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Shadow detail/gamma enhancement for the analog sources  

post #1 of 492
Thread Starter 
It's designed! A circuit for enhancing shadow detail in analog sources. It will do the same thing as the circuit in an earlier thread except this one doesn't have to be direct coupled with the back porch at zero volts. This one does require a horizontal or composite sync input along with the RGB video.

The DC restore circuit took more time than I thought it would and was more difficult, too. The availability of video/sync processing chips seems to be shrinking. No more LM2202s out there. This is probably better because all the parts can be had from Newark, Mouser, etc. They're cheap, too.

The original thread:

http://www.avsforum.com/avs-vb/showt...1&page=1&pp=30
LL
LL
LL
post #2 of 492
Thread Starter 
The rest of the schematic.

If anyone wants the Orcad files, yell. I'll be happy to send them. You can go to the Orcad web site and download a demo of their software. It works but restricts you to small designs.
LL
LL
LL
post #3 of 492
Let me be the first to say congratulations, tse!!!

Ericglo
post #4 of 492
Now how does that saying go "Build it and they will come."
post #5 of 492
Thankyou tse.


Since I'm currently in Europe, I am trying to track down a Yamakawa 375, which I understand is a Momitsu v880 clone, with a better built case (and remote). Has anyone scoped the analog RGB from a sigma EM8500 based dvd player to determine if tse's original ESD circuit can be added while doing an output stage/ BNC mod i.e. the back porch is at zero volts?

Cheers,

John
post #6 of 492
Quote:
Originally Posted by misohorny
Thankyou tse.


Since I'm currently in Europe, I am trying to track down a Yamakawa 375, which I understand is a Momitsu v880 clone, with a better built case (and remote). Has anyone scoped the analog RGB from a sigma EM8500 based dvd player to determine if tse's original ESD circuit can be added while doing an output stage/ BNC mod i.e. the back porch is at zero volts?

Cheers,

John
That circuit would be a serious help for the Momitsu (as well as any other source). It would be nice to have it as an external device before the projector, as well as, an input card version for the well known CRT's.

So far, it seems to be the cure for that linear gamma problem that's commom with most CRT projectors.
post #7 of 492
How hard would it be to get boards made? I'm comfortable sourcing components, soldering, and sticking stuff in a case, but I'm clueless on where or how to get PCB's made. Wasn't there a sort of "automated" prototyping/small-quantity site where you could upload files and get back finished boards pretty reasonably? I'd love to try one of these, but I'm on a pretty strict budget these days.

Thanks for your hard work tse - I can't wait to see how this works with my own eyes.

SC
post #8 of 492
MP, do you happen to know if the Momitsu's have a non-0V porch? I measured mine and it sure looked like 0V to me, but I'm no expert at reading video waveforms.
post #9 of 492
Quote:
Originally Posted by ecrabb
How hard would it be to get boards made? I'm comfortable sourcing components, soldering, and sticking stuff in a case, but I'm clueless on where or how to get PCB's made. Wasn't there a sort of "automated" prototyping/small-quantity site where you could upload files and get back finished boards pretty reasonably? I'd love to try one of these, but I'm on a pretty strict budget these days.

Thanks for your hard work tse - I can't wait to see how this works with my own eyes.

SC


Four layer, solder mask and silkscreen rapid turn shop:
http://www.expresspcb.com/ExpressPCBHtm/Costs.htm
http://www.expresspcb.com/ExpressPCBHtm/Specs.htm

They've got their own downloadable schematic and routing software.
I'm taking delivery of some of their "Production" series 2 layer boards this week for a work project. I'll let you know how the quality works out.
post #10 of 492
Hi tse,
Good work,
So have you built some boards and tested this on a pj. Which pj did you test it on and how much of an improvement did you notice.
post #11 of 492
Quote:
So far, it seems to be the cure for that linear gamma problem that's commom with most CRT projectors.
Mike: curious what you mean by this? I think some of the digital guys have been trying to emulate the linear tail, because I believe it's written into the standards now.
post #12 of 492
Wow, this looks fab! tse any ideas on how much bandwidth these circuits can handle?

