Both me and the wife deeply appreciate the leaving of the light on for us. But please be patient for those replacement batteries! 😀
Looks like some good DX'ing reports going on. I will have to fire up the Motorola and see if the blanket of snow will help pull in some of these stations being heard.
RFB
Tonight just after 11 PM CST I did a scan of the long wave dial, which was set on the default setting of 9kHz, and on 216kHz I detected what sounded like splash-over from the edge of an amplitude modulated signal.
The next slot going up was 225kHz, where a beacon is audible.
Using a trick taught me by a part15.us member, I pushed the tuning control and switched to 1kHz stepping mode.
On a band of seven 1kHz channels I heard a radio station, spread from 217 to 223kHz, with the center of the signal at 220kHz. Right at that time the station identified itself as KMOX, a local 50kW station at 1120kHz AM.
I bet somebody has a low power transmitter and is re-airing their favorite station.
What else could it be?
Yesterday I was on the phone with International Crystal Manufacturing and was all set to order crystals for the LowFER transmitter oscillator schematic by Lyle Kohler, k0lr, as linked here
http://www.nutstreet.net/k0lr/lftx.htm
Trouble is, that link is gone.
The guy at ICM asked "what capacitance?" and looking at my printout pf Lyle's transmitter, there is no mention of the capacitance or any other properties of the crystal, except that it is divide-down by 16, 32, 64 or 128.
ICM told me the crystals in the 4M to 20M range are most economical.
So the LowFER crystals are on hold while I study crystals so as to become conversant with "their capacitance" and how to estimate the need.
By the way, who first submitted that link by Mr. Kohler?
Well if the crystal is running an oscillator within the divider chip or another IC, look up that chip's spec sheet and get the data from there, or simply give ICM the chip number and they can determine what capacitance the crystal needs to be.
RFB
actually KMOX on 220 would just be an image of some kind.
I get the same thing with 1080 on 180.
Let's talk about the "image" phenomenon, which has been mentioned frequently in the threads.
Is there a single explanation for these images?
Or are there different situations that can generate images.
Here's an example of an image that I call a phantom, it is a strong audio signal from 850kHz AM being projected at 800kHz. My theory for this particular situation is "front-end overload" of the receiver, because this 5kW station is very nearby.
Another circumstance that I've mentioned is hearing a station from 1430kHz way down on 530kHz, which seemed to be gone during a period when an Illionois traffic TIS station was on 530.
Image signals are usually caused by intermod of the IF frequency, which is either 450 or 455 Khz for in-band image reception.
For the out of band image reception, it's usually just a harmonic your picking up off the high powered signal.
I pick up KTWO AM 1030's signal at 1230 and 630 during the day when they run the omni pattern. At night when they switch to the clover leaf type patter, both image signals disappear.
KTWO AM 1030 is a clear channel 50Kw station, both day and night. At night they just change the pattern. Two towers located south of the city.
RFB
When I was growing up, we (my family and I) had a local
station right in town on 1550 kHz AM. And of course, when
the radio was tuned to 640 AM, we would also get the
1550 signal there. Later on, the transmitter was
moved farther away, and that problem didn't
exist anymore.
i just tried to write a huge explanation of how
superhet radios work, and why that sort of thing happens.
I was very proud of myself. But then, after writing for a long time,
I started changing words and sentences. Then I
started getting confused. So I scrapped the whole
thing. (I tend to be pretty wordy, anyway.)
When it comes right down to it, though, most radios
are not perfect. Zillions of radios have had the same
basic circuit design for decades and decades. And they
will tend to pick up the desired signal really well. Then,
if things work out "right," they will tend to get another
frequency, too. With the same dial setting - which is the
image signal.
But hopefully, only if that image signal is very strong. There is
an electronic explanation for this. And for zillions of radios -
the mathematical relationship between the desired signal
and the image is pretty much the same.
Of course, radios with improved (and more complicated)
circuitry do not have THIS kind of image trouble.
But they have other problems.
There is a problem with some of my Long Wave radios.
I have quite a few radios that tune the Long Wave range.
Some of the low end models tend to hear my local
50,000 watt flamethrower "down in the LW basement." The big
local flamethrower is WTIC AM 1080. And it is only 3 miles away.
For some reason, the low end LW radios get WTIC on 180 kHz.
And I do not know why this is.
Best Wishes,
Bruce, DOGRADIO STUDIO 2
P.S. I just looked back up at some of the comments.
i saw that Mr. Crow also has a local AM 1080. And
he also gets that station on 180. Interesting coincidence.
