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Arising from this post, I have just powered on my first RTL-SDR for the first time. And starting at the basement level, I have tuned into a local FM radio station and also the local weather feed, just to make sure everything works. 📡 📻

(And nope, I didn’t manage to build gqrx for Snow Leopard. I used a previously created binary which works on Snow Leopard.)

This totally whips.

Screen shot 2021-09-14 at 00.14.49.png
Local FM radio station

Screen shot 2021-09-14 at 00.45.18.png
Environment and Climate Canada

Screen shot 2021-09-14 at 01.53.58.png
Canadian Pacific Railway
 
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Arising from this post, I have just powered on my first RTL-SDR for the first time. And starting at the basement level, I have tuned into a local FM radio station and also the local weather feed, just to make sure everything works. 📡 📻

(And nope, I didn’t manage to build gqrx for Snow Leopard. I used a previously created binary which works on Snow Leopard.)

This totally whips.

View attachment 1830773
Local FM radio station

View attachment 1830774
Environment and Climate Canada

View attachment 1830779
Canadian Pacific Railway

Tonight, getting an ultra-hot signal from a nearby locomotive waiting to enter a rail yard — so hot, I can almost smell the sulphur-rich diesel:

Screen shot 2021-09-15 at 04.10.52.png

I’d share an audio sample, but gqrx crashes each time I try to record. This version doesn’t appear to allow the user to set a directory for making/saving audio recordings.

In any event, I’ve been able to listen to audio from both major railway carriers this evening, and the folks on each have totally different vibes. Despite getting signals this strong, I realize I’m still at the “welcome, new user! would you like a tutorial?” Clippy-stage of amateur radio, and some day I’ll look back wistfully at this post and laugh at my greenness. :)
 
Currently porting over the DGEN genesis emulator to Intel Tiger. I made a PowerPC build last year for Panther, but since it is for PowerPC it had to use the 100% C code core which really struggles on anything less then a high end G4.

The Intel build gets to use the assembly code core and seems to work perfectly on even the lowest end Intel macs. And a completely up to date emulator, on Intel Tiger, with Xbox 360 controller support using the https://tattiebogle.net/index.php/ProjectRoot/Xbox360Controller/OsxDriver driver seems long over due. It supports compressed rom files as well.

Next? SM64EX for Intel Tiger. Then PPCMC 7.2.6.

Really want to play some golden axe however ;)
 
Tonight, getting an ultra-hot signal from a nearby locomotive waiting to enter a rail yard — so hot, I can almost smell the sulphur-rich diesel:

View attachment 1831828

I’d share an audio sample, but gqrx crashes each time I try to record. This version doesn’t appear to allow the user to set a directory for making/saving audio recordings.

In any event, I’ve been able to listen to audio from both major railway carriers this evening, and the folks on each have totally different vibes. Despite getting signals this strong, I realize I’m still at the “welcome, new user! would you like a tutorial?” Clippy-stage of amateur radio, and some day I’ll look back wistfully at this post and laugh at my greenness. :)

Tonight, as I trawl the megahertz with the SDR on the A1261 running gqrx on 10.6.8 (did anyone see what I did there?), I decided to go low and low(er). What I got was a real mixed bag of fascinating, comforting, and also trash. For the first time, I tried a feature calling “direct sampling”, which made it possible with gqrx to pick up AM radio and some shortwave signals (using the rtl=0,direct_samp=3 setting). I was somewhat surprised by how weak local AM radio was, which may have something to do with my antenna setup.

Screen shot 2021-09-16 at 01.47.04.png

Getting the trash out of the way, I found a frequency (4.8401 MHz) which sounded like a possible repeater of either some TV, FM, or AM broadcast. The signal, which faded in and out, was just strong enough to decipher and it managed to get clear enough at times to parse what was being said. I listened for maybe 45 seconds when I could hear the dude on the mic (clearly some kind of radio talk show) started making inflammatory, revolting remarks about trans women, then segued instantly into some “new world order” spiel, followed by something-something about illiteracy, followed by some conspiracy theory that the pandemic was planned or something along those lines. About the only noteworthy thing about this geyser of garbage is he managed to do all of that in the span of about 120 seconds.