Jon
post #13 of 492
Quote:
Originally Posted by ChrisWiggles
Mike: curious what you mean by this? I think some of the digital guys have been trying to emulate the linear tail, because I believe it's written into the standards now.

Chris, You mean to say you've been a member since 2002 and you haven't noticed the number of threads where members with CRT projectors have been frustrated when, having calibrated their projectors in every way possible, they were still unable to obtain satisfactory black detail (linear gamma). The most likely reason I've read posted being the somewhat unpredictable CRT tube light output at low level, compounded by the effect of wear.
It would seem you have been spreading yourself too thin, contributing as you do so much to the digital projector forums as well.

For research purposes could you tell me which digital projector you have been watching lately? It would help when I collate the evidence that proves my theory that watching digital projectors causes psychosis.

Cheers,

John
post #14 of 492
Great stuff. So, is somebody going to make these? I'll just throw out that if you are looking for somebody to hand build some maybe moome would be a good person for it. I liked the transcoder I bought from him and he seems to have done some other good stuff.

I know at least one person who I think would be interested in this for a CRT and I would like to see the results.

--Darin
post #15 of 492
Nice work tse.

Has anyone already created a bill of materials with component pricing and sources?
post #16 of 492
Good idea Darinp2.

I think tse has done a brilliant job, and single handedly. He has provide the details, for those of us who enjoy the thrill of DIY, and if he partners with someone to manufacture these modules he is also catering to the "sell me one" members. With the detail made public improvements may come more quickly, although tse seems to be more than capable, solo.

John
post #17 of 492
Quote:
Mike: curious what you mean by this? I think some of the digital guys have been trying to emulate the linear tail, because I believe it's written into the standards now.
The linear tail is spec'd for Rec.709 gamma. I’ve not seen it spec’d (or desired?) for degamma (the display). Seems the Rec.709 degamma targets displays @ 2.5. for an overall 1.13 Have you seen the standards mention it in respect to displays? (degamma)

Dave
post #18 of 492
Hi Darin,

Actually I've included the tse circuit in my transcoder design which will be on the new Moome card, but only for the transcoder section not the HDMI section.
post #19 of 492
Quote:
For research purposes could you tell me which digital projector you have been watching lately? It would help when I collate the evidence that proves my theory that watching digital projectors causes psychosis.
barco 808. last time i checked it was a crt. but maybe i should check again. har...
post #20 of 492
Thread Starter 
Quote:
Originally Posted by ecrabb
How hard would it be to get boards made? I'm comfortable sourcing components, soldering, and sticking stuff in a case, but I'm clueless on where or how to get PCB's made. Wasn't there a sort of "automated" prototyping/small-quantity site where you could upload files and get back finished boards pretty reasonably? I'd love to try one of these, but I'm on a pretty strict budget these days.

Thanks for your hard work tse - I can't wait to see how this works with my own eyes.

SC
I'm working on a PCB layout and should have it finished soon. Will upload the files needed for getting boards. I use a Canadian company that charges about $47 for set-up then a couple of bucks per square inch. They only make the boards in pairs. Two of them will cost about $90.

www.apcircuits.com

If anyone knows of a place that is cheaper than this let me know.
post #21 of 492
Thread Starter 
Quote:
Originally Posted by WTS
Hi tse,
Good work,
So have you built some boards and tested this on a pj. Which pj did you test it on and how much of an improvement did you notice.
Not tested yet. I did build the green channel on the first design then discovered that my video sources do not have the back porch at zero volts. Doh! That's really the reason for the DCR version.

If your source does have the back porch clamped at zero volts the first version will work fine and be cheaper.

This circuit has been proven at my last job before VDC. The project there was developing a liquid crystal light valve projector that required an "S" shaped gamma correction with enhance at the dark video parts (like this project) as well as enhance in the brighter video levels.
post #22 of 492
Thread Starter 
Quote:
Originally Posted by Javers
Wow, this looks fab! tse any ideas on how much bandwidth these circuits can handle?