In addition Bruce,
WTIC (your 1080) and KRLD(my 1080)
are owned by the Same Company (CBS Radio)
They also have similar formats
(WTIC - News/Talk)(KRLD - NewsRadio)
They also have the same directional pattern.
KRLD Aims away from WTIC, and WTIC aims away from KRLD.
They also signed on within a year of Eachother.
WTIC 1925 KRLD 1926
I have heard KRLD here in Connecticut when
WTIC has been off. I think that's really neat.
I understand that the chief engineer of KRLD
and the chief engineer of WTIC are good friends!
At least that went by on the local broadcast rumor
mill a while back.
I heard a DX test years ago, where WTIC shut down
so DXers here could hear KRLD. Then after that
KRLD shut down so folks out your way could log WTIC.
You have to love that radio stuff.
Best Wishes,
Bruce, DOGRADIO STUDIO 2
I have been reading your post. I have a sageon ATS803A Receiver.
It is dual conversion and has AM ,CW,LS ,USb
Anyways radio really works well on the 160-190Khz range. You can even put
a external antenna on it if you really want a big antenna out side.
i have been making these transmitters since I was 9 years old,but really
could never find anyone interested in this band till now.
I use to broadcast music over this band and when I was about 15 years of
age I actually picked up someone broadcasting weather reports.
I still love this band. I heard someone mention the capacitance on the
crystals. That does not really matter on the type of transmitter you are
talking about. I use to due that with my transmitters. They use a divider
circuit..I use to use one that divided by 10.
So a 1600Khz or 1.6 mhz crystal put you right at 160 Khz.
Alot of ham that work the 160 meter band had crystal the work in the 1.8Mhz
band and if you divided them down they would end up around 180Khz to 190Khz.
Right in the band we want.
Anyways I would need to look at what chip divide by 10, but I think it
was a TTL chip called the 7490 chip if I am wrong please clorrect me.
Here a site that explains how that chip works. Anyways you can use Crystals
just about the Broadcast band to get down to the LF band by just using
a divide circuit.
Check out this link
http://electronics.howstuffworks.com/gadgets/clocks-watches/digital-clock5.htm
Anyways Since the LF band is so low in frequency I was able to make stable
oscilator Circuits with just a Coil and capacitor...I sheilded them
well and they stood right on frquency with no drift. You would be how suprise
how well transmitters stay on frequency when it is very low.
Also try the Cmos 555 chip it is good to 2 mhz in frequency. You can set up an
RC circuit for a 162Khz. Now you will have to shape it with a PI circuit
since it is a Square wave out put.
The other Chip the make a great sine wave is the LM741 op amp chip. this
can work up to 1 Mhz. I made great LC oscilators with this chip only using
RC circuits,but a Crystal can be hooked on to that chip for a great output.
Anyways I have been playing with this band for years and have came up with
really good designs for transmitters and receivers. Even Morse code receivers.
By the way I have design transmitters down in the 8 to 15 khz range which there
is no FCC rules about since it is all experimental down in those frequencies.
Yes RF work in those ranges read about it.
Thanks
Sean
I posted a mesage but it under reveiw..
anyways I tried to cover this band also.
It a very experimental band,and you may be interested in it.
VLF Amateur Band Reception (8.7-9.1kHz)
Anyways there is no limit on your transmitt power.
Receivers are easy to build and transmitter are also.
Have fun
Sean
Just so you will know, this site has an automated "spam catcher" which triggers on certain key words or phrases. I don't know what these are but when it happens the post is entered as "Unpublished" which makes it available to the poster and the moderators. Sometimes it takes a while for a moderator to check it and publish it so be patient if this happens. Don't take offense, though it can be annoying it does help protect the site from trash.
Neil
I used to play with VLF stuff years ago. Was interesting to listen to subs and natural EM phenomena. These days there are lots of natural EM stuff to tune into with all the CME activity going on.
But after a couple of years making my ears ring from static and noise, same with DX'ing, got tired of it and started listening to bands with something other than clicks and pops and buzz saw buzzing.
Currently my LW TX uses a Datakit PLL working an LC oscillator and covers 120Khz out to 300Khz no sweat. A3E, CW and FM by the push of a button. 99 percent of the time it's operating in A3E mode on 162Khz @ about 900mW PEP into a 50 foot slopped long wire above a ground system, angled facing towards the city with a river and mountain behind it. Works great!
RFB
HI So
What are you transmitting on it?
Sean