WOW, what a difference!

KI6ABZ · #1 (**permalink**) 04-24-2009, 01:24 AM

I was fooling with the Grundig tonight in a last ditch effort to hear anyhing, anything at all.

A little background: I live in a box between 3 mountains. I have high-voltage power lines about 1000' away and a set of "regular" power lines going by about 15' outside my bedroom window - right where my entry point is for my antennas.

So when I plugged in my Grundig, laid out 50' of wire, and got lots of static, I assumed it was the power lines or a noisy transformer. I couldn't quite make out any of the beacons; the strongest was just barely intelligible over the static, and I could only hear VERY close or VERY powerful amateur stations. I picked up a guy in Arizona and Utah, both of whom were running 1000+ watts. Another guy came in very clearly, but as it turns out, he's only 20 or so miles away.

So this afternoon, I thought I'd try one more time... I put the radio in my truck, about 60' away from the power lines, and turned it on. I could get 3 of the time beacons (from Colorado.. I'm in San Diego county) with the built-in antenna!

I went back to my room and started laying out an antenna again... STATIC.

Odd.

I moved the radio about 20' away from its resting place, and the static disappeared. Curious, I went back to my desk and turned off the computer, the UPS, and the power strip... the static went away. I finally narrowed it down to a stupid USB HUB of all things!!

So now I can hear all of the time beacons very clearly. Obviously, 15 and , 20 come in better during the day, but I was VERY impressed with 5000.. it sounds clear as a bell. I started listening on 80 meters and 40 meters... WOW! Were befoer I heard maybe 1 QSO, I'm now hearing 3 or 4 overlapping conversations in one place. I caught a guy in Wyoming talking to an Arizonan, and they were both so clear that they could have been in my back yard. I even caught a very readable call from someone on the East coast, telling a friend he was going to bed.

So I have to confess to being very impressed with the Grundig 750 and with the ability to hear HF signals, even in a bad spot. I was very disappointed with the results I was getting over the last week; I was about to give up on HF, but tonight's experience has been totally different. After hearing several very clear conversations, I am once again determined to get my General (and eventually my Extra) class.

ridgescan · #2 (**permalink**) 04-24-2009, 11:28 AM

Well that's great news man! This is exactly what I experienced when I haphazardly connected my Diamond discone to my R75 one day. I got criticized a lot when I tried to show how it really brings in clean reliable signals-but it still remains a neat discovery here. It sure makes SW monitoring a lot more fulfilling when you achieve clarity! Good for you and that cool rig

I for one look forward to hearing your SW catches!

KI6ABZ · #3 (**permalink**) 04-24-2009, 11:46 AM

As soon as one of my scanners sells, I'm going to get an HF transceiver (there's a used Icom at the local HRO; I'm hoping I don't miss out on it). When I do, I'll post about it here; it'll be interesting to see the difference between a dedicated communications receiver and a broadcast receiver like the Grundig.

ridgescan · #4 (**permalink**) 04-24-2009, 10:32 PM

I frequently visit an HRO here in the area, and the guy who runs it told me that the receiver in the transceiver is a little better. I wound up getting the R75 anyway

and I am very happy with its performance. Yeah it'll be interesting to see what you find.

nickcarr · #5 (**permalink**) 04-25-2009, 05:21 PM

Quote:

Originally Posted by KI6ABZ

As soon as one of my scanners sells, I'm going to get an HF transceiver (there's a used Icom at the local HRO; I'm hoping I don't miss out on it). When I do, I'll post about it here; it'll be interesting to see the difference between a dedicated communications receiver and a broadcast receiver like the Grundig.

It depends on the age of the transceiver. If you're talking about one that was made in the last 5 years, then there's no comparison. Even some older models will outperform most SW portables.

The sensitivity, selectivity and noise reduction features are greatly improved in transceivers of today.

SkipSanders · #6 (**permalink**) 04-26-2009, 12:27 PM

This is one of the reasons to use coax cable to an antenna outside, as far as possible from your computer, which most certainly is a source of HF 'noise'. It creates noise all the way to VHF and beyond, actually.

KI6ABZ · #7 (**permalink**) 04-26-2009, 12:36 PM

Coax does help a little, but the hub made so much noise that it was messing directly with the receiver; even with no antenna, I got a horrible whine.

lanbergld · #8 (**permalink**) 06-30-2009, 02:56 PM

I never have my computer on when monitoring the airwaves. Once its time for my late-evening utility Dxing, the computer goes right off. I even shut off all lights except for one (I need to see to log with my pencil and paper). It doesn't matter what receiver I'm using.

I know that a lot of folks have radios next to the PC, and on top of other running radios etc. but for serious Dxing that just defeats the purpose. Why add interference when you don't have to?

Larry Lanberg

Richmond VA