anyone have the 233 emu diagram

[day_tona2]

anyone know where i can get a diagram to make an internel emu with the 233 and 2313 chip.....

the 233 chip is a 20 pin

[craneguy]

yea i will upload one.

[ruciz]

comment: Requires no external caps.
comment: Make no connections to pins 8 and 13.
comment: Pins 12 and 17 must be tied together.
comment: Pins 11 and 15 must be tied together.
comment: pins 10 and 16 must be tied together.

+--()--+
T2in | 1 20| R2out
T1in | 2 19| R2in
R1out | 3 18| T2out
R1in | 4 17| V-
T1out | 5 16| C2-
GND | 6 15| C2+
VCC | 7 14| V+
C1+ | 8 13| C1-
GND | 9 12| V-
C2- |10 11| C2+
+------+

MAX232A

+---v---+
C1+ -|1 16|- Vcc
V+ -| |- GND
C1- -| |- T1out
C2+ -| |- R1in
C2- -| |- R1out
V- -| |- T1in
T2out -| |- T2in
R2in -|8 9|- R2out
+-------+

should be all you need to know. make all pins on the 232 diagram go to the corresponding 233 pin locations.

[day_tona2]

ok do i need the 10uf between the ground and power?

[BGW]

Mine works fine without it.

[ruciz]

10uF I recommend, it just smooths any EMI/RF off the power and ground lines.. the board itself makes a lot of this noise especially at the 141MHz range (emergency distress signal)

You can make due with any cap from 100uF to 1uF.. its only a filter cap so value isn't important. I would make sure its a 25V tho and not like a 200V or something.

[day_tona2]

what about a 50 v

[ruciz]

It should be suitable. Try it and see what happens...

Long as your voltage is rated above what the schematic calls for you should be fine, same with the farad rating. going below could be a problem.. so scratch the idea of the 1uF.. get at least a 10uF at 25V.

[day_tona2]

i pulled it off a 301 i fryed its a 10 uf 50v