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Topics - Josh

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Artemis is an open source Windows/Linux/MacOS compatible application initially programmed by Marco Dalla Tiezza. It brings the sigidwiki website into an offline searchable database with an easy to use UI. Today version 3.0 was released to the public. The new version has been completely rewritten from scratch in Python, as the previous versions were written in BASIC (a now abandoned programming language). The new version has an improved UI, and paves the path for future improvements.

Spy Numbers / Numbers stations
« on: July 16, 2019, 0313 UTC »
If you wondered just how these numbers sent over the air were decoded and used by their intended recipients, you're going to love this pdf;

For the adhd among us, just scroll down to the section headed "radio grams", otherwise this entire pdf is very enlightening on the ways and means of modern day spies.

Also, spies like us is a great movie, possibly a documentary of some of the greatest successes of the cia.

Software / SDR Console release
« on: July 09, 2019, 2004 UTC »
3.0.10 Release
June 20th, 2019, This is a full release kit. It is a signed kit .


Sdr console is my goto sdr app, features vrx as well as low cpu usage and mem footprint.

Software / SDRuno V1.32 Release
« on: July 09, 2019, 2001 UTC »
SDRuno V1.32 Release

We are pleased to announce the release of v1.32 of SDRuno. The purpose of this release is primarily to add MRC Diversity functionality for the RSPduo, but it also contains other fixes and additions based on customer feedback. Diversity functionality is described on P.78 of the SDRuno User Manual.


Propagation / Attention Propagation Nerds
« on: July 06, 2019, 2212 UTC »
Oscillations of the baseline of solar magnetic field and solar irradiance on a millennial timescale


Recently discovered long-term oscillations of the solar background magnetic field associated with double dynamo waves generated in inner and outer layers of the Sun indicate that the solar activity is heading in the next three decades (20192055) to a Modern grand minimum similar to Maunder one. On the other hand, a reconstruction of solar total irradiance suggests that since the Maunder minimum there is an increase in the cycle-averaged total solar irradiance (TSI) by a value of about 11.5 Wm−2 closely correlated with an increase of the baseline (average) terrestrial temperature. In order to understand these two opposite trends, we calculated the double dynamo summary curve of magnetic field variations backward one hundred thousand years allowing us to confirm strong oscillations of solar activity in regular (11 year) and recently reported grand (350400 year) solar cycles caused by actions of the double solar dynamo.


Thanks to the on-board GNSS receiver integrated in the KiwiSDR, precise time stamps are attached streams of I/Q samples provided by the KiwiSDR, and the use of these time stamps for Time Difference of Arrival (TDoA) geolocation is discussed.

Lightsail-2 is a solar sail experiment which successfully launched on a Space-X Falcon Heavy on 25 June, and was released into orbit on July 2nd. A solar sail is a type of spacecraft that uses a large metallic foil to create propulsion via photons from the sun hitting it. Lightsail-2 is still undergoing testing, so it has not yet deployed it's solar sail, but recent updates indicate that it is healthy.

Hanza, Okinawa - May 2007
Demolition of Hanza CDAA March 13 - June 30, 2007

Shortwave Broadcast / 11150 Voice Of Hope 22JUN19
« on: June 22, 2019, 1804 UTC »
11150 Voice Of Hope 1345Z 22JUN19
Clean sig, S2/5, adults and children in Asian lang.

FM DX Loggings / 97X Owensboro's Best Rock
« on: June 22, 2019, 0515 UTC »
Hadn't really checked rx performance on the R7000 just gotten (see Project 7000 thread for details) so applied ac line and a piece of wire a few feet long into the center contact of the N connector since running out of freaking N adapters for any decent v/uhf antenna. Anyway after becoming fearful that the rig actually might be deaf as the seller embellished, wriggling the wire suddenly brought in the fmbc band! Wire barely had any exposed metal, so its position was critical. I had pretuned fmbc knowing several strong stations were in rx range of even insensitive fm radios.

I tuned around the band and there's stations on every channel, more than one in most cases. Landing on a rock track (Linkin Park - Numb 12:50 local time) I stayed long enough to catch an id, 97X (97.1) out of the Evansville area, 58 miles away by air. Not too shabby for a R7000 with few feet of wire laying horizontally inside a place with aluminum siding.


Equipment / V/UHF antennas other than Disconeys
« on: June 21, 2019, 1802 UTC »
Are there other passive broadband V/UHF antennas than the lowly Discone? I've often used HAM multiband vertical antennas such as those made by Comet, Diamond, and so on for scanning, but they show pronounced peaks only at the HAM bands and only by coincidence is there low swr elsewhere in the spectrum. Staying away from active antennae for now.

Any input appreciated.

Equipment / Project 7000
« on: June 20, 2019, 2332 UTC »

I've been wanting one of these bad boys for ages.
 25 to 2000mHz in all modes, decent scanning, was a workhorse for int agencies and military all over the world for some time, nothing did what this thing could for the dollar when it was in production. Some still consider it better than a lot of the current stand alone v/uhf rx available today. The NSA bought these and its brother the R71 by the pallet, as did a lot of the rest of the three letter gangs. If you have each of these, you have NSA twins. One of the east coast radio vendors who sold those same pallets of R71/R7000 to our fed overlords even offered a upconverter mod option to enable the R7000 to cover vlf to 2GHz. I read somewhere the dynamic range wasn't very good on hf with these mods.


I've been keeping an eye on one a friend has had for decades, and after decades of use it has the dread iCom display failure as noted by so many R71 owners where the bypass caps in the display circuit dry out and the display goes along with it. This is a non trivial repair so I wasn't looking forward to doing it on my friends rig after purchase. He wants a bit more for it than I want to spend right now but I'm certain I'll end up with it eventually as it's still a good deal.

