userDANC@mts.ucs.UAlberta.CA (unknown) (11/14/90)
Is anyone aware if a scheme exists to 'copy protect' commercial VHS tapes? In running a recent tape through a second video recorder, it looked as if the signal had become scrambled, though viewing it on a normal television worked fine. As a second year Electrical Engineering student, I would be very curious in learning the details of the protection scheme. (looks like I have a bit of catching up to do). Dan
otto@tukki.jyu.fi (Otto J. Makela) (11/23/90)
In article <1923@mts.ucs.UAlberta.CA> userDANC@mts.ucs.UAlberta.CA (unknown) writes:
Is anyone aware if a scheme exists to 'copy protect' commercial
VHS tapes? In running a recent tape through a second video recorder,
it looked as if the signal had become scrambled, though viewing it on
a normal television worked fine. As a second year Electrical Engineering
student, I would be very curious in learning the details of the protection
scheme. (looks like I have a bit of catching up to do).
Yes, there are copy protection schemes for VHS tapes (both NTSC and PAL).
And they are used.
Basically, what they do is mess up the recorded signal in a way that the 2nd
(recording) VCR won't like, but which won't affect TV viewing. The solution
is to take the composite or RGB signal that's coming out of the 1st VCR and
break it down to RGB + proper syncs and wipe everything else off the signal,
then combine everything up again.
One cheapo solution is to record in RF, but the quality stinks.
These were discussed in quite a lot of detail in Elektor (and they had plans
for a copy-protection remover), the issue number evades me at the moment.
--
/* * * Otto J. Makela <otto@jyu.fi> * * * * * * * * * * * * * * * * * * */
/* Phone: +358 41 613 847, BBS: +358 41 211 562 (CCITT, Bell 24/12/300) */
/* Mail: Kauppakatu 1 B 18, SF-40100 Jyvaskyla, Finland, EUROPE */
/* * * Computers Rule 01001111 01001011 * * * * * * * * * * * * * * * * */berggren@eecs.cs.pdx.edu (Eric Berggren) (11/24/90)
userDANC@mts.ucs.UAlberta.CA (unknown) writes: >Is anyone aware if a scheme exists to 'copy protect' commercial >VHS tapes? In running a recent tape through a second video recorder, >it looked as if the signal had become scrambled, though viewing it on >a normal television worked fine. As a second year Electrical Engineering >student, I would be very curious in learning the details of the protection >scheme. (looks like I have a bit of catching up to do). >Dan There are several companies using a "copy protection" scheme called... (damn! can't even remember the name). An easy way to tell if it is present is to set the V-Hold so that you can see the v-trace header at the top of the screen. If the tape has this scheme, you will see several flashing white boxes. Unfortunately, this "invisible" protection, wreaks havok on more sophisticated and sensitive VCR equipment images. However, Radio Electronics published an article couple years back called the "Macro Scrubber". This simple little box will remove this protection. (It is only for the purpose of improving the quality of the image and not for copying video cassettes. <right>! ) This is the only scheme that I know of. There are probably other, less popular ones. I haven't looked too deeply though. The box has seemed to do the job. ============================================================================== "Round and round the while() loop goes; Whether it stops," Turing says, "nobody knows."
