SimCom© Mark I

Intercom for computer simulators

SimCom© is an intercom for computer (flight)simulators, suitable for all multiplayer games/simulators. It has a built in noise generator to simulate radio interference and it mixes your computers sound with your outgoing voice to simulate background sounds from your cockpit. It runs on battery (9V) or AC adapter (5-12VAC or /7-16VDC). You can connect several (we don't now exactly how many, but 6 works fine) SimComs© on one or two twisted pair cables. It is made to enhance the realism of your simulation, so it's defiantly no Hi-Fi quality sound. You can adjust the level of noise and interference from none to a level where it's almost impossible to hear anybody.

SimCom© works in simplex mode, this means that while you press your PTT (push to talk) button you don't hear anything from any of the other players, and while you don't press it you hear all the other players that do press there PTT. It has two channels, one is typically for communicating with your wingman or RIO and the other are for the whole group. The PTT is a three position switch, spring loaded to the center position. In center position you receive all thats going on on both channels and the other positions are for sending on channel one or two.

SimCom© is shareware (probably the only hardware shareware ?) and you may distribute these files as the contents are not changed or altered in any way. If you decide to build it, all we ask is that you send us a postcard.

If you send us US$10 we will E-mail you the PCB layout in HPGL and BMP format and the component placing in BMP format. If you prefer to, you can also buy it from us in different forms. If you send $20 we will mail you the PCB, the circuit board without components and without holes, add $10 if you want us to drill it for you. You can also buy the complete thing as a kit including headset or built and tested including headset, in both cases we do not include any box, casing or power supply, you will have to build it into a panel or something yourself. Contact us for prices.

We are not, and can not be held responsible for any damage or injury to any thing or person that might occur due to the use of or when building the SimCom©. If you are not familiar with building this type of electronics, find someone that can do it for you. We can not guarantee the function for SimComs not build and tested by us.

There is a ZIP-file ( that includes the following...

On Internet contact:
Christer Johansson
Åsbogatan 29c
S-262 31 Ängelholm

On Compuserve contact:

Stefan Rehnberg
S-260 91 Forslöv

Send orders or shareware donation to any of the addresses above.

Component list for SimCom© Mark I Rev.2

						ELFA part no, for Scandinavians only.
No.				Value		ELFA nr.	(ELFA alt.)
R1,2,9,17,18,22,23		10K	
R3,4,14,15			1K	
R5,6,16,19,20,21		820K	
R7,12,13			100		
R8				47			
R10				470K	
R11				18K					
R24,25				8,2	
R26,27				47K	

C1				100n		All cap. < 1u are polyester, => 1u are electrolyt.
C2				22n		All are standing vert. 2 modules, 5.08 mm (0.2") 
C3				4,7u
C4				1n
C5				470n				
C8,9,11,12,13,19,22		100n					
C6,14,15,20,21			1u	
C7				2,2n
C10,18				10u				
C16				47u						
C17				470u/25V	67-009-34

P1	220K Horiz. Trim, Mic gain		64-363-03		64-371-07
P2	50K Horiz. Trim, Noise level		64-362-40		64-370-81
P3	100K Horiz. Trim, SB level		64-362-73		64-370-99
P4	10K Turn stereo, line volume		64-095-36		64-105-34
P5	10K Turn stereo, out volume		64-115-16		64-125-14

D1				AA119		70-018-94		
D2-10				1N4148		70-005-57		Any diod

B1	Rect. bridge 6 pin DIL			70-084-02		70-084-51

IC1	LMC660, 14 pin DIL			73-660-24
IC2	TDA7050, 8 pin DIL			73-063-35
IC3	7806, TO220				73-091-56		73-090-65
J1,2	3,5mm stereo outlet			42-700-47
J4,5	Plint, Line connector			48-379-28		48-375-06
J6	9V Battery connector			42-042-02		42-041-78

RE1	Relay 5VDC DIL 				37-043-50		37-072-13
RE2,3	Relay 5VDC				37-053-08

TR1,2	600 ohm Line transformer		56-562-51

	Button, PTT				35-305-40		35-306-49
	3,5mm stereo outlet, SB in		42-700-05		42-700-62
	Thin stereo cable, SB-SimCom(c)		55-806-00		55-806-18	
	9V Battery or 5-12VAC/7-16VDC adaptor	Chassiconnector for AC adaptor, J6		42-050-92		42-050-50
	Headset, with condensor microphone

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