Jon
Though I have yet to test the bandwidth I expect 200MHz.
post #23 of 492
Thread Starter 
Quote:
Originally Posted by Clarence
Nice work tse.

Has anyone already created a bill of materials with component pricing and sources?
It's not yet finished. I've used common parts that can be had from many sources like Newark, Mouser, etc. Nothing exotic here. Should be fairly cheap to build.
post #24 of 492
Quote:
Originally Posted by tse
I'm working on a PCB layout and should have it finished soon. Will upload the files needed for getting boards. I use a Canadian company that charges about $47 for set-up then a couple of bucks per square inch. They only make the boards in pairs. Two of them will cost about $90.

If anyone knows of a place that is cheaper than this let me know.
What about $51 for 3 boards in the link posted above?

http://www.expresspcb.com/ExpressPCBHtm/Costs.htm
post #25 of 492
Quote:
Originally Posted by Clarence
What about $51 for 3 boards in the link posted above?

http://www.expresspcb.com/ExpressPCBHtm/Costs.htm
[ignorance]
Perhaps four layer is needed, as the big honkin groundplane would be handy for stifling interferance?
[/ignorance]
If so, the costs will be markedly higher...
http://www.expresspcb.com/ExpressPCB...erStandard.htm
$130 + ($0.87 * NumberOfBoards * BoardAreaInSquareInches) + ($1.25 * NumberOfBoards) + Shipping.
http://www.expresspcb.com/ExpressPCB...Production.htm
$260 + ($0.66 * NumberOfBoards * BoardAreaInSquareInches) + ($1.00 * NumberOfBoards) + Shipping.

If two layer will work, perhaps the ProtoPro service:
http://www.expresspcb.com/ExpressPCB...csProtoPro.htm
Production style, soldermask and silkscreen, for a fixed price of $179 for four boards.


I'll have a few of their "Production" boards in my hot little hands today for an office project. I'll report on the quality.
http://www.expresspcb.com/ExpressPCB...Production.htm
post #26 of 492
The boards I'm getting are from 4PCB.com and will be here tomorrow or friday, not expresspcb. Apparently, 4PCB was preferred by my EE management.
http://www.4pcb.com/pcb_milling_low_...tm#convenience

One interesting feature from these guys is a free gerber checker upload tool, FreeDFM
post #27 of 492
Quote:
Originally Posted by jtnfoley
The boards I'm getting are from 4PCB.com and will be here tomorrow or friday, not expresspcb.
Advanced Circuits (4PCB.com) is great as far as cost. I have run into a couple of problems with them at work but for personal stuff I use them all the time.

Good boards cheap and they run specials all the time.

Steve
post #28 of 492
http://img189.imageshack.us/img189/7546/tse01mux7qp.gif
Clamp R14 2.2K
Clamp R19 10K
Clamp R20 100
Clamp R21 50K variable
Clamp C16 100pF
Clamp C17 100nF
Clamp C18 100pF
Clamp U9A 74HC4538
Clamp U9B 74HC4538

In the “Misc†circuit, I renamed (in red) the duplicate C5 to C22:
http://img189.imageshack.us/img189/6...e02misc7ka.gif
Misc C5 22uF
Misc C22* 22uF
Misc C19 100nF
Misc D3 1N4002
Misc D4 1N4002
Misc F1 RXE040
Misc F2 RXE040
Misc J101 RawPwrIn 8v 15v
Misc J102 RegPwr 5v
Misc U3B/C/D 74HC86
Misc U4 MC7805
Misc U5 MC7905

http://img189.imageshack.us/img189/2...03clamp7pm.gif
Mux C13 100nF
Mux C14 100nF
Mux U8 74HC4053

