Weird, no Modulation

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Scipio Kid
Posts: 213
Joined: Monday, 18 July 2016, 7:31 AM
Radio: Cobra 29 LX Tweaked
Antenna: Crummy
Name: Scipio
Location: Out West in Herriman

Weird, no Modulation

Post by Scipio Kid » Wednesday, 19 July 2017, 9:35 AM

Had to run and move a motorhome that hadn't run in 4 years. Got it going and noticed it had an real dirty, little in-dash Midalnd radio. I had to clean it up just to see what the buttons were for. I fired it up and had static, the antenna looked OK and I called for radio check, with no response. Didn't have an SWR meter but it seemed to be working. When I keyed up there was nothing to indicate I was putting out. It had one of those light meters that lit up with Rx but went blank during Tx. I figured it wasn't transmitting.

A friend drove the motorhome, I was in my pickup with a tweaked Cobra 29 Chrome, and the car my friend came in had a little Cobra Ultra II in it. The gal driving the car was from Oregon and really confused about our route so we told her just stay close and stay on the radio (channel 22). I've had the Cobra in the pickup for 5 or 6 weeks and it's been a good one.

As we took off, I said something to the motorhome driver. When he responded I got a good strong signal, but no modulation, just quiet. I knew he was hearing me because I told him to hit the brakes or turn signals and he did. I called for the gal behind me and got no response from her and figured she didn't know how to use the radio. The entire trip, I'd make comments and get back a strong signal but nothing else. I turned the squelch down to see if I could pick up anything but got nothing but silence when they'd transmit. It made sense to me that the Midland was broken. We drove for about an hour and nothing changed. But I was surprised when they told me the car and the motorhome had been talking back and forth the whole trip. They could both hear me but I never heard either of them! It seemed both those little junky radios were working fine and my Cobra was the screwed up one. The weird thing was, I was getting other noise, skip etc. only dead key silence when they transmitted.

I was late for something so didn't pursue it there and took off and was on the freeway within a couple minutes. Thinking maybe a close, strong signal was somehow messing up my Rx, I switched over to channel 19 and hailed the first rig I saw, he was right next to me and came back loud and clear. I talked to 5 or 6 other truckers and all was normal, they all came in strong, loud and clear and said I was doing the same.

So it would seem, my radio was good and the two other radios were broken BUT, somehow worked between themselves with me in between, not hearing either of them. Either that, or somehow, my radio was way off (Rx only) frequency on channel 22 and back on frequency when I switched to 19.

Anyone ever heard of anything like this?

Happy Trails

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