188 Kc

Frank Gentges gentges@itd.nrl.navy.mil
Thu, 18 Mar 1999 03:05:42 +0000 (GMT)

Interesting signal.  I am listening right now to 188.2 and do not hear 
this.  I have heard QYV and several others at this site but I do not hear 
any now.  Your may be hearing a computer as certain loops can give rise 
to a carrier in the LF band when executing a particular loop.  Probably 
in or very near your house.  Less likely is heavy industrial induction 
heating furnace which would probably be local within several miles.

Right at the noise floor my NRD525 processor seems to be generating FSK 
like signals that were driving me crazy until I found they were there 
even without an antenna.  I added an LF preamp and the noise now 
overrides these pesky processor spurious signals.

My listening is primarly trashed with 60Hz spikes from neighbor's SCR 
light dimmers.  It is amazing what I can hear when these spikes are 
gone.  Make sure you cannot hear a bunch of 60Hz related stuff when your 
receiver is in wideband (3kHz or more) and in the AM mode.  That setting 
shows up these spikes.  At narrow bandwidths the spikes are more like 
random noise but still do a lot of damage to your noise floor.  

I have not heard TH from New Jersey for several days but it is a real
consistant weak signal down here and should be copyable there in York.  I
find 500Hz bandwidth to generally let in too much noise to dig for the weak
ones.  I use a 200Hz crystal filter and gain quite a bit in signal detection. 
The 100Hz position on the R-390A also does well with the built-in audio

If you have a 60Hz problem you might also try an LF isolation 
transformer in your antenna line to cut way down the powerline ground 
currents flowing to your antenna.  When you have it right, LF will sound 
about like 80 meters with no 60Hz.  You might find several 60Hz sources 
around your house and just keep watching your S meter as your try 
different fixes.  I have a "torcharre" lamp with a dimmer that must be 
turned of for me to monitor LF no matter what dimmer setting is used.

Enough rambling, hope my comments help you or other tacoistas.

Frank K0BRA

On Wed, 17 Mar 1999, Bob RIESE wrote:

> I have been monitoring 188.2 using Spectrogram looking for QYV a beacon
> from the Pitsburg area. He is at 188.570. As I look on or about this
> frequency I am seeing a strong signal higher at about at 188.8 +-  which
> has a 3 second carrier a 30 second no carrier and then a 30 second
> carrier 3 second no carrier and another 30 second carrier, sounds like
> someone tuning up but appears at random and may appear once or twice an
> hour.,. this is a very loud signal and is audible in the rcv speaker as
> well  perhaps an S 2/3 
> I only monitor in the evening so I notice this then, any Ideas .. anyone
> know of anyone testing ??
> Bob K3DJC York Pa FM19
> ___________________________________________________________________
> You don't need to buy Internet access to use free Internet e-mail.
> Get completely free e-mail from Juno at http://www.juno.com/getjuno.html
> or call Juno at (800) 654-JUNO [654-5866]