Reception depends on exact position?

[bd348]

Got two new Wouxun KG-S88G handhelds.  Super het receivers.  Reception seems to depend heavily on the exact position of the radio.  If I place it HERE then it's great, full-scale reception of the repeater.  If I move it a few inches over to THERE, reception can go to near 0, sometimes not even breaking the squelch (set at 1, where 0 is open).  If I move it around a foot or so further, it may suddenly become great again.  If it stays put where the reception is great, it stays great.  Both radios behave the same, either with the stock antennas or the 15" Nagoya GMRS-tuned antennas.  Two radios, four antennas, all do this.

This testing is being done on the 2nd story of a house with aluminum siding.  Faraday cage with windows, possibly bouncing signals all over the place inside.

Meanwhile, the cheap FRS Midlands receive almost anywhere, and usually better than the Wouxuns.  When one of the new units are placed in a good spot then they best the FRS, but most places the FRS best the superhets.

Handheld transmission does make it into the local-ish repeater and I got a successful radio check, although that was down the street while sitting in the Jeep with fibreglass top, not from inside the house.

In testing between both new radios from across the subdivision, the new radio did hear better than the FRS.  When I went further away to where reception was lost and switched to the mobile unit at 15W, inside the house the FRS received the mobile better than the new Wouxun.  But my wife admitted that the new unit may not have been exactly upright, and the 15" whip was installed at the time.  Angle of antenna?  Perhaps keep the stock antennas for a more wide-angle dispersion at the expense of range?

So do I have two bad radios, or is this a characteristic of superhet receivers, or perhaps are the FRS designed for hyper-sensitivity at the expense of selectivity, for example?

 

[MichaelLAX]

4 hours ago, bd348 said:

So do I have two bad radios, or is this a characteristic of superhet receivers, or perhaps are the FRS designed for hyper-sensitivity at the expense of selectivity, for example?

This phenomena happens at the radio's "fringe" area, where of course everything, line of sight, objects in the way, etc. reduces the radio's range to have "hot spots" and "cold spots."

It is why I added a short coax to my rooftop antenna's coax switch to my analog/DMR RD-5R HT so that I could sit in my "easy chair" and communicate consistently without sudden drop outs as I moved in my chair with the HT's original antenna.

As I recall from my days studying radio theory, the superhet was invented to solve the problem of superregen radio's having poor selectivity; that is, an inability to clearly separate two signal on adjoining frequencies.  I don't seem to recall that it added any increased sensitivity to the radio in and of itself; that is, the ability to receive the same signal at a further distance.

So it just seems that your FRS radios just have a "hotter" front end design in their receivers than your Wouxun, or perhaps better squelch control.

I'll look forward to what the radio super-nerds here have to say about this issue! 

[bd348]

Now to start planning an attic antenna!

[MichaelLAX]

5 hours ago, bd348 said:

Now to start planning an attic antenna!

It really is the best way to enjoy GMRS from your easy chair!

[KAF6045]

I have a similar problem with NOAA Weather broadcasts.

I can stand in my driveway, near the kitchen door, and get perfect reception. Walk 5-8 feet down the driveway -- nothing. Continue walking down the driveway and it will receive well again.

Basically, around my house, I have these 10ft circles of reception, with dead spots between them.

[bd348]

Found a specific place to put a base antenna near a window.  Again, a few inches either way makes all the difference, but at the moment everything is good.  RG-8 for 12 feet, and an 18" thin cable adapter for the handheld.

[bd348]

New issue: Strong signal from a repeater.  Reception audio goes in and out about once per second while signal strength is solid full scale and steady.  Both Wouxun handhelds do this, using basic antenna or 15" whip or 44" base antenna.  The FRS radio audio stays steady.  Overloaded?

[WRVT464]

I noticed the same issue on my new UV9G Pro. However the same issue shows up on my FT60 that's programmed to receive GRMS frequencies. S-meter on the UV9G seems to always indicate a high signal strength no matter what it actually sounds like. Maybe it's a Wouxon characteristic or just a GRMS thing. Hopefully one of the more experienced users can provide some insight.

[Sshannon]

23 hours ago, bd348 said:

New issue: Strong signal from a repeater.  Reception audio goes in and out about once per second while signal strength is solid full scale and steady.  Both Wouxun handhelds do this, using basic antenna or 15" whip or 44" base antenna.  The FRS radio audio stays steady.  Overloaded?

Maybe it’s a problem that affects the more selective receivers. Try it with some other radios. 

[bd348]

The FRS radio is fine.  No loss of audio while at full signal.  And it also receives weaker signals better w/o squelching them, although that may be squelch programming itself.

[Sshannon]

50 minutes ago, bd348 said:

The FRS radio is fine.  No loss of audio while at full signal.  And it also receives weaker signals better w/o squelching them, although that may be squelch programming itself.

I understand that the FRS radio is fine. It almost certainly has a less selective SOC receiver than the superhet KG-S88G, not necessarily less sensitive. Thus it will be less affected by things that can disturb the repeaters transmitted signal. Usually that helps reduce interference from other sources, but it could also cause a poor signal to be rejected, even though you want to hear it.

When I suggested trying other radios I was hoping to detect a pattern of more than a single sample. If other superhet radios do the same thing then you might be able to rule out problems with the Wouxun. 

Are there any wind generators or similar large moving surfaces near you or the repeater? Or the fading in and out maybe caused by multipath propagation. 

[bd348]

I was wondering about wind turbines as well, but this is suburbia, so I doubt it.  And it's two copies of the radio, just different colors.  The mystery continues.

[Sshannon]

4 minutes ago, bd348 said:

I was wondering about wind turbines as well, but this is suburbia, so I doubt it.  And it's two copies of the radio, just different colors.  The mystery continues.

I think it’s still possibly multipath. 

[bd348]

Well I finally got a chance to experiment with the handheld while listening to a long conversation.  The dropping audio problem turned out to be the squelch, and once I turned on the receive DCS for the repeater then the squelch behaved itself and the dropping audio problem went away.  With DCS off the audio was coming and going.  So I suspect a programming or audio circuitry error in the Wouxun KG-S88G, but here is the workaround.