Soooo… I went on to the next find:

1631777349942.png

This one, at 56.860 MHz (the thin red bar, about 35 per cent in from the left) was also unidentifiable (ignore that bright beam on the right; that has to do with some harmonics with the crystal in the SDR, I think), but I was able to parse that it was playing Chicago’s “Make Me Smile” (I think just the 7-inch single, not the full, two-part version from the album), so that was fun.

1631777936090.png

Then, at 29.540 MHz, more music, some station, possibly also a repeater or echo, was playing hardcore-yacht pop, which is right up my alley: Player’s “Baby Come Back”, followed by Kenny Loggins’ “This Is It” (with Michael McDonald), but when voice-over emerged, it was too distorted beyond my guessing it was some syndicated show from the U.S. But hearing yacht pop on a distant radio station in the middle of the night always warms my heart.

Finally, the surprise of the night, just before shutting it all down.

1631778714060.png

After switching back to standard, rtl=0 mode, this signal at 133.4 MHz, took me by surprise — both because I wasn’t expecting it and I wasn’t expecting it to be so strong: a pilot from a jet aircraft, either taxiing for takeoff or just airborne, saying good-night to the tower. I only caught the very end of it, but it was crystal-clear, much like the railway stuff the previous night.

Aaaaand I think this will be the last time I bore y’all and derail this thread any further with stuff which probably belongs on a radio hobbyist forum which isn’t MR. :)
 
That's more pixels than the original LG UltraFine 4K.
Yep. I’m going to keep my UltraFine though. :)

is the HD Graphics 3000 capable of 4096 width or is it limited to 4095?
I’ll test this. :) BTW for some reason SwitchResX says the monitor‘s max pixel clock is 270 MHz on the HD 3000 so I can only get, like, 25 Hz at native resolution (CVT-RB). It does accept this though. I’ll see if that can be overridden.
 
Yep. I’m going to keep my UltraFine though. :)

I’ll test this. :) BTW for some reason SwitchResX says the monitor‘s max pixel clock is 270 MHz on the HD 3000 so I can only get, like, 25 Hz at native resolution (CVT-RB). It does accept this though. I’ll see if that can be overridden.
I would like to see an EDID preferably from AGDCDiagnose if possible. There doesn't seem to be one for this display at https://github.com/linuxhw/EDID or https://github.com/bsdhw/EDID
 
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I would like to see an EDID preferably from AGDCDiagnose if possible.
I have attached the complete output of AGDCDiagnose -a. I'm using a DisplayPort connection to a Radeon RX 460 which also has a Dell UP2715K connected to it. I can supply the output when using HDMI too if desired. :)
 

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I have attached the complete output of AGDCDiagnose -a. I'm using a DisplayPort connection to a Radeon RX 460 which also has a Dell UP2715K connected to it. I can supply the output when using HDMI too if desired. :)
Yes, HDMI would be interesting as well. HDMI EDID is usually much different than DisplayPort EDID.
 
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I have attached the complete output of AGDCDiagnose -a. I'm using a DisplayPort connection to a Radeon RX 460 which also has a Dell UP2715K connected to it. I can supply the output when using HDMI too if desired. :)
The display is DisplayPort 1.4 but it's limited to HBR2 link rate so it can't do 10bpc RGB HDR at 60Hz unless DSC or 4:2:2 is supported.
What version of macOS are you using? I think you need Catalina to know if the display supports DSC.
The DisplayPort EDID does mentions RGB, 4:4:4, and 4:2:2 support.
ADCDiagnose says you are running at RGB 8bpc SDR. Is HDR an option in macOS? What happens if you select that?

What iMac model do you have? I haven't seen the EDID for your iMac display before.

The specs page says HDMI 2.0 can do full rez only up to 50Hz. But for 8bpc RGB, a custom timing should be able to do 56-57Hz. With 4:2:0, a full 60Hz should be possible. The DisplayPort EDID doesn't mention 4:2:0.

The EDID for the DisplayPort connection says the range is 48-75 Hz, 45-180 kHz, max dotclock 690 MHz but there exists some 30Hz timings.

The User Guide doesn't contain much info.