In the “Video†circuit, I renamed (in red) the duplicate “R1†to “R7â€:
http://img189.imageshack.us/img189/8101/tse04vid4vh.gif
VID_R R1 2.4K
VID_R R7* 120
VID_R R2 430
VID_R R3 360
VID_R R4 75
VID_R R5 75
VID_R R6 75
VID_R R13 47K
VID_R C1 1000pF
VID_R C2 1000pF
VID_R C3 10uF
VID_R C4 10uF
VID_R C5 10uF
VID_R C6 1000pF
VID_R C7 1000pF
VID_R C8 10uF NP
VID_R D1 SD101A
VID_R D2 SD101A
VID_R U2 HFA1100
VID_G R1 2.4K
VID_G R7* 120
VID_G R2 430
VID_G R3 360
VID_G R4 75
VID_G R5 75
VID_G R6 75
VID_G R13 47K
VID_G C1 1000pF
VID_G C2 1000pF
VID_G C3 10uF
VID_G C4 10uF
VID_G C5 10uF
VID_G C6 1000pF
VID_G C7 1000pF
VID_G C8 10uF NP
VID_G D1 SD101A
VID_G D2 SD101A
VID_G U2 HFA1100
VID_B R1 2.4K
VID_B R7* 120
VID_B R2 430
VID_B R3 360
VID_B R4 75
VID_B R5 75
VID_B R6 75
VID_B R13 47K
VID_B C1 1000pF
VID_B C2 1000pF
VID_B C3 10uF
VID_B C4 10uF
VID_B C5 10uF
VID_B C6 1000pF
VID_B C7 1000pF
VID_B C8 10uF NP
VID_B D1 SD101A
VID_B D2 SD101A
VID_B U2 HFA1100

http://img189.imageshack.us/img189/1...e05sync4fg.gif
Sync C6 100nF
Sync C7 100nF
Sync C8 10nF
Sync C15 1nF
Sync D7 SD101A
Sync D8 SD101A
Sync J7 BNC
Sync J8 BNC
Sync R4 1K
Sync R6 1K
Sync R10 22K
Sync R11 22K
Sync R13 4.7K
Sync R16 10
Sync R18 47K
Sync R23 100
Sync U3A 74HC86
Sync U6 LM311

http://img189.imageshack.us/img189/5852/tse06sh3se.gif
SH_R C9 330nF
SH_R C10 10nF
SH_R C11 100nF
SH_R C12 100nF
SH_R R2 10K
SH_R R3 33K
SH_R R7 2.2K
SH_R R8 4.7K
SH_R R12 100
SH_R R15 160K
SH_R R17 10K
SH_R R22 10K
SH_R R33 2.7K
SH_R U7A/B TL082
SH_G C9 330nF
SH_G C10 10nF
SH_G C11 100nF
SH_G C12 100nF
SH_G R2 10K
SH_G R3 33K
SH_G R7 2.2K
SH_G R8 4.7K
SH_G R12 100
SH_G R15 160K
SH_G R17 10K
SH_G R22 10K
SH_G R33 2.7K
SH_G U7A/B TL082
SH_B C9 330nF
SH_B C10 10nF
SH_B C11 100nF
SH_B C12 100nF
SH_B R2 10K
SH_B R3 33K
SH_B R7 2.2K
SH_B R8 4.7K
SH_B R12 100
SH_B R15 160K
SH_B R17 10K
SH_B R22 10K
SH_B R33 2.7K
SH_B U7A/B TL082
post #29 of 492
http://img189.imageshack.us/img189/7546/tse01mux7qp.gif
Clamp R14 2.2K
Clamp R19 10K
Clamp R20 100
Clamp R21 50K variable
Clamp C16 100pF
Clamp C17 100nF
Clamp C18 100pF
Clamp U9A 74HC4538
Clamp U9B 74HC4538


In the “Misc†circuit, I renamed (in red) the duplicate C5 to C22:
http://img189.imageshack.us/img189/6...e02misc7ka.gif
Misc C5 22uF
Misc C22* 22uF
Misc C19 100nF
Misc D3 1N4002
Misc D4 1N4002
Misc F1 RXE040
Misc F2 RXE040
Misc J101 RawPwrIn 8v 15v
Misc J102 RegPwr 5v
Misc U3B/C/D 74HC86
Misc U4 MC7805
Misc U5 MC7905

http://img189.imageshack.us/img189/2...03clamp7pm.gif
Mux C13 100nF
Mux C14 100nF
Mux U8 74HC4053

