121
Equipment / Re: Construction of Shortwave beacon
« on: July 20, 2021, 1712 UTC »
If cooling is a concern, construct the enclosure out of a diecast aluminum box. That will be more than adequate for this power level.
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Shortwave Pirate Radio In North America And Around The World, And Other Signals That Go Bump In The Night
We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations.
Always consult with the appropriate authorities if you have questions concerning what is permissible in your locale.
I would wonder if you go to that length, whats to keep someone (with lots of money) from floating an entire building an using that as an antenna? Maybe a watertower?
During WWII, many domestic AM's that were considered "essential" built fortifications around their tower bases to keep the enemy from shooting out the insulators and bringing the tower down.
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122
North American Shortwave Pirate / Re: X-FM 6285 AM 0238 UTC 11 JUL 2021
« on: July 11, 2021, 1657 UTC »
Thanks all for the reports!
Aircheck https://drive.google.com/file/d/1DXAuJt_6zZPXzBtsPWDMTC3TJRqp5wjA/view?usp=sharing
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Aircheck https://drive.google.com/file/d/1DXAuJt_6zZPXzBtsPWDMTC3TJRqp5wjA/view?usp=sharing
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123
The RF Workbench / Re: ICOM AD-55 power supply output voltage adjustment
« on: July 08, 2021, 1716 UTC »
Doesn't surprise me. I've seen more than a few questionable designs come out of icom over the last few decades. From filter boards that zorch and smoke, to things like this...no thanks.
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124
The RF Workbench / Re: Stretchyman “40W TX” Failure Investigation and Remediation
« on: July 08, 2021, 1542 UTC »
I guess I should have read this document Sooner.
Some thoughts;
I have lost a handful of SiC devices over the last few years while building my transmitter, and usually they failed because of my assumptions in design leading to a few deficiencies. One thing I did find during my research is that most of the failures occurred during drive loss events. This seems to be evident in the transient nature of the waveforms you observed. Most DDS devices produce a DC output when not programmed, and this is specified in the Analog Devices datasheet for the AD9850. I think Stretchy was using a 9800 series DDS in his devices, mainly for cost reasons. Until the program is loaded into the DDS, it will latch the output of the PA on, causing an overcurrent failure of the transistor. My solution was to add a drive loss protection circuit, and I have not lost another device since.
The later versions of his transmitters I noted the elimination of the modulation transmitter, and instead feeding the PA directly from the modulator. This may well have solved the problem, as the modulator has overcurrent sensing and protection built in.
+-RH
Some thoughts;
I have lost a handful of SiC devices over the last few years while building my transmitter, and usually they failed because of my assumptions in design leading to a few deficiencies. One thing I did find during my research is that most of the failures occurred during drive loss events. This seems to be evident in the transient nature of the waveforms you observed. Most DDS devices produce a DC output when not programmed, and this is specified in the Analog Devices datasheet for the AD9850. I think Stretchy was using a 9800 series DDS in his devices, mainly for cost reasons. Until the program is loaded into the DDS, it will latch the output of the PA on, causing an overcurrent failure of the transistor. My solution was to add a drive loss protection circuit, and I have not lost another device since.
The later versions of his transmitters I noted the elimination of the modulation transmitter, and instead feeding the PA directly from the modulator. This may well have solved the problem, as the modulator has overcurrent sensing and protection built in.
+-RH
125
Huh? / Re: Windows 11? Why???
« on: July 07, 2021, 1505 UTC »
I gave up on MS years ago. I've been running Linux in some flavor for over a decade. Its free, and has it quirks, but does what I need. Did I mention its free? 
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126
Propagation / Re: VHF Airplane Scatter
« on: June 09, 2021, 2244 UTC »
If you monitor empty FM channels (is there really such a thing anymore 
) you will hear this quite a bit.
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) you will hear this quite a bit.+-RH
127
General Radio Discussion / Re: Short Commercial AM Broadcasting Antennas
« on: June 09, 2021, 2230 UTC »
You may hear more about this in the future. I read recently that the commission is considering relaxing the rules on AM antenna efficiency in order to provide stations more latitude with regard to finding replacement tower facilities for stations displaced by urban sprawl and gentrification. Usually you have to have a full proof done by measuring field strength at many points and requesting an operating variance, or something to that effect.
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128
Amateur Radio / Re: RF Exposure Standards go into effect on May 3, 2021, including Amateur Radio!
« on: May 23, 2021, 2200 UTC »
Lots of luck enforcing any of this....
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129
North American Shortwave Pirate / Re: Mix Radio Int. 6865 USB 2352 UTC 15 May 2021
« on: May 16, 2021, 0211 UTC »
Pretty good copy here of U2's "I Will Follow". About S6 here on the MW vertical.
0229 New Order "Blue Monday"
0232 MRI "turn it up" ID, intowhat sounds like the Pretenders Talking Heads 'Take Me To The River'
0242 David Bowie 'China Girl'
0258 Depeche Mode 'Personal Jesus' No real change in signal over the last 45 minutes.
0300 MRI ID into Boy George? Culture Club "I'll Tumble 4 Ya'
0307 INXS 'Need You Tonight' Seems a good night. Got Cevapi off the grill, cold beer, and tunes on the radio
0313 Tears for Fears 'Mad World'
0323 The Psychodelic Furs 'Love My Way'
since we're doing 80's How about The Church 'Under The Milky Way?
