Quote Originally Posted by marc133 View Post
Hi just wondering if there had to be a mod made on a STRONG SATELLITE Receiver - 4658X used with a gamma?
I've read that there had to be a mod with the Humax 5400Z Card reader to drop the voltage, to prevent overheating.
Just wondering if something simmilar had to be done to the Strong box.
Much Appreciated
Yes there is a mod ...

... and no you don't need a resistor or diode or even a volt regulator to drop the 5V supply to the card to 3V ...

... many mods discussed here do the unthinkable ... as was already covered in another post by gw1 ... dropping voltage to the card alone without proper care of the interface electronics can 'break' your smartcard


Quote Originally Posted by mickc View Post
no mod needed on newer strongs
... not exactly true ...

If we assume that gamma cards run of +3V - then even though they may indeed operate at +5V and be able to dissipate the 'heat' ... they are not running within their ideal specification that of +3V ...

The card reader on the STRONG 4658X as well as many other receivers use a TDA8024 IC card interface ...



... the clever thing about this device is that it already has a +3V mode of operation ... by examining the data sheet (above link) we can see that pin 3 - when strapped to +5v will operate the card interface at 5V - if we GND pin 3 then the card interface will operate at +3V ...

If we examine the card reader PCB on the 4658X - then we will see that pin 3 is at +5V - as expected ... to change the mode of operation of the card reader to +3V - we need to tie pin 3 to GND ...

WARNING : No we don't just 'tie' pin 3 to GND ... we need to unsolder the pin - 'lift' it so it does not touch any other tracks ... and finaly 'tie' the naked pin 3 to GND ...

See picture of completed mod ...

If you do indeed make this mod - PLEASE check the voltage of the card reader - by inserting the 'rear' of your gamma - so that no contact is made to its landing pads ... just in case you 'botched' the mod ... you don't want to fry your gamma ...

... by inserting the card ... we trigger the micro contact of the reader socket and enable the 'voltage' to turn-on ... we can then measure between pins C1 and C5 which are clearly marked on the PCB ...

GOOD LUCK ... and lets stop all of the 'he' said , 'she' said modify this resistor / add this diode type of mods ... the above IS in effect a FACTORY mod for +3V operation on all card readers utilizing a TDA8024 IC card interface ... so it can be applied to any receiver which uses this chip