So the other day I saw an ad at qth for an Icom IC-R7000. It showed illuminated display such as vfo and mode in the included pic, but no rx was listed as the issue. It looked like new in the pic. Seller wanted $75 for it, shipping to be discussed.

I don't really have the money to spare, and considering how long I've been eyeing my friends R7000 that I know for certain works but needs display caps replaced this was a risky deal in numerous ways compared to my friends, but I emailed him to ask what the symptoms were and for shipping to my locale.

He replied that he had checked the internal battery and it was good, and that "it worked a week or two ago and now no rx". He had spent something around $32 to ship a similar item close to me recently and he offered it to me for $100 shipped to my door.

Impulse took over and I sent the money. He also said I was 1st of 3 HAMs who were on the waiting list if a deal failed. I figure looking as good as it did, I might be able to flip it for a tidy sum if repair was out of my league and/or pocketbook.

So some days go by and he informs me he sent it double boxed via USPS, who said it'd be here this Friday, it was here by 0857 local time this am (Thurs) as he paid for 3 day delivery.

Had some car repair work to distract me from the all important radio unboxing/postmortem and finally got around to opening the boxes.

Indeed it looks like new, no cig or smoke smell, all controls operated smoothly, no dings or scratches. Got an ac cord, plugged the ac cord into the wall and into the radio and held my breath as I pressed the power switch.

Everything lighted up as expected, modes changed, could hear the mixer relay switch for 1gHz operation, vfo worked fine, and noted the smeter level changed slightly as I went from mode to mode. Display is bright like when an iCom has good display caps, and dimmer switch works. Squelch worked too per rx signal indicator light.

I don't recall if the remote control internal option is required for that indicator to light, but it does when the remote switch is pressed. Turned squelch full counterclockwise and audio full clockwise, not a peep from the internal speaker. Then I turned the audio way down for the next test as everything so far indicated control panel if not rf life of at least a minimal sort.

Plugged in a set of phones fully preparing myself for there to be nothing, turned up the volume, and the glorious rush of an audio amp ensued! Elation and despair as I got a very nice R7000 by way of theft as it were; for whatever reason, the internal speaker isn't functioning at all and that seems to be its only malfunction noted so far.

So, have to open the case and see why the internal speaker isn't firing, I never use internal speakers save for testing but they're very important as that piece of test gear.

Anyway, Project 7000 entails a cheap RTL sdr to do the panadaptor display when desired, and the R7000 to fulfill spectrum surveillance duties, especially of the mil air variety.

There are a number of worthy mods to do to a R7000, some of them from the SETI guys and others who use these things as radio telescopes. Wonder if it will hear the hydrogen line on a discone.


Also, anything this old will need a full alignment to come close to or exceed the rx specs as stated in the manual so there's that to do also.

I know this thing's an antique and sdr rigs are so much more capable. I have a RSP2 that covers more spectrum than the R7000 does and offers wider spectrum display than that capable of an R7000 IF output, but that sdr mandates the use of a pc, and there's no gratifying tuning knob.

Knobs are nice to have.

more later

Utility / WWV 10, 15, 20, 25mHz
« on: June 20, 2019, 2024 UTC »
WWV 10, 15, 20, 25mHz were all copied @ 1808Z 20JUN19
10 and 15 were strongest, with 20 a close second and 25 in and out of noise level but good enough to set the reference oscillator when they were sending the 500/600Hz tones.

Hi guys, I just wrote custom ExtIO driver for RTLSDR dongle, may be it will be interested for someone.
It has integrated DC remove filter and allows to setup any possible sample rate.
This ExtIO works through librtlsdr.dll from OSMOCOM (librtlsdr.dll should be renamed to rtlsdr.dll).

I wrote it because existing ExtIO_RTLSDR for some reason doesn't works in Direct Sampling mode with SDRUno. So, there is no way to receive MF and HF stations (0-14 MHz) with SDRUno and RTLSDR. This ExtIO works ok in such mode. Also I added DC remove filter, because it is missing from SDRUno.ExtIO, you can enable/disable it from ExtIO settings window.

Equipment / Gear prices
« on: June 14, 2019, 2122 UTC »
Lately I've seen a lot of HAM rigs come waaaaaay down in price, mostly after the release of the IC7300. Icom priced the 7300 so low it wiped out the used market, often a used 7300 goes for less than $900, very tempting. So with the used market going flat I come across this;
W314 Icom IC-756Pro   $439.95
HF/VHF Amateur Transceiver
The display is dim but there's a led replacement for the cfl that's fairly cheap and not too absurd to install. I've seen Pro original models with good displays going for $550 on qth.

The same dsp chips in the JRC NRD545 are inside the Icom 756Pro series so performance will be very similar in a lot of ways, and as a plus the Pros transmit 100w hf thru 6m, yet the NRD545 still commands a fairly high price, does not offer the fantastic fish finder every pro features, and is rx only.
That being said, they're my fav JRC and I've spent time with all of them from the 505 to the 545.

I note the Drake R8A/B also seems to be holding up in perceived value.

Don't even mention the likes of the RX340 or similar gov/commercial offerings, they still command several thousand dollars in the used market yet don't have a fish finder. A lowly $25 RTL V3 has more raw capability, only lacking in dynamic range, that the WJ1000s and RX340s.
A RTL V3 also can do multiple virtual receivers unlike the WJ and TT RX340 that only offer memories, I've had ten vrx up and operating with a lowly old pc and RTL V3.

Anyway, just some observations and wondering why rx boxen seem to be so overvalued compared to HAM rigs or similar or even greater performance and features.

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