did you buy it from mikedata ?? if so, there will be a guide on the disc he provides and the pots are useualy set up for certain rom.
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Guide For Use:
The 1st thing you will do is to open winexplorer and make sure you are on the right comport and you have set it to my looper in program parameters. Also no need to flash the dual has I have done this for you, but if you do want to
Flash the dual always make sure you have dip 2 on and the rest off; dip 2 should always be on at all times i.e. flashing/unlocking cards?
2. Now you need to know what card you are trying to open...i.e. Rom10 or Rom11 and then the card revision....i.e. Rom10 A86 or Rom11 B0D (The most common revisions there are many more)
3. Let's say it's a Rom11 (Rev) BOD, you will need to make sure that the Dual is on bank B (For Rom11 Cards) , you will now need to load up the BOD unlocker script with winexplorer, Now put you card in the unlooper (Chip facing forwards and down) and hit the Run Script tag in winexplorer and sit back....
4. Vcc-....If your Vcc is to high or to low, You will need to adjust this by turning the brass screw on top of the little blue pot until you get around 26 to 27 (Remember this is the optimum Vcc For a Rom11) , but as you are doing this the card may open anyway....
5. When the card has opened you will here a beep from your pc and a display in winexplorer saying that bugs have been zeroed.
6. Now take the card out of the Dual and put it in your programmer, setting your programmer into phoenix mode along the way, The best ones to use are the DYNAMITE or the Infinity USB phoenix as they have a USB and comport giving better compatibility, where as the Infinity USB Unlimited only has a USB port and therefore does the phoenix over VCP (Virtual Comport) this is where allot of people have problems as they cant seem to get this set up right and get loads of problems whilst trying to read the newly unlocked Rom Card, these errors can include : NO ATR and Setifs errors amongst others.
7. Now we use Nagraedit 4.1 to read the card..... (Later versions of Nagraedit will give errors upon trying to read a Rom10 or Rom11 card so make sure you only use version 4.1, similar can be said of earlier versions also)
Once in Nagraedit and after making sure the com port is set to the correct one, click the Blue Arrow to commence reading of the card.
8. This is all the help I will give on this, because at the end of the day I have not the time to baby sit peeps who don't take the time to read up on there hardware or software setup and usage....there is plenty of information on the forums regarding possible errors including the unlooping side of things and possible problems reading the card in nagra.
9. If you have a tiny unlooper it the same as the dual but only as hc4053 or hct4053 and not both like the dual unlooper??
10. with the tiny and the dual you should use the tiny2313 flash and NOT xpatmel, you should load both the EPROM exe & the program exe into the tiny software, if you don?t do this some scripts will give a error of 4 bytes and will not tell what flash you have flashed you unlooper
11.vcc setup, moving from bank A to bank B, when you go back to bank B you will need to turn your Vcc down by going ant clock wise till it comes down to a Vcc of 27 and if you don?t do this your Vcc will be about 40+?..once you have set the Vcc to around 28 to 24 and as long as you are around that mark you will open most rom11 and you will NOT have to re-adjust the Vcc again..
12 going back to bank a, the best way I find for most peeps and it is so easy, just turn the pot clockwise until you hear a little click coming from the pot, once you hear this you will need to do 4 to 6 FULL turn's to the pot ant clock wise, this will give you a Vcc of about 40+ but you will not get this on some cards it maybe more or it could be lower, now put you rom10 and run the script and as you look at the screen you should see --++++++++++--Hit40+++++-Hit40 This is your Vcc ?Hit40? or you need to do now is to get the Vcc down to 1A to 1B.........and that is it you dual should now be setup right now for rom10 and on bank A
13. Finally there you have it, if you can?t do any of the above take a look on the various forums and does a lot of reading or better still start something new like fishing... 
Regards
MIKEDATA
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