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Good & reasonable HDMI scaler: Extron RGB-HDMI 300(A)

cheesestraws

Well-known member
At @Trash80toHP_Mini's request, a thread about the HDMI scaler I found myself using to do vintage Mac stuff on a modern screen.  It works, at least for me, really well and I'd recommend it to other folks as well.  It is also not *that* expensive.

The model is Extron RGB-HDMI 300 or 300 A.  I spent about £55 on mine from eBay UK, second-hand of course.  At time of writing the cheapest on eBay US looks like about $35, so I may have slightly overpaid, but most seem to be $70ish.  This, for me, is pretty reasonable given that I am going to use it a lot.  The usual chancers are trying to sell them for hundreds, and I get the impression this may have been quite pricy new.  A number of the cheaper ones don't seem to come with a power supply brick.  Do not be put off.  It just takes 12v, and the pins at the back are helpfully labelled with polarity, so I just knocked a power cable up with a couple of female header cables and a 12v power supply from the random wires drawer.

It has a VGA-style input at the back.  I say VGA-style because I tried it with traditional Apple resolutions and it worked fine, as well as with PC resolutions.  In fact, it seems remarkably un-picky.  My Quadra is using a standardish 10-dip pin adapter pretending to be a 21" screen at 1152x870, and all I needed to manually set was the number of horizontal pixels in total and in the active area, and tweak the phase knob until it stopped shimmering.

A feature I suspect will be useful for many people is that you can set the image size and position on the output, it doesn't just automatically fill the screen.  So, if your screen's native resolution matches one of its output resolutions, you could set the output size to the same as the input size and center it in the screen, and you would get 1:1 pixels where 1 Mac pixel is 1 on-screen pixel.  My own screen does not have a native resolution matching any of its output resolutions, so I can't speak to how well that works, but it is possible.

In terms of output, it will output up to 1900x1200, but my screens are 16:9, so I ended up using 1920x1080.  This isn't the native resolution of my screen but even so the result is pretty decent (I suppose the screen must also have a reasonably decent scaler).

Here's a photo.

61022155833__C8A6F61A-87EA-40AA-B8D5-3B82FE2A2628.JPG

 

Trash80toHP_Mini

NIGHT STALKER
BOOM! $51 shipped!  [:D] Thanks so much. eBay search "extron scaler" as "Extron RGB-HDMI 300" yielded one of those $199 jobs. Howevert it's the "A" version which apparently handles audio?

 

cheesestraws

Well-known member
Yeah, mine is the -A one.  They both seem to come up reasonably cheaply, the -A was what was available cheap in the UK while I was looking.  And yes, the -A handles audio and squirts that out the HDMI connector too.  According to the manual, that's the only difference between the 300 and the 300-A.

 

Trash80toHP_Mini

NIGHT STALKER
Got this one: https://www.ebay.com/itm/Extron-RGB-HDMI-300-RGB-to-HDMI-Scaler-with-power-supply-Tested-Working/274350537800

Just snagged this one as it's amazingly flexible for the DVI panels on my workstation next to the TelCo rack: https://www.ebay.com/itm/254535437124

***** NOT VGA***** I'm hoping the inputs will adapt easily to Mac DA-15->BNC cables (RGB+) If not, it's way too cool a toy to pass on anyway. Dying to see if it syncs with my SE/Radius16/TPD card setup.  [}:)]

s-l1600.jpg.946982351bea905929505db205d5202b.jpg


Scaling-n-Viewporting.JPG

https://data2.manualslib.com/pdf4/82/8117/811641-electrosonic/imagestar_hd.pdf?6516430477b29fa08347cd8231a8caca

TLDR manual mentioned using multiple units. My dream scaler setup would throw multiple (scalable, positionable) active desktops on a 1440p panel.

 
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Trash80toHP_Mini

NIGHT STALKER
Likely not, your setup looks to be almost the same as mine. I peeked at the manual and noticed the "RGB" input is VGA and that a standard VGA to BNC-RGBHV cable can be used to adapt input. If so, this box too may be the silver bullet for getting early Radius FPD and TPD Cards up and running on HDMI panels?




 

Trash80toHP_Mini

NIGHT STALKER
Time to read the docs to see what kind of adjustments are available, but not bad for a throw it all together really fast and see what happens test.

Extron_Scaler-Take1-RadiusTPD-SE-to-HDMI-1080p.JPG

42" 1080p TV syncs, saying the Extron RGB Scaler is feeding it 1024 x 768 @60Hz From the Radius Two Page Display Card in the SE. It's a start! :approve:

 

Trash80toHP_Mini

NIGHT STALKER
We've got a start, Dunno about the banding,the linked TPD thread has very relevant info posted by @Gorgonops

Radius TPD   1152x870   71Hz Vertical / 66kHz Horizontal

Scaled          1024x768   60Hz

The image is a little fuzzy, could be caused by interpolation of 1152x870 scaled into the 1024x768 VGA standard? G said most LCD panel scalers won't sync to anything but VGA standard resolutions. I would think that may indicate more flexibility in this scaler as it converts oddball Mac to aVGA standard. Have you found a 1:1 mode that "picture frames" lower resolutions within 1080p? The Column/Letterbox/bumped to top of screen makes me think that could well be a feature of this Extron RGB - HDMI scaler?

