Messages

1

Longwave Loggings / Re: 180 KHz Unknown digital

« on: August 24, 2024, 1536 UTC »

Maybe a day late and a dollar short, But 180 is kind of a watering hole for the LOWFER band (160 to 190 kHz) used for unlicenced legal transmission. Theres a good chance you are hearing WSPR or WSJT modes and if they are loud, you are probably not far from the TX. 

Theres also a section of this message board for LOWFER, MEDFER, and HIFER beacons.  These are all extremely restricted in size and power (to be legal) but LOWFER is the most popular. 

2

Equipment / Re: Please recommend some good MW and LW DX radios

« on: July 06, 2020, 1654 UTC »

I have a tecsun pl-880, and as far as portables go, it is pretty good, but nothing in a similar price range seems to compare to selective voltmeters/selective level meters.
I have a rycom3121a that i got for less money than my tecsun which has a tuning range of 10 to 1600 KHz and a 100 Hz cw filter.  there are several companies that make (or used to make) these. Rycom is probably the easiest to find, but Wandel and Goltermann, HP, Rohde&Schwarz, and a few others also made them.  Price range is anywhere from 100 USD to thousands, depending on what you are looking for.  Even the cheap ones will almost always outperform any common radio receiver below 500 KHz though.
Best of Luck -TeC

3

Equipment / Re: What are you using for SWLing?

« on: July 06, 2020, 1647 UTC »

For what its worth, keep in mind that there are a lot of "moving parts" to shortwave DX'ng, i.e. weather, time of day, solar activity, seasonal fluctuations, etc etc so don't get discouraged if you don't get "all the hits all the time".   Enjoy the hunt - its all part of the fun.

This is certainly true. I used to live in a low noise area with a good antenna, now I live in an apartment near the city. I heard things there with cheap receivers that I cannot hear here with world class communications receivers. a good receiver is a great help, but so is a good antenna, location, etc.

4

Equipment / Re: Grounding A Radio

« on: May 21, 2020, 0102 UTC »

the only ground I have is the one on the third prong of the plug. at least for the radios. The antennas are coupled to the radio via an isolation transformer. the antenna ground for the vertical is a water pipe.  This avoids any ground loops. I don't have any other grounds aside from that.

5

Equipment / Re: L band antennas

« on: April 11, 2020, 0408 UTC »

Sorry guys, I didn't get that message originally, but if I use chrome it shows up.
I have been looking at this guys website for years, and I doubt that the posting is legitamate, but its probably best to play it safe.
https://imgur.com/EtzwGm5
Here's the drawing of the antenna, The designer (and owner of the problematic website) is Matjaz Vidmar, S53MV. credit for the drawing goes to him, not me.

6

Longwave Loggings / MOG is back!

« on: April 09, 2020, 0432 UTC »

heard MOG 404 Khz Montague CA for the first time in the better part of a year. seems like the signal is stronger than before. And I thought it was gone forever

7

Equipment / Re: L band antennas

« on: April 09, 2020, 0405 UTC »

If you are feeling ambitious
http://lea.hamradio.si/~s53mv/wumca/cavity.html
these are some nicely built antennas

8

Equipment / Re: Loop or Longwire?

« on: April 03, 2020, 0236 UTC »

Are you specifically interested in low frequency? high frequency? or just general coverage?
I rarely venture above 10 MHz and spend most of my time below 5, and I prefer the wire any day, but I used to use a loop for HF ham radio a lot, and they're pretty nice.

9

Longwave Loggings / Re: New to longwave

« on: February 23, 2020, 0817 UTC »

It looks like the same thing with a lower stopband attenuation. it probably will work just as well as long as your receiver has a reasonably robust front end. I don't even have a filter on mine, I just rely on the fact that my antenna matching transformer works poorly above 1 mhz. My receiver is actually a demodulator, and can handle a pretty strong input.

another trick that works really well if the strong local interference is on a single frequency is to shunt that one signal to ground with a series resonant circuit, this is effectively a notch filter and will provide vary good rejection on a single frequency.
 
