRQC527]

1 hour ago, WRVZ490 said:

When receiving either on GMRS channels or scanning local dispatches the transmission will pulse in and out.

I've had two radios that act in a similar manner. The first one was a Wouxun KG-UV9T handheld, the other is a Juentai JT-6188 mobile. Both of them are virtually unuseable as mobile radios in my 1998 Sienna because some signal generated by the vehicle is breaking the squelch randomly. My guess is since it only happens when the van is moving, it has something to do with the ABS or vehicle speed sensor circuits. In any case, the squelch circuits in those two radios are unable to deal with the signal, whereas with my Yaesu mobiles and handhelds, I have no such problems. Another thing is that squelch settings on the Baofeng radios are not as effective as they are on, say, Yaesu radios. I have 2 UV-82s, and in order to set up decent useable squelch settings, I used Chirp and went into the service settings and adjusted them there. I don't know if the same settings option exists for the GMRS-V2 or the UV-5R. With the JT-6188, the squelch settings are useless. Zero is wide open, 1-9 are all the same. I'd bet $100 in Monopoly money that you're having the same issue I had.

[marcspaz]

If you are mobile, actively in motion and hearing pulsating while receiving a signal, there is a very good chance you are simply hearing what is known as picket fencing.  As we travel, especially in cities and wooded areas, 'things' between you and the station you are hearing actually cause a shadow, causing a pulsing of the received signal. 

It is especially common with handheld radios while using an external antenna.  When you transmit, people on the other end will also hear your transmitted signal pulse, as well.