dcschuur@sunee.waterloo.edu (DC Schuurman) (11/28/90)
In article <746@pdxgate.UUCP> berggren@eecs.cs.pdx.edu (Eric Berggren) writes: >userDANC@mts.ucs.UAlberta.CA (unknown) writes: > >>Is anyone aware if a scheme exists to 'copy protect' commercial >>VHS tapes? In running a recent tape through a second video recorder, >>it looked as if the signal had become scrambled, though viewing it on >>a normal television worked fine. As a second year Electrical Engineering >>student, I would be very curious in learning the details of the protection >>scheme. (looks like I have a bit of catching up to do). >>Dan > > There are several companies using a "copy protection" scheme called... MACROVISION ENCODING ! I replied personally to the original sender assuming someone else would identify the copy scheme but I'll post it here for anyone else who cares... The scheme is simple yet effective - several large high frequency spikes are inserted prior to and during the vertical blanking interval - Normally a television will ignore these high frequency pulses due to the low pass characteristic of the deflection circuitry during the retrace - BUT a VCR will adjust it's Automatic Gain Control (AGC) to these large incoming spikes and because of the finite time constant involved with the AGC response the following picture field will appear dark and murky if copied from another MacroVision protected tape. These large spikes are visible (as the genetleman above mentioned) as flashing squares in the black line on your TV which appears during vertical retrace. The scheme is effective yet simple - however there have been some problems with very expensive multi-synch TV's which interpret these high frequency noise bursts as a higher horizontal synch frequency and vainly try to adjust to these noise pulses mistaking them as a change in H synch. The cheapest TV's seem to be least susceptible to MacroVision interference while viewing Macrovision encoded tapes - strange but true. So there it is - I hope this helps Derek C. Schuurman University of Waterloo Electrical Engineering Hoping to Graduate in '91 - Got a job for me?
wilker@gauss.math.purdue.edu (Clarence Wilkerson) (11/28/90)
If you look in ads in Radio-Electronics, there are several to clean up Macrovision pictures. I built one for $30 from a kit that seemed to work. Clarence
berggren@eecs.cs.pdx.edu (Eric Berggren) (11/28/90)
dcschuur@sunee.waterloo.edu (DC Schuurman) writes: >> There are several companies using a "copy protection" scheme called... >MACROVISION ENCODING ! >BUT a VCR will adjust it's Automatic Gain Control (AGC) to these large >incoming spikes and because of the finite time constant involved with the >AGC response the following picture field will appear dark and murky >if copied from another MacroVision protected tape. These large spikes >are visible (as the genetleman above mentioned) as flashing squares >in the black line on your TV which appears during vertical retrace. >The scheme is effective yet simple - however there have been some problems >with very expensive multi-synch TV's which interpret these high frequency >noise bursts as a higher horizontal synch frequency and vainly try to >adjust to these noise pulses mistaking them as a change in H synch. >The cheapest TV's seem to be least susceptible to MacroVision >interference while viewing Macrovision encoded tapes - strange but true. Makes sense why R-E called it a "Macroscrubber"... I heard that this protection system wreaks havok with the HDTV in the labs. I doubt "they" are going to make changes just to deal with VHS copy protection schemes. I'm sure the industry will eventually develop ssomething else, probably just to elude all of the "macroscrubbers" and make our lives, and pictures, more enjoyable. Might as well let the Japanese buy Paramount too; I doubt they care about the whole issue of protection... ============================================================================== "Round and round the while() loop goes; Whether it stops," Turing says, "nobody knows." ============================================================================== "Round and round the while() loop goes; Whether it stops," Turing says, "nobody knows."
rjb@cbnewsj.att.com (richard.j.bavier) (11/28/90)
> > Makes sense why R-E called it a "Macroscrubber"... > Does anyone know what issue of R-E describes the "Macroscrubber"?
markz@ssc.UUCP (Mark Zenier) (12/01/90)
In article <1990Nov28.131153.18564@cbnewsj.att.com>, rjb@cbnewsj.att.com (richard.j.bavier) writes: > > Makes sense why R-E called it a "Macroscrubber"... > Does anyone know what issue of R-E describes the "Macroscrubber"? December 1987 markz@ssc.uucp
wilker@gauss.math.purdue.edu (Clarence Wilkerson) (12/02/90)
I don't have the issue number for the R-E Macro Scrubber, but D&D Electronics in Jan. 1991 (latest) advertises the kit (no fancy box) for $29 + $4 S/H phone is 1-800-332-3557 or 1-508-699-6935 Clarence Wilkerson Usual Disclaimers........
