this is de schemme i do from the RADICA board, if you can see we have 4 inputs to add to a OPERATIONAL AMPLIFYER with funtion INVERTER AMPLIFY. now i'm in testing this for inputs (A, B, C and D) to see what of those are RIGHT and LEFT stereo channel to amplify each one separately with another O.A.
the other images are 5v SMD 7805 regulator to carry cartridge enough current, and the LM358 DUAL O.A.
I don't understand how this can result into stereo since you just add all the channels with eachother by using that opamp... You'd have to split them again then?
the question is, a b c and d i dont know what are they, baut i'm testing. the solution is, locate RIGHT and LEFT (two of these A B C or D) and then use integrate O.A. in RADICA for example to RIGHT and put another Amplifier to LEFT then we must CUT the circuit because if we not CUT it in this case LEFT then ADD to RIGHT, we must separete them, the other two signals left are the question, but at this time important thig is know what of these 4 signals are left and right and then make another circuit with only one O.A. working as INVERTER AMPLIFYER. then we've got 2 outputs.
These 4 points ABCD are between CAPACITORS CE6, CE8, CE10 and CE11, They are typical TEST POINTS PADS. and this 4 capacitors are the first 4 capacitors in the scheme.
Last edited by Blackpata on Sat Jun 24, 2006 7:51 pm, edited 1 time in total.
i have not many time to test it (i'm all the day out of my home). this monday i can test it at work, with osciloscope and hearing the game, its possible right and left be there.
(sorry for my bad write english)
Last edited by Blackpata on Sat Jun 24, 2006 8:01 pm, edited 1 time in total.
oh it's a bit complicated explain you how to use, but in this case i suppose only hearing the game we can know what signas are. we can prove it desoldering 3 of this 4 capacitors and hear what happen, the same with each capacitor.
If anyone completes this mod and needs to test it for true stereo action (please do!) Columns is the easiest built-in to verify stereo. Just drop a block all the way on the sides to check, you should have only one drop sound coming from only the side the block is dropped on.
Finally, i found THE SOLUTION! now i finish my RADICA SLOT CARTRIDGE MOD and in this moment it's working with STEREO SOUND.
The mod it's easy, in the scheme, A and B are RIGHT channel, and C and D are LEFT.
Using the LM338 (dual O.A.) and cutting one via in the PCB (the union of RIGHT and LEFT). I used the 2 O.A. in the LM338 to amplify Right and Left respectively, each channel separately.
The radica finally have 3 RCA's, LEFT, RIGHT and VIDEO.