0327 Peter Gabriel 'Sledgehammer'
0335 MRI Request ID. into The Church 'Under The Milky Way'! Thanks bud
FWIW, frequency is dead on via the SDR tonight, as always 6865 KHz USB.
0340 MRI 'It Just Rocks' ID, into B52's 'Private Idaho', another one of my favorites!
0344 MRI phaser type ID into The Polecats 'Make a Circuit With Me'
0347 David Bowie 'Lets Dance' (Radio Edit) Another good one!
Thanks for the tunes!
+-RH
0229 New Order "Blue Monday"
0232 MRI "turn it up" ID, into
0242 David Bowie 'China Girl'
0258 Depeche Mode 'Personal Jesus' No real change in signal over the last 45 minutes.
0300 MRI ID into Boy George? Culture Club "I'll Tumble 4 Ya'
0307 INXS 'Need You Tonight' Seems a good night. Got Cevapi off the grill, cold beer, and tunes on the radio
0313 Tears for Fears 'Mad World'
0323 The Psychodelic Furs 'Love My Way'
since we're doing 80's How about The Church 'Under The Milky Way?
0327 Peter Gabriel 'Sledgehammer'
0335 MRI Request ID. into The Church 'Under The Milky Way'! Thanks bud
FWIW, frequency is dead on via the SDR tonight, as always 6865 KHz USB.
0340 MRI 'It Just Rocks' ID, into B52's 'Private Idaho', another one of my favorites!
0344 MRI phaser type ID into The Polecats 'Make a Circuit With Me'
0347 David Bowie 'Lets Dance' (Radio Edit) Another good one!
Thanks for the tunes!
+-RH
130
General Radio Discussion / Re: Explosives "Resistant"/ Hardened Antennas
« on: May 12, 2021, 1832 UTC »I believe that the Israelis had a "hardened" antenna (if I recall correctly) for AM broadcast. It consisted of heavy steel I beams welded in series stood off on large insulators , very close to the ground (6' up ?) .There may have been protective earthen dikes around it as well.
I would wonder if you go to that length, whats to keep someone (with lots of money) from floating an entire building an using that as an antenna? Maybe a watertower?
During WWII, many domestic AM's that were considered "essential" built fortifications around their tower bases to keep the enemy from shooting out the insulators and bringing the tower down.
+-RH
131
Equipment / Re: Looking for suggestions for a circa 4100 kHz directional antenna
« on: May 05, 2021, 1856 UTC »
Some folks have had good luck with the D-Kaz on lower frequencies, especially medium wave. Perhaps this could be scaled down slightly for 4 MHz?
http://durenberger.com/wp-content/uploads/2019/11/D-KAZ-COOKBOOK-Pt1.pdf
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http://durenberger.com/wp-content/uploads/2019/11/D-KAZ-COOKBOOK-Pt1.pdf
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132
Equipment / Re: MFJ-209C for medium wave tests?
« on: May 01, 2021, 1512 UTC »
I still have my RigExpert Zero, which I bought on your recommendation Chris. I bought the 35 Zoom simply so I didn't have to keep dragging a laptop to the base of the antenna every time I was in the field setting up for a show
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133
Equipment / Re: MFJ-209C for medium wave tests?
« on: May 01, 2021, 0123 UTC »
I never liked the MFJ analyzers; too easy to damage by inadvertent static, etc. I bought a rigexpert AA-35 Zoom last year, couldn't be happier, and it goes down to 60 KHz. And yes, I have used it on a psudo-part15 station.
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134
General Radio Discussion / Re: Objection filed against application for DRM SWBC license
« on: April 23, 2021, 2001 UTC »
With the changing of the guard at the commission, this may have the desired effect. It is rather satisfying to read such roasting in legalese
Maybe all the racket on 43 meters will go away soon, just in time for the coming of the new cycle.
+-RH
Maybe all the racket on 43 meters will go away soon, just in time for the coming of the new cycle.
+-RH
135
North American Shortwave Pirate / Re: UNID 4180 USB 0130 UTC 20 Apr 2021
« on: April 20, 2021, 0200 UTC »
4180 KHz USB 3KHz audio good reception with a few shallow fades.
0157 Alex Mattson feat. Solamay 'UFO'
0201 UFO 'Cherry'
0204 UNID mumble rap track
0206 Goats screaming overan UNID rock track UFO 'Too Hot To Handle'
0210 OP, sounding very much like DJ Dickweed. Into a nebulous slow paced track.
0213 'Goat Hearder Radio' ID, OP talking about first class phone.
0218 OP "No, no, no, I'm not dickeed, I'm his evil twin!" into song "Dead Puppies"
0220 'I am the witch doctor'
Thanks for the show!
+-RH
0157 Alex Mattson feat. Solamay 'UFO'
0201 UFO 'Cherry'
0204 UNID mumble rap track
0206 Goats screaming over
0210 OP, sounding very much like DJ Dickweed. Into a nebulous slow paced track.
0213 'Goat Hearder Radio' ID, OP talking about first class phone.
0218 OP "No, no, no, I'm not dickeed, I'm his evil twin!" into song "Dead Puppies"
0220 'I am the witch doctor'
Thanks for the show!
+-RH