crc@raider.raidernet.com (Charles Cain) (12/04/90)
userDANC@mts.ucs.UAlberta.CA (unknown) writes: >Is anyone aware if a scheme exists to 'copy protect' commercial >VHS tapes? In running a recent tape through a second video recorder, >it looked as if the signal had become scrambled, though viewing it on >a normal television worked fine. As a second year Electrical Engineering >student, I would be very curious in learning the details of the protection >scheme. (looks like I have a bit of catching up to do). >Dan Yes Dan there is a copy protection scheme on VHS tapes. The name is called Macrovision, and the principle is somewhat simple. On I believe Line 14 of Field 1, you will notice some flashing white lines. This is the copy protection scheme. The method works on the demodulation/remodulation mode. The TV set is happy because it does not remodulate the baseband video. However, when you try to copy the tape, the 2nd VCR has to remodulate the baseband video into FM. I am guessing after this. The copy scheme senses this and increments or decrements a count, which then enables the protection portion of the code. Then, when the copied tape is demodulated into baseband, the setup portion of the video constantly moves up and down, giving the VCR fits and the TV. On a purely thereoretical basis, I would suppose that someone could defeat the scheme by (a) recording in FM only, or (b) running the original tape through a processing amplifier, which will strip out the vertical interval and replace it with it's own. I would think this would work, I don't know for a fact. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- DOMAIN: crc@raider.raidernet.com | From NASHVILLE, TENNESSEE Engineer, The Nashville Network | JESUS IS MY LORD!!!!! ----------------------------------------------------------------------------- Disclaimer: These words do not reflect or express the views of The Nashville Network in any way. The words and the way they are used is solely MY FAULT!!! -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
ron@vicorp.com (Ron Peterson) (12/04/90)
In article <1990Nov28.131153.18564@cbnewsj.att.com> rjb@cbnewsj.att.com (richard.j.bavier) writes: >> >> Makes sense why R-E called it a "Macroscrubber"... >> > >Does anyone know what issue of R-E describes the "Macroscrubber"? Also, does anyone know what issue has the fixes to the circuit to make it work better?
paulm@ccicpg.UUCP (Paul Moreau) (12/07/90)
In artical <796@pdxgate.UUCP>, berggren@eecs.cs.pdx.edu writes: > > rjb@cbnewsj.att.com (richard.j.bavier) writes: > > >> > >> Makes sense why R-E called it a "Macroscrubber"... > >> > > >Does anyone know what issue of R-E describes the "Macroscrubber"? > > I'm not sure what issue it is. It's 2-3 years old though. If your local > library caries a subscription, check their back issues. I haven't got > around to looking for and build it yet. There seems to be enough intrest out there that I thought this artical I grabbed off here about a year ago warented re-posting: ---- Well here it is. Since I've had so many request for this goody I thought I'd just post it instead. This Macrovision Eliminator is about as good as I can get it. It has a bandwidth well over 10mhz and should be able to drive a number of devices in parallel. For those who plan to make one I must warn you that I take no responsibilty for anything (my disclaimer :-)). I have tried it on a number of different tapes, VCRs and TVs so it should work good for everybody. Have fun!!! Yeah, I can finally rent tapes again! Notes: This also eliminates time codes and close caption information. Sorry about the cryptic schematic but what can you do when all you have is ASCII to work with. If you don't see a + at an intersection it isn't connected. ____________ | LM1201 | Video 10uf 16| |12 In >-----+--+--||---+--------------------|In Vcc2|--------------+--<+12v | | + | 1N914 3| |15 200 | | | +--|<|--+------------|Vref Vcc1|------/\/\/---+ Video | | | .1uf | |10 75 | In >------------>Gnd +--||--+ | Vcc3|------/\/\/---+ | | 75 | | | | +--------------/\/\/---+ | | | 10k | | |13 .1uf +12v>--------+---/\/\/--------------+ | Cont.C.