In the “Video†circuit, I renamed (in red) the duplicate “R1†to “R7â€:
http://img189.imageshack.us/img189/8101/tse04vid4vh.gif
VID_R R1 2.4K
VID_R R7* 120
VID_R R2 430
VID_R R3 360
VID_R R4 75
VID_R R5 75
VID_R R6 75
VID_R R13 47K
VID_R C1 1000pF
VID_R C2 1000pF
VID_R C3 10uF
VID_R C4 10uF
VID_R C5 10uF
VID_R C6 1000pF
VID_R C7 1000pF
VID_R C8 10uF NP
VID_R D1 SD101A
VID_R D2 SD101A
VID_R U2 HFA1100
VID_G R1 2.4K
VID_G R7* 120
VID_G R2 430
VID_G R3 360
VID_G R4 75
VID_G R5 75
VID_G R6 75
VID_G R13 47K
VID_G C1 1000pF
VID_G C2 1000pF
VID_G C3 10uF
VID_G C4 10uF
VID_G C5 10uF
VID_G C6 1000pF
VID_G C7 1000pF
VID_G C8 10uF NP
VID_G D1 SD101A
VID_G D2 SD101A
VID_G U2 HFA1100
VID_B R1 2.4K
VID_B R7* 120
VID_B R2 430
VID_B R3 360
VID_B R4 75
VID_B R5 75
VID_B R6 75
VID_B R13 47K
VID_B C1 1000pF
VID_B C2 1000pF
VID_B C3 10uF
VID_B C4 10uF
VID_B C5 10uF
VID_B C6 1000pF
VID_B C7 1000pF
VID_B C8 10uF NP
VID_B D1 SD101A
VID_B D2 SD101A
VID_B U2 HFA1100

http://img189.imageshack.us/img189/1...e05sync4fg.gif
Sync C6 100nF
Sync C7 100nF
Sync C8 10nF
Sync C15 1nF
Sync D7 SD101A
Sync D8 SD101A
Sync J7 BNC
Sync J8 BNC
Sync R4 1K
Sync R6 1K
Sync R10 22K
Sync R11 22K
Sync R13 4.7K
Sync R16 10
Sync R18 47K
Sync R23 100
Sync U3A 74HC86
Sync U6 LM311

http://img189.imageshack.us/img189/5852/tse06sh3se.gif
SH_R C9 330nF
SH_R C10 10nF
SH_R C11 100nF
SH_R C12 100nF
SH_R R2 10K
SH_R R3 33K
SH_R R7 2.2K
SH_R R8 4.7K
SH_R R12 100
SH_R R15 160K
SH_R R17 10K
SH_R R22 10K
SH_R R33 2.7K
SH_R U7A/B TL082
SH_G C9 330nF
SH_G C10 10nF
SH_G C11 100nF
SH_G C12 100nF
SH_G R2 10K
SH_G R3 33K
SH_G R7 2.2K
SH_G R8 4.7K
SH_G R12 100
SH_G R15 160K
SH_G R17 10K
SH_G R22 10K
SH_G R33 2.7K
SH_G U7A/B TL082
SH_B C9 330nF
SH_B C10 10nF
SH_B C11 100nF
SH_B C12 100nF
SH_B R2 10K
SH_B R3 33K
SH_B R7 2.2K
SH_B R8 4.7K
SH_B R12 100
SH_B R15 160K
SH_B R17 10K
SH_B R22 10K
SH_B R33 2.7K
SH_B U7A/B TL082
post #30 of 492
http://img189.imageshack.us/img189/7546/tse01mux7qp.gif
Mux C13 100nF
Mux C14 100nF
Mux U8 74HC4053