I have much higher hopes for the ELECTROSONIC Imagestar HD. Because it can break a single image into outputs for extending panels, maybe it will "Pictureframe" an oddball resolution onto a single screen at 1:1? Gotta identify the power connector, find or buzz the spec for its connection pinout to the board.

 

cheesestraws

Well-known member
The image is a little fuzzy, could be caused by interpolation of 1152x870 scaled into the 1024x768 VGA standard... The Column/Letterbox/bumped to top of screen makes me think that could well be a feature of this Extron RGB - HDMI scaler?


OK.  Here's how you do this.   I did say it could in the first post but I didn't give instructions.

  1. Send some video into the scaler
  2. Press 'Menu', go down to 'Output Configuration' (using the up/down knob).  Press 'Enter'.  Press 'Enter' again to set the resolution and then use the left/right knob to set the resolution to the native resolution of the screen, or at least something with the right aspect ratio.  If this isn't right, obviously nothing else will be.  The menu timeout is very short, beware.
  3. You now need to set the horizontal resolution, because it can't autodetect that.  Press 'Menu' again and go down to 'Input configuration'.  Press Enter.  Go down to 'TOT PIXEL PHS', and press Enter.  Use the left/right knob to set the total pixel width.  For colour 1152x870 this is 1456.  Press Enter.
  4. Still in the Input Configuration menu, go down to 'ACTIVE' and press Enter.  Use the left/right knob to set this to 1152.  Check that V is showing 870.
  5. Now the scaler knows what resolution it's getting in and what resolution it's outputting.  Now we can adjust the size/position of the image.  Go to the Picture Controls menu, go down to Size and press Enter.  Use the up/down arrow knob to set the height to 870 and the width to 1152.
  6. Now go to Position in that menu and fiddle around until it's in the middle.  Do the arithmetic yourself :)
  7. Finally, you can fiddle with the PHS setting in Input settings to alter the point in each pixel where sampling takes place: this is probably very video card specific.  For my Q950 at that resolution, a PHS value of 9 was very much the best, but you just have to fiddle with this until it works.
 

Trash80toHP_Mini

NIGHT STALKER
Many thanks, this should give me a bit of fun after work tonight. Gotta find my SD/FDHD board so it will boot off the 7.1 HDD from the SE/30 testbed.

The ELECTROSONIC Imagestar HD has two VGA and two BNC inputs so that'll be some fun when I have SUN/MON off. I have a bazillion and three cables, some for things I don't even own, but not a single BNC<->BNC cable, go figure! ::)  

Here's a strange one, has anyone seen this connector before, specs? From the diagram it looks like the three pins are all 12V and the shield is ground?

Electrosonic-Scaler-Power-Connection.JPG

I've never seen anything remotely like this. May need a dedicated Lounge thread for this one, very strange.

 

cheesestraws

Well-known member
Many thanks, this should give me a bit of fun after work tonight. Gotta find my SD/FDHD board so it will boot off the 7.1 HDD from the SE/30 testbed.
Let me know how it goes.  I'm curious.

I've never seen anything remotely like this. May need a dedicated Lounge thread for this one, very strange.
Yeah, separate thread for that sounds good.  No idea what that is.

 

cruff

Well-known member
I found an RGB-HDMI 300A at https://www.surpluscrestron.com for $53 delivered. It was a pull from service, and was missing the connector block for the power. I believe a connector like this https://www.digikey.com/product-detail/en/molex/0395000002/WM7732-ND/1280583 will work, I haven't yet ordered one to verify, but I have a four position connector block like that on my Keysight power supply and the dimensions are correct.

I hooked it up today to my VAXstation with a 5 coax to VGA cable and it worked nicely with my Sony TV. I haven't tried it with my IIgs yet, but found a link about how to do it at http://www.apple2faq.com/knowledgebase/iigs-to-hdmi-using-an-extron-rgb-hdmi-300a/

 
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cheesestraws

Well-known member
That looks plausible.  The one I have here has one of those in its serial port (though with more ways, obviously).

I hooked it up today to my VAXstation with a 5 coax to VGA cable and it worked nicely with my Sony TV
You can't just tease us like this without pics ;-) .

 

cruff

Well-known member
Ok, all I have is a crappy phone picture, I didn't get my good DSLR out to do a proper job. The moire pattern was caused by the phone sensor, and it doesn't look like that at all. The picture was quite good once I disabled the auto image scalling and increased the brightness setting. My VAXstation 4000/60 has a 1280x1024 8bit graphics card in it that outputs RGB with composite sync on G. I've ordered that connector for the power input, it should be here next week. My power supply said the 300A was drawing 0.83 A at 12 V while the display was active.

IMG_1671.JPG

 
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blusnowkitty

Well-known member
Here's a strange one, has anyone seen this connector before, specs? From the diagram it looks like the three pins are all 12V and the shield is ground?

I've never seen anything remotely like this. May need a dedicated Lounge thread for this one, very strange.
Couldn't tell you what the connector itself is called, but I have seen the exact same thing on Epson receipt printers: https://www.ebay.com/itm/Genuine-Epson-TM-H6000III-TM-H6000IV-TM-U220P-M235A-24v-Power-Supply-Adapter/254482520289

Mind, the pinout between this scaler and the Epson printer is likely completely different - I know the Epson printers need 24vdc. Since there's no hard and fast rule that says Connector ABC MUST be wired XYZ, you'll probably have to do some probing around on the board to see what you can find.

 
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