|------||------+ | | |Gain | 4| | | | | +----------------------|Contrast | | | | 10k | | |14 | | +---/\/\/--------------+ | Cont.C.|--------------+ | | |Offset | 6| | | | +----------------------|Clamp+ | | | 5.1k 43k | | | | +---/\/\/---+--/\/\/---+ | | | 1000pf | | 5| |11 51 | +----||-----+----------------|C.G. Drive|------/\/\/---+ | | | 8| |2 .1uf | +-----------------+----------------|Out Ccap|-------||-----+ | | | | 75 | | |7 | | | | +--/\/\/---+ | Gnd2|--------------+ | | | | 200 | 9| |1 | | | | +--/\/\/---------|Clamp- Gnd1|--------------+ | | | | |____________| | | | | | A1 | Gnd>--------------------------------+---------------------------------+ | | | | | | | | +------------------------------------+ | | ____________ | | | | LM1881 | | | | 8| |1 | | | +12v>---|Vcc Csync|----------+ | | .1uf 2| |5 | | | +-----------||------|In Burst|------+ | | 680 6| |3 | | +--/\/\/-+--------|Rset Vsync|------+ | | | .1uf | 4| |7 | | | +---||---+ +---|Gnd Field|- | | | | | |____________| | | | | | A2 | | | | | 450 750 | | Gnd>--------+-------------+--/\/\/---+---/\/\/----+ | | | | | +-------------+ | | | | | +-----------------------------------------+ | | | | | | ____________ | | | | 74LS221 | | | | 1| (1/2) |16 | | +------|A1 Vcc|----<+5v | | 2| |13 | | +5v>---+---|B1 Q1|------+ | | | 3| | | | | +---|Rst1 | | | | .1uf 14| __|4 | | |Position+--||----|C1 Q1|- | | | 10k | 15| | | +5v>----------/\/\/--+--------|R/C1 | | | | | | |____________| | | | +----+ A3 | | | +--------------------------+ | | | | | | ____________ | | | | 74LS221 | | | | 9| (1/2) |8 | | +------|A2 Gnd|---<Gnd | | 10| |5 | | +5v>---+---|B2 Q2|------------+ | | | 11| | | | | +---|Rst2 | | | | .1uf 6| __|12 | | | Width +--||---|C2 Q2|- | | | 10k | 7| | | +5v>-----------/\/\/--+-------|R/C2 | | | | | | |____________| | | | +----+ A3 | | | 750 450 | | +--/\/\/-----+----/\/\/---<Gnd | | | | | +----------------------------------+ | | | | | | | ____________ | | | | | 74LS221 | | | | | 1| (1/2) |16 | | | +----|A1 Vcc|----<+5v | | | 2| |13 | +5v>-------+------------------|B1 Q1|- | | | | 3| | | | | +--------|Rst1 | | | | .01uf 14| __|4 | | |EQ.Start +--||----|C1 Q1|------+ | | | 20k | 15| | | | | +--/\/\/--+--------|R/C1 | | | | | | |____________| | | | +----+ A4 | | | +--------------------------+ | | | | | | ____________ | | | | 74LS221 | | | | 9| (1/2) |8 | | +------|A2 Gnd|---<Gnd | | 10| |5 | | +5v>---+---|B2 Q2|- | | | 11| | | | +---|Rst2 | | | 1000pf 6| __|12 | | EQ.Width +--||---|C2 Q2|------+ | | 20k | 7| | | | | +5v>--/\/\/--+-------|R/C2 | | | | | | |____________| | | | +----+ A4 | | | | | | +------------------------------------+ | | | | | +-------------------------+ | | | | | | ____________ | | | | 74LS00 | | | | 1| |14 | | +-----|In1 Vcc|-----<+5v | | 2| |3 | +----------|In2 Out1|------+ | 7| | | | Gnd>-------|Gnd | | | |____________| | | A5 | | +------------------------------+ | | ____________ | | | LF1333 | | | 4| |5 | Gnd>---------------|Gnd V-|-----<-12V | | 16| |12 | +----------|In1 V+|-----<+12v | | 14| |15 10uf 75 | +---------------|S1 D1|-----+--||---/\/\/----->Video Out | | | 1| | | + | | +----------|In2 | | Gnd>--------->Video Out | | 3| |2 | +----------------------|S2 D2|-----+ | |____________| | A6 | +12v>----/\/\/--<Gnd 5k Blanking SOME NOTES: You can replace some of the pots with fixed resistors if you like. The OFFSET pot can be replaced with a 7.85k to +12v and a 1.43k resistor to ground. The POSITION pot can be replaced with a 6.25k resistor. The WIDTH pot