In the “Misc†circuit, I renamed (in red) the duplicate C5 to C22:
http://img189.imageshack.us/img189/6...e02misc7ka.gif
Misc C5 22uF
Misc C22* 22uF
Misc C19 100nF
Misc D3 1N4002
Misc D4 1N4002
Misc F1 RXE040
Misc F2 RXE040
Misc J101 RawPwrIn 8v 15v
Misc J102 RegPwr 5v
Misc U3B/C/D 74HC86
Misc U4 MC7805
Misc U5 MC7905


http://img189.imageshack.us/img189/2...03clamp7pm.gif
Clamp R14 2.2K
Clamp R19 10K
Clamp R20 100
Clamp R21 50K variable
Clamp C16 100pF
Clamp C17 100nF
Clamp C18 100pF
Clamp U9A 74HC4538
Clamp U9B 74HC4538


In the “Video†circuit, I renamed (in red) the duplicate “R1†to “R7â€:
http://img189.imageshack.us/img189/8101/tse04vid4vh.gif
VID_R R1 2.4K
VID_R R7* 120
VID_R R2 430
VID_R R3 360
VID_R R4 75
VID_R R5 75
VID_R R6 75
VID_R R13 47K
VID_R C1 1000pF
VID_R C2 1000pF
VID_R C3 10uF
VID_R C4 10uF
VID_R C5 10uF
VID_R C6 1000pF
VID_R C7 1000pF
VID_R C8 10uF NP
VID_R D1 SD101A
VID_R D2 SD101A
VID_R U2 HFA1100
VID_G R1 2.4K
VID_G R7* 120
VID_G R2 430
VID_G R3 360
VID_G R4 75
VID_G R5 75
VID_G R6 75
VID_G R13 47K
VID_G C1 1000pF
VID_G C2 1000pF
VID_G C3 10uF
VID_G C4 10uF
VID_G C5 10uF
VID_G C6 1000pF
VID_G C7 1000pF
VID_G C8 10uF NP
VID_G D1 SD101A
VID_G D2 SD101A
VID_G U2 HFA1100
VID_B R1 2.4K
VID_B R7* 120
VID_B R2 430
VID_B R3 360
VID_B R4 75
VID_B R5 75
VID_B R6 75
VID_B R13 47K
VID_B C1 1000pF
VID_B C2 1000pF
VID_B C3 10uF
VID_B C4 10uF
VID_B C5 10uF
VID_B C6 1000pF
VID_B C7 1000pF
VID_B C8 10uF NP
VID_B D1 SD101A
VID_B D2 SD101A
VID_B U2 HFA1100


http://img189.imageshack.us/img189/1...e05sync4fg.gif
Sync C6 100nF
Sync C7 100nF
Sync C8 10nF
Sync C15 1nF
Sync D7 SD101A
Sync D8 SD101A
Sync J7 BNC
Sync J8 BNC
Sync R4 1K
Sync R6 1K
Sync R10 22K
Sync R11 22K
Sync R13 4.7K
Sync R16 10
Sync R18 47K
Sync R23 100
Sync U3A 74HC86
Sync U6 LM311


http://img189.imageshack.us/img189/5852/tse06sh3se.gif
SH_R C9 330nF
SH_R C10 10nF
SH_R C11 100nF
SH_R C12 100nF
SH_R R2 10K
SH_R R3 33K
SH_R R7 2.2K
SH_R R8 4.7K
SH_R R12 100
SH_R R15 160K
SH_R R17 10K
SH_R R22 10K
SH_R R33 2.7K
SH_R U7A/B TL082
SH_G C9 330nF
SH_G C10 10nF
SH_G C11 100nF
SH_G C12 100nF
SH_G R2 10K
SH_G R3 33K
SH_G R7 2.2K
SH_G R8 4.7K
SH_G R12 100
SH_G R15 160K
SH_G R17 10K
SH_G R22 10K
SH_G R33 2.7K
SH_G U7A/B TL082
SH_B C9 330nF
SH_B C10 10nF
SH_B C11 100nF
SH_B C12 100nF
SH_B R2 10K
SH_B R3 33K
SH_B R7 2.2K
SH_B R8 4.7K
SH_B R12 100
SH_B R15 160K
SH_B R17 10K
SH_B R22 10K
SH_B R33 2.7K
SH_B U7A/B TL082
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