As for HD Graphics 3000 limits, maybe you're limited to DisplayPort 1.1? Does AGDCDiagnose give any info for that with the latest OS that you can run? If not, then Linux.
https://github.com/atseanpaul/dpcd_parser
https://github.com/tompreston/parse_dpcd
 
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What version of macOS are you using?
Mojave

Is HDR an option in macOS?
Would that be in System Preferences > Displays? Nothing there.

What iMac model do you have?
Late 2015 21.5" 4K (iMac16,2). It has the Iris Pro 6200; the RX 460 is connected via Thunderbolt 2 because the Iris cannot handle the Dell UP2715K - at least on Mojave.

The EDID for the DisplayPort connection says the range is 48-75 Hz, 45-180 kHz, max dotclock 690 MHz but there exists some 30Hz timings.
The pixel clock for the 3840×2560@30Hz timing is much higher than for CVT-RB's timing. All other timings follow CVT-RB though. I wonder what's going on there.

As for HD Graphics 3000 limits, maybe you're limited to DisplayPort 1.1?
Shouldn't DP 1.1 allow for 360 MHz pixel clock though? I might have gotten 3840×2160@40Hz to work on the HD 3000 but would have to retry that to be sure (it might have been another machine/GPU after all).
 
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Mojave
Would that be in System Preferences > Displays? Nothing there.
I think you need Catalina to see the High Dynamic Range option in the Displays preferences panel.

Late 2015 21.5" 4K (iMac16,2). It has the Iris Pro 6200; the RX 460 is connected via Thunderbolt 2 because the Iris cannot handle the Dell UP2715K - at least on Mojave.
Right. Apple tech specs say that iMac can only connect one external display. The Dell requires two connections for 5K60.

The pixel clock for the 3840×2560@30Hz timing is much higher than for CVT-RB's timing. All other timings follow CVT-RB though. I wonder what's going on there.
True. That timing has very large horizontal front porch, sync, and back porch. Don't know why.

Shouldn't DP 1.1 allow for 360 MHz pixel clock though? I might have gotten 3840×2160@40Hz to work on the HD 3000 but would have to retry that to be sure (it might have been another machine/GPU after all).
True. There may be a pixel clock limit in the Apple driver. 270MHz is just enough for a 2560x1600 60Hz display (269 MHz).
 
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Apple tech specs say that iMac can only connect one external display.
They're incorrect. :) I've run two external displays, in addition to the iMac's display, from the Iris Pro 6200. Dell P2415Q (3840×2160 60 Hz) and LG UltraFine 4K (4096×2304 48 Hz). I didn't save the System Profiler screenshot but it worked fine. Connecting the UP2715K's two cables to the iMac gave no picture on it. I don't remember what happened to the iMac's display.

Interestingly, the iMac display's EDID reveals it needs a 605 MHz pixel clock for its native 4096×2304 60 Hz timing - almost, but not quite, identical to CVT-RB's if I'm interpreting the EDID correctly. Broadwell-H can have a Core Display Clock of up to 675 MHz (source), explaining why that works. Connecting the UltraFine 4K to the iMac, however, doesn't allow 4096×2304 60 Hz (its mode requires a 593 MHz pixel clock IIRC) - it defaults to the 48 Hz mode, suggesting the iMac's "external" DisplayPort outputs are limited to less than 593 MHz (576? 540?).

There may be a pixel clock limit in the Apple driver.
I just tried an Asus MG24UQ (4K60) display and pixel clock also shows up as 270 MHz max on the HD 3000. Tried both DP 1.1 and 1.2 modes. So, that 360 MHz limit must have come from another GPU - a Radeon HD 6870 or GeForce 320M (which can do 4096×2304@30Hz, i.e. is definitely not limited to 270 MHz).
 
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Not sure if my 2010 Mac Pro counts as an early Intel Mac but I just upgraded it from a single processor to dual processor. Finally the price of dual CPU trays have reached a reasonable level I decided to pull the trigger. Seeing 24 thread in Activity Monitor was pretty cool. That must have been something back in the day when these were currently on sale.
 