can be replaced with a 6.81k resistor. The BLANKING pot can be replaced with a 4.18k resistor to +12v and a 592ohm resistor to ground. I do not recommend replacing any of the other pots with fixed values. If you do use fixed resistors please skip those steps in the adjustment procedure. TIMING DIAGRAM AND ADJUSTMENT PROCEDURE: Set up: Connect a scope up to the video input and trigger on vertical sync. Make sure you can still see past the Macrovision pulses. The second channel will be used for looking at the device being adjusted. Pre-adjust all pots for center position. 1. Connect the 2nd channel on the scope up to A1-pin8. 2. Adjust GAIN for 1 volt peak to peak output. 3. Adjust OFFSET for a 1-2 volt DC offset. 4. Connect the 2nd channel on the scope up to A3-pin13. 5. Adjust POSITION so the falling edge of the signal is in the middle of the horiz. line just before the Macrovision pulses (see timing). 6. Connect the 2nd channel of the scope up to A3-pin5. 7. Adjust WIDTH so the falling edge of the signal is in the middle of the horiz. line just after the Macrovision pulses (see timing). Macrovision |<------------------->| ||||| ||||| ||||| ||||| _______ ____________|||||_|||||_|||||_|||||________ Video In | |_____|_____|_____| | ||||||||||||||||||||||||| | _______ ___________________________________________ Vsync (A2-pin3) |_________________| __________________________ Q1 (A3-pin13) ___| |__________________________________ ______________________________ Q2 (A3-pin5) ______________________________| |___ __ _________________________________________________________________ Q1 (A4-pin12) | | | | | ______________________________ ___ Out (A5-pin3) |__|_____|_____|_____|_____|___| ________ ___________________________________________ Video Out | |_____|_____|_____| | | | | | | | 8. Connect the 2nd channel of the scope up to A4-pin4. 9. Adjust EQ.START so the rising edge of the signal is just after the single Macrovision Burst (see timing) 10. Connect the 2nd channel of the scope up to A4-pin12. 11. Adjust EQ.WIDTH so the signal is low during the equalization pulses and goes high just after the color burst signal (see timing). 12. Connect the 2nd channel of the scope up to Video Out. 13. Adjust BLANKING level to match the rest of the videos blanking. 14. The video output should now look like Macrovision never existed. 15. Try it! A Single Macrovision Burst |<--------------------------------->| _ _ _ _ _ _ _ | | | | | | | | | | | | | | _________ _ | |_ | |_ | |_ | |_ | |_______ _ | |_ | |_ Video In |_| |_| |_| |_| |_| |_| |_| |_| |_| | _______________________________________________________________ Q2 (A3-pin5)___| __________ _ ___ ___ ___ ___ _________ _ ___ ___ Csync (A2-pin1) |_| |_| |_| |_| |_| |_| |_| |_| |_| | __ __________ ____ Q1 (A4-pin4) |__________________________________| |________________ __ __________ ___________________________________ ____________ Q2 (A4-pin12) |___| |___| If there is anything I forgot to mention or is unclear (I know, too late) send me mail and I'll try to clear it up. Mark Quattrocchi From: mark@cygnet.CYGNETSYSTEMS (Mark Quattrocchi) Subject: Macrovision Eliminator Date: 11 Jul 88 00:05:21 GMT I hope I didn't miss too many questions about my macrovsion eliminator while our news feed was down. If so please repost or send me mail. I did receive a couple of questions and thought I'd post instead of mail. Some people are having problems getting the National Semi LM1201, and I thought I'd explain. The LM1201 is new and will be in production shortly (well thats what they tell me :-)). I got mine from the first sample run. Since some of you are trying to build this goody I figured I'd send you another version that does not use that part. Also I modified the schematic so you can use a single supply voltage (though you smart folks would