70 Ft Long Wire

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prcguy

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Now that the main problem is behind you I would like to bring up something that was mentioned earlier in the thread. Connecting your long wire directly to the center conductor of coax is not the best way to do things. Using a 9:1 balun between the coax and wire is proven to smooth out reception across a wide frequency range and it will also slightly isolate the coax and any noise on its shield from the antenna.

Adding a 1:1 choke balun in the coax before it enters the house can also reduce interference from noise picked up on the shield of the coax, which can travel to the antenna feedpoint and get picked up by your receiver. You can make a 9:1 balun for a few $ and for about $7 you can make a good 1:1 choke balun.
 

a29zuk

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Now that the main problem is behind you I would like to bring up something that was mentioned earlier in the thread. Connecting your long wire directly to the center conductor of coax is not the best way to do things. Using a 9:1 balun between the coax and wire is proven to smooth out reception across a wide frequency range and it will also slightly isolate the coax and any noise on its shield from the antenna.

Adding a 1:1 choke balun in the coax before it enters the house can also reduce interference from noise picked up on the shield of the coax, which can travel to the antenna feedpoint and get picked up by your receiver. You can make a 9:1 balun for a few $ and for about $7 you can make a good 1:1 choke balun.

He already has a balun as stated in post 20. He can reinstall it now that he has learned how to tune his receiver.

Jim
 

a29zuk

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Jim, Thanks.. I tuned into 830 which is out of Minneapolis St Paul. I began to work the switched and tuner(s). Whalla ... I figured it out.. It was operator error all along. Thanks for the help. Greg

I'm glad you have a working receiver. Now you can share your station logs with the rest of us in the "Shortwave Broadcast" and "Utilities Listening" forums.

You gotta watch out for that Ridgescan guy, though....he pulls in a lot of good ones!

Jim
 

ridgescan

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Thanks Jim-if that's true it's only cause I'm probably the only one who goes digging in the BC bands for propagation checks most every night.
For bumper41-just a few frequencies for you to whet your shortwave VFO; try these starting about 8pm your time (CST)
5085kHz WTWW Lebanon, Tn.
9395kHx WRMI Florida
4840kHz WWCR Nashville, Tn.
and a couple overseas;
9420kHz Voice of Greece (Helliniki Radiophonia) Avlis
5925kHz Voice of America Selebi-Phikwe (but this one comes on 0400UTC which isn't 'till 11pm your time) so ya gotta stay up late for that one:) it transmits from Botswana baby!!

Otherwise, just spin the dial in these following broadcast bands in your eveningtime (starting at about 7pm CST)
4600-5100kHz
5800-6200kHz
7300-7850kHz
9200-10000kHz

And don't forget Radio New Zealand in the upper band. See if you can catch 'em on 13840kHz.
 

GB46

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Hi, The crazy thing is this radio was purchased by the original owner back in the 80's and was never used. Actuially when I bought it, the box was still sealed and the radio was packaged in its styrofoam. Absolutely mint. I probably just don'y know how to tune it yet. Thanks Greg
I don't mean to be a spoil sport, but I bought a DX-300 back in the 80s brand new, and had lots of trouble with it. Yes, I knew how to use the preselector, etc., but the main problem was stability -- the receiver would drift off frequency, then correct itself, then drift again; it was like an endless loop. This wasn't too bad in AM mode, but it was pretty hard to monitor sideband stations with the voice pitch varying up and down. Of course, that receiver did get me lots of DX with a minimal indoor antenna -- the Voice of Greece and Radio RSA in South Africa from inside a Vancouver apartment is nothing to sneeze at -- but eventually some of the segments of the LED display started flickering, then went out permanently. I hope you have better luck with your DX-300. Maybe I had purchased a lemon from a bad day on the production line. :)
 

Boombox

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Try a shorter piece of wire, to ensure the problem is not the radio. If the problem is not the radio, propagation has been horrible the past several years. Some nights SW is decent, others it's static, and I haven't experienced a truly good shortwave night or morning personally since about 2015 or so.

PS -- if the DX-300 has a preselector (which I think it does), that could be the issue. SW radios with preselectors need the preselector tuned to hear anything.
 

majoco

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If the DX-300 is like the FRG-7, then I found that if you set the MHz select and kHz select to the approximate frequency, then tweak the preselector for max noise, then go back to the MHz and kHz selectors and do it all over again! Try it on a good signal, say Greece on 9420kHz, then you can go hunting either side, constantly tweaking for maximum signal.
 

Boombox

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^^^^^ Also, if it's like the FRG-7, if you have the MHZ dial off a tiny bit, it can reduce reception.

With my FRG-7, dust needs to be blown from the tuner caps periodically. Being that the OP's radio was in a sealed box, it probably has few, if any issues electronically. Just tricky to tune. I know the FRG-7 was until I got the hang of it. I still use mine on MW when I have decent antenna for it.
 

a29zuk

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Yes, it is like the FRG-7. I remember having to tweak the Mhz dial just right to get maximum signal.

Jim
 

majoco

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Does the DX-300 have a "Lock" indication set by the MHz selector? The FRG-7 should be called the "Unlock" light - it's red and goes out when the MHz tuning is 'Locked" - there is a mod to make it go from red to green with a bi-coloured LED but it's something you get used to.
 

a29zuk

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Does the DX-300 have a "Lock" indication set by the MHz selector? The FRG-7 should be called the "Unlock" light - it's red and goes out when the MHz tuning is 'Locked" - there is a mod to make it go from red to green with a bi-coloured LED but it's something you get used to.

I don't remember a light, I think you just had to use your ears.

Jim
 

pjxii

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Hi, good news and thanks to all for your feedback. As it turns out Once I worked the Pre select, Tuner and fine tune. I was able to finally start to pull in stations. I also did not have the atten set to 0 which really opened up everything. I am on my way now. Thanks again.

Good to hear you got the radio's tuning system figured out!

As has been stated by others, shortwave reception has generally been very poor for a while, and will continue to be poor for a while longer due to the sunspot cycle being low now.

A brand new DX-300, wow that's a nice find!

If you can figure out a proper antenna (think ferrite loopstick) you can tune the VLF signals meant for submarine communications all the way down to 15 kHz.
 

bumper41

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So now that I have had some time to test and experiment, I am wondering if I still might have an antennae issue. Here’s my question..... I tuned to a local AM station for testing purposes. On a normal AM/FM radio the signal is loud and clear. On my shortwave receiver, I can hear it on some nights and rarely at all on days. Does that seem logical ??
 

a29zuk

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Have you tried tweaking the Mhz control? Besides the pre selector this needs to fine tuned for a maximum signal. AM(BCB) signals do travel much farther during the nighttime.


Jim
 
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bumper41

The Spark: Heath Kit Crystal Radio 1964
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Have you tried tweaking the Mhz control? Besides the pre selector this needs to fine tuned for a maximum signal. AM(BCB) signals do travel much farther during the nighttime.


Jim
Hi Jim, Yup. Got that fine tune process covered. But shouldn’t an am commercial broadcast station 50 miles away absolutely peak the needle ?
 

ka3jjz

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Many radios have lowered sensitivity on the MW band to reduce the possibility of overloading. I don't know if that radio does, but if so, even with the inboard preselector tuned properly, that could be one explanation. Mike
 

majoco

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On the DX-300 the attenuator switch should be set to the middle position.
 

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