Long story short, any filter is better than none, and you don't need a filter with super high stopband attenuation to get decent results. 

10

Longwave Loggings / Re: New to longwave

« on: February 22, 2020, 1939 UTC »

If you have about 100 bucks, and dont feel like building a filter, I have heard good things about these filters from Kiwa Electronics
https://kiwa-electronics.com/500-khz-low-pass-filter-3.html
To clarify, I don't work for this guy, nor do i have one, just passing along stuff I heard about.
 Best of luck in radios' basement     -EC
edit-(whoops, looks like its about 140 bucks)

11

Equipment / Re: Test Equipment purchase

« on: February 09, 2020, 0638 UTC »

Good frequency counters sometimes have a mode with 2 inputs where one input is counted and the count is gated by the other. This allows you to compare two signals regardless of the internal clock (or use a better oscillator, gpsdo, etc. on the second input. ) I use this feature a lot for comparing low frequency signals.

12

Longwave Loggings / Re: unid 305

« on: December 15, 2019, 1950 UTC »

I feel like I logged LT once when I lived In Shasta Lake CA, I wont say that officially though unless I can find it in my logs, seems like something I would have posted.
If I did, it certainly wasn't a strong signal

13

Longwave Loggings / Winter 2019 NDBs, Portland Oregon

« on: December 15, 2019, 1833 UTC »

NDB logs for 12/14 19 between 0500z and 0700z


200 UAB Anahim lake BC CAN
214 LU   Abbotsford BC CAN
221 QU  Grande Prarie AB CAN
223 YKA Kamloops BC CAN
236 YZA Ashcroft BC CAN
239 OJ   High Level AB CAN
242 ZT  Port Hardy BC CAN
251 YCD Nanaimo BC CAN
328 5J   Coronation AB CAN
332 VT  Buffalo Narrows SK CAN
338 ZU  Whitecourt AB CAN
341 DB  Burwash YT CAN
343 YZH Slave Lake AB CAN
344 XX  Abbotsford BC CAN
346 YXL Sioux Lookout AB CAN
350 NY  Enderby BC CAN
356 PND Portland OR USA
359 YAZ Tofino BC CAN
359 YQZ Quesnel BC CAN (this one usually beats with YAZ to the extent that they are both difficult to hear properly)
362 RPX Roundup MT USA
368 SX  Cranbrook BC CAN
368 ZP  Sandspit BC CAN (this one usually beats with SX to the extent that they are both difficult to hear properly)
374 EX Kelowna BC CAN
382 YE Fort Nelson BC CAN
395 YL Lynn Lake MB CAN
400 QQ Comox BC CAN


Received using a T antenna (in the attic of my apartment) and a WJ 8718. The antenna is matched with a 100 to 5 turn isolation transformer (100 on the antenna side)

14

Equipment / Re: 9:1 or 49:1 unun for end-fed long/random wire?

« on: October 19, 2019, 0624 UTC »

This may not be relevant to HF stuff, but the antenna I use for NDB reception has a 400:1 transformer (20:1) turns ratio. I have never tried to transmit through it, but it proved the optimal ratio for receiving with my setup.

15

Equipment / Re: Test Equipment for First Time Build

« on: September 25, 2019, 0406 UTC »

In the beginning, I wouldn't bother with a spectrum analyzer. 
+-RH

I, begrudgingly, Agree
I lusted after one of those for a long time, I finally got one (an HP8594E) aaand...
I don't really use it anywhere below a few hundred MHz. I use my scope and frequency counter every day.

my recommended top three (after the usual electrinic stuff such as a multimeter, power supply etc) are;
1. oscilloscope (my preference is analog, but any good scope is good and some digital features are really nice)
2. frequency counter (a cheapie is probably sufficient)
3. signal source. (slightly less important for building transmitters, but good luck building or even fixing a receiver without one. of course a cheap analog one is fine if used with the frequency counter. )

hope this helps _