have figured that out anyway). A voltage between 16-35vdc will run this, however if you use a supply over 24vdc you will probably need to add a heat sink for the voltage regulators. I'd like to thank Bill McFadden for the DC restorer circuit which I show as the LM1201 replacement (hope it works Bill :-)) and left his article in tact by only appending the rest of the macrovision circuit to his DC restorer. For those who plan to make one I must warn you that I take no responsibilty for anything (my disclaimer :-)). I can't speak for Bill but you can ask him yourself. I hope he doesn't mind me doing this!?!? Notes: This also eliminates time codes and close caption information. Sorry about the cryptic schematic but what can you do when all you have is ASCII to work with. If you don't see a + at an intersection it isn't connected. All voltages used on A1-A6 are supplied by the two voltage regulators shown at the bottom of this schematic. Just a note: The op amp used below must be a video op amp like the RCA CA3100. C | | VIDEO IN O------+------| |------+----------------+---------------+ | | | | | | | | |\ ___ | | | | \ / \ (DIODE) | +----/\/\/\-----+----|- \ | | R | >----+ | +----|+ / | | | / | | |/ | ___ | /// | | +------------------------------------------------------------+ Video | In >-----+ | | Video | | In >------------>Gnd | | | | | | | | ____________ | | | LM1881 | | | 8| |1 | | +12v>---|Vcc Csync|----------+ | | .1uf 2| |5 | | +-----------||------|In Burst|-- | | 680 6| |3 | | +--/\/\/-+--------|Rset Vsync|------+ | | | .1uf | 4| |7 | | | +---||---+ +---|Gnd Field|- | | | | | |____________| | | | | | A2 | | | | | 450 750 | | Gnd>--------+-------------+--/\/\/---+---/\/\/----+ | | | | | +-------------+ | | | | | +-----------------------------------------+ | | | | | | ____________ | | | | 74LS221 | | | | 1| (1/2) |16 | | +------|A1 Vcc|----<+5v | | 2| |13 | | +5v>---+---|B1 Q1|------+ | | | 3| | | | | +---|Rst1 | | | | .1uf 14| __|4 | | |Position+--||----|C1 Q1|- | | | 10k | 15| | | +5v>----------/\/\/--+--------|R/C1 | | | | | | |____________| | | | +----+ A3 | | | +--------------------------+ | | | | | | ____________ | | | | 74LS221 | | | | 9| (1/2) |8 | | +------|A2 Gnd|---<Gnd | | 10| |5 | | +5v>---+---|B2 Q2|------------+ | | | 11| | | | | +---|Rst2 | | | | .1uf 6| __|12 | | | Width +--||---|C2 Q2|- | | | 10k | 7| | | +5v>-----------/\/\/--+-------|R/C2 | | | | | | |____________| | | | +----+ A3 | | | 750 450 | | +--/\/\/-----+----/\/\/---<Gnd | | | | | +----------------------------------+ | | | | | | | ____________ | | | | | 74LS221 | | | | | 1| (1/2) |16 | | | +----|A1 Vcc|----<+5v | | | 2| |13 | +5v>-------+------------------|B1 Q1|- | | | | 3| | | | | +--------|Rst1 | | | | .01uf 14| __|4 | | |EQ.Start +--||----|C1 Q1|------+ | | | 20k | 15| | | | | +--/\/\/--+--------|R/C1 | | | | | | |____________| | | | +----+ A4 | | | +--------------------------+ | | | | | | ____________ | | | | 74LS221 | | | | 9| (1/2) |8 | | +------|A2 Gnd|---<Gnd | | 10| |5 | | +5v>---+---|B2 Q2|- | | | 11| | | | +---|Rst2 | | | 1000pf 6| __|12 | | EQ.Width +--||---|C2 Q2|------+ | | 20k | 7| | | | | +5v>--/\/\/--+-------|R/C2 | | | | | | |____________| | | | +----+ A4 | | | | | | +------------------------------------+ | | | | | +-------------------------+ | | | | | | ____________ | | | | 74LS00 | | | | 1| |14 | | +-----|In1 Vcc|-----<+5v | | 2| |3 | +----------|In2 Out1|------+ | 7| | | | Gnd>-------|Gnd | | | |____________| | | A5 | | +------------------------------+ | | ____________ | | | LF1333 | | | 4| |5 | Gnd>---------------|Gnd V-|-----<Gnd | | 16| |12 | +----------|In1 V+|-----<+12v | | 14| |15 10uf 75 | +---------------|S1 D1|-----+--||---/\/\/----->Video Out | | | 1| | | + | | +----------|In2 | | Gnd>--------->Video Out | | 3| |2 | +----------------------|S2 