funny issue

Status
Not open for further replies.

k1agh

Member
Joined
May 8, 2012
Messages
413
Location
Maine
On my Radio Shack® Synthesized World Receiver why do I get a whistling sound on the shortwave frequencies? Its loud and annoying and I can't figure out how to get it to go away. No outside antenna hooked up and nothing has changed.
 
S

screamin72

Guest
If you still have your receipt and still under warranty please get yourself a refund or echange.
 

Boombox

Member
Joined
Sep 2, 2012
Messages
884
You're sure you don't have the BFO switched on by accident? I once had my radio switched to 'Local' by accident and wondered why the radio wasn't picking up much, until I checked all the buttons. It's easy to do, leave a button switched on or off......

Is the whistling on all frequencies? Does it vary in tone? Have you taken the radio outside your house to see if it gets louder or weaker? Before taking the radio back I'd try moving the radio around from room to room or outside the house, and see if there's a difference.

It is possible it's not the radio, but it could be RFI.

My computer puts out whistles in various parts of the SW spectrum. My printer will cover the 20 meter ham band with racket now and then if I haven't unplugged it. I have an older DVD player that put whistles and other noises in various places of the SW spectrum, even when turned off.
 

majoco

Member
Joined
Dec 25, 2008
Messages
3,574
Location
New Zealand
BFO needs a signal to beat with and the OP said
No outside antenna hooked up and nothing has changed.
so I don't think it's that. Just check that there is no other antenna connected, a whip perhaps even if it is pushed down. SW only is a clue - does it do it on the BC band?

Refund or replace please.....
 

Boombox

Member
Joined
Sep 2, 2012
Messages
884
Depending on where he is -- I think he's on the East Coast of the US, where SW signal strengths are strong -- it could still be receiving SW on the whip, and he may have forgot to switch the BFO.

I just threw that suggestion out just in case, because I had a similar thing happen to me where I thought it was the radio and it wasn't.

Without an external antenna hooked up I'd check for RFI before returning the radio.

I think Tominbelfast has another SW radio -- if the same noise is on the other radio, it would probably be RFI.

If it isn't, you're correct, it may be something wrong with the World Receiver.

Either pull the batteries out and wait 15 minutes and let the microprocessor reset, and see if that changes it, or just take it to Radio Shack and replace it, they still carry the radios.
 

wa1nic

Member
Premium Subscriber
Joined
May 28, 2012
Messages
263
Location
Westfield, Ma
All frequencies, or only a few discrete frequencies?

If it is all frequencies then there is possibly some sort of internal oscillation that isn't supposed to be there.

A loose internal connection (to a shield for instance) could cause that. An improper alignment could cause that. A still active warantee would be the best fix for it.

If it is only on a few discrete frequencies, well. in an "all band" receiver that is going to happen now and then. All the internal oscillators and also mixed products of said oscillators radiate far enough that the receiver can pick up it's own internal stuff. A good radio design tries to minimize them, but there still may be a few left.

Rick
 

ridgescan

Member
Joined
Apr 1, 2008
Messages
4,674
Location
San Francisco, Ca.
I get a "heterodyne" high pitch whistle on certain AM broadcasts in the shortwave bands, which are due to close-by frequency stations' signals bleeding into my desired one's carrier. For example, BBC out of Singapore here on 9740kHz in the morning (7am PST) has a killer het whistle that I can't even begin to eliminate with my higher end Icom r71a's PBT or narrow filters. However, my r75's ANF kills it. If you get this on ALL the stations you tune, it likely could be a fault in the RF stage of your radio.
 

k1agh

Member
Joined
May 8, 2012
Messages
413
Location
Maine
I changed the batteries and it worked. The low battery indicator wasn't on so I didn't think to check those. I guess I need to find a power adaptor for it.
 

Boombox

Member
Joined
Sep 2, 2012
Messages
884
I changed the batteries and it worked. The low battery indicator wasn't on so I didn't think to check those. I guess I need to find a power adaptor for it.
Tom, my RS World Receiver is also a battery hog. Definitely not as bad as my DX-398, but the World Receiver uses batteries more than my other 4 x AA, 6 volt digital radios.

I think the battery meter may be accurate, but when the battery meter shows 2 or three numbers, usually that means its time to keep some extra AA's handy.

I use a 4 x D Cell battery pack with mine, which I made using 4 x D Cell battery holder, a bit of speaker cable, and an adapter plug from Radio Shack (making sure I got the polarity right).

Using 4 D Cells that way you can avoid any RFI issues from an AC Adapter, and still have some measure of portability. Or just keep it around as a quick backup. Because I have several 6 volt radios with the same adapter jack (and same polarity, center negative), the battery pack comes in handy for me.
 
Status
Not open for further replies.
Top