They're incorrect. :) I've run two external displays, in addition to the iMac's display, from the Iris Pro 6200. Dell P2415Q (3840×2160 60Hz) and LG UltraFine 4K (4096×2304 48Hz). I didn't save the System Profiler screenshot but it worked fine. Connecting the UP2715K's two cables to the iMac gave no picture on it. I don't remember what happened to the iMac's display.
That's interesting. The UP2715K only needs 483.25MHz for each connection to get 5K60. It also has a 5K30 mode using two connections of 238.25MHz but I don't think macOS exposes both options. I think it's not until macOS supported the XDR (Catalina) where you can have an mtdd file with multiple back and front end timings but I've never tried getting a 5K30 mode to work.
The first macOS with a mtdd for the UP2715K is Yosemite. It hasn't changed since then (except audio was added in El Capitan).
ls /Volumes/*/System/Library/Displays/Contents/Resources/Overrides/*/*.mtdd

Interestingly, the iMac display's EDID reveals it needs a 605 MHz pixel clock for its native 4096×2304 60Hz timing (which is almost, but not quite, identical to CVT-RB's if I'm interpreting the EDID correctly). Broadwell-H can have a Core Display Clock of up to 675 MHz (source, pages 104/105) which explains why this works. Connecting the UltraFine 4K to the iMac, however, doesn't allow running it at 4096×2304 60Hz (which only requires a 593 MHz pixel clock IIRC) - it defaults to the 48Hz mode, suggesting the iMac's "external" DisplayPort outputs are limited to less than 593 MHz. (576? 540?)
Page 106 has the pixel clock info. So the iMac can do up to 675 MHz but only at 6bpc or 8bpc (macOS doesn't support 6bpc).
AGDCDiagnose doesn't do device dumps for the Intel GPUs so we can't see what pixel format the built-in display is using.

The original LG UltraFine 4K includes these modes:
1920x1080@60.000Hz 66.660kHz 133.32MHz
2560x1440@60.000Hz 88.860kHz 234.59MHz
3360x1890@60.000Hz 116.640kHz 401.24MHz
3840x2160@30.000Hz 65.730kHz 257.66MHz
3840x2160@59.999Hz 133.319kHz 522.61MHz
3840x2160@59.999Hz 133.319kHz 522.61MHz
4096x2304@29.999Hz 70.108kHz 292.77MHz
4096x2304@47.999Hz 113.135kHz 472.45MHz
4096x2304@59.999Hz 142.198kHz 593.82MHz

I just tried an Asus MG24UQ (4K60) display and pixel clock also shows up as 270 MHz max on the HD 3000. Tried both DP 1.1 and 1.2 modes. So, that 360 MHz limit must have come from another GPU - either a Radeon 6870 or GeForce 320M.
I'm thinking you need some pixel clock patches for the Iris Pro 6200 and HD 3000. There's some patches at https://github.com/Floris497/mac-pixel-clock-patch-V2.
They are not documented. I would look at the disassembly before and after a patch to see what numbers they are changing.
The IOKit patches (for El Capitan and earlier) modify IOKit.framework.
The CoreDisplay patches (For Sierra and later) modify CoreDisplay.framework.
Lilu/WhateverGreen can do pixel clock patch on CoreDisplay without modifying CoreDisplay. https://github.com/acidanthera/WhateverGreen
https://github.com/acidanthera/What...telHD.en.md#hdmi-in-uhd-resolution-with-60fps
I made a patch that modifies VGA adapter max pixel clock. It modifies AppleIntel*Framebuffer kernel extensions.
https://github.com/Floris497/mac-pixel-clock-patch-V2/issues/323
 
Been using the MacPro to charge phones today…

On the left is the HTC Touch Pro I bought earlier this year. I restored it to a September 2012 backup. I had this phone from May 2009 to September 2012. It's heavily modified. The original was sent off to someone who needed it.

The 3GS I also got earlier this year. Replaces the 3GS I gave to a member here who was moving and needed a phone. Originally I had gotten it for Christmas 2011. I used the 3GS to learn iOS. From December 2011 to September 2012 I was carrying both the 3GS and my Touch Pro.

The iPhone 5 is the third replacement of the iPhone 5 I got in September 2012. I was fortunate in early 2017 that Apple gave me a carrier choice (I chose Verizon) and this Sprint model iPhone 5 became fully unlocked. It was being used as my secondary phone until I replaced that with my 6s+.

2021-09-18 20.32.06.jpg
 
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