D2|-----+ | |____________| | A6 | +12v>----/\/\/--<Gnd 5k Blanking __________ | 7812 | | +12v | 16-35VDC>---------+------------|In Out|-----+-------+------>+12v | | | |+ | GND>----------------+-----|Gnd | === === | | |__________| |10uf |.01uf | | | | | +----------------------+-------+------>Gnd | | __________ |10uf |.01uf | | | 7805 | === === | | | +5v | |+ | +------------|In Out|-----+-------+------>+5v | | | +-----|Gnd | |__________| SOME NOTES: You can replace some of the pots with fixed resistors if you like. The OFFSET pot can be replaced with a 7.85k to +12v and a 1.43k resistor to ground. The POSITION pot can be replaced with a 6.25k resistor. The WIDTH pot can be replaced with a 6.81k resistor. The BLANKING pot can be replaced with a 4.18k resistor to +12v and a 592ohm resistor to ground. I do not recommend replacing any of the other pots with fixed values. If you do use fixed resistors please skip those steps in the adjustment procedure. TIMING DIAGRAM AND ADJUSTMENT PROCEDURE: Set up: Connect a scope up to the video input and trigger on vertical sync. The second channel will be used for looking at the device being adjusted. Pre-adjust all pots for center position. 1. Connect the 2nd channel on the scope up to A3-pin13. 2. Adjust POSITION so the falling edge of the signal is in the middle of the horiz. line just before the Macrovision pulses (see timing). 3. Connect the 2nd channel of the scope up to A3-pin5. 4. Adjust WIDTH so the falling edge of the signal is in the middle of the horiz. line just after the Macrovision pulses (see timing). Macrovision |<------------------->| ||||| ||||| ||||| ||||| _______ ____________|||||_|||||_|||||_|||||________ Video In | |_____|_____|_____| | ||||||||||||||||||||||||| | _______ ___________________________________________ Vsync (A2-pin3) |_________________| __________________________ Q1 (A3-pin13) ___| |__________________________________ ______________________________ Q2 (A3-pin5) ______________________________| |___ __ _________________________________________________________________ Q1 (A4-pin12) | | | | | ______________________________ ___ Out (A5-pin3) |__|_____|_____|_____|_____|___| ________ ___________________________________________ Video Out | |_____|_____|_____| | | | | | | | 5. Connect the 2nd channel of the scope up to A4-pin4. 6. Adjust EQ.START so the rising edge of the signal is just after the single Macrovision Burst (see timing) 7. Connect the 2nd channel of the scope up to A4-pin12. 8. Adjust EQ.WIDTH so the signal is low during the equalization pulses and goes high just after the color burst signal (see timing). 9. Connect the 2nd channel of the scope up to Video Out. 10. Adjust BLANKING level to match the rest of the videos blanking. 11. The video output should now look like Macrovision never existed. 12. Try it! A Single Macrovision Burst |<--------------------------------->| _ _ _ _ _ _ _ | | | | | | | | | | | | | | _________ _ | |_ | |_ | |_ | |_ | |_______ _ | |_ | |_ Video In |_| |_| |_| |_| |_| |_| |_| |_| |_| | _______________________________________________________________ Q2 (A3-pin5)___| __________ _ ___ ___ ___ ___ _________ _ ___ ___ Csync (A2-pin1) |_| |_| |_| |_| |_| |_| |_| |_| |_| | __ __________ ____ Q1 (A4-pin4) |__________________________________| |________________ __ __________ ___________________________________ ____________ Q2 (A4-pin12) |___| |___| If there is anything I forgot to mention or is unclear (I know, too late) send me mail and I'll try to clear it up. Mark Quattrocchi ---- .==========================================================. | UUCP: ..uunet!ccicpg!dl2!paulm | Paul L. Moreau | | or ..uunet!ccicpg!dl1!paulm | Sr. Diag Software Eng. | | or ..uunet!ccicpg!paulm | Irvine, California | `=========================================================='