Separating H/V syncs on 8Liners chassis

[M3talhead]

 I've got an 8Liners board and want to rig up my new act-labs gun, but first need to re-wire my signal cable. Currently I have the H/V syncs combined, but as everyone who owns one knows, Act-Labs guns require the syncs to be separate. There is a jumper on the board that allows you switch between the 2 settings, but only one factory installed set of pins to attach the input cable to.

Aside from directly soldering the cable to the chassis, does anyone have any ideas for installing pins and using a connector? Has this been done before? (The signal points for separate syncs is the row of 6 holes next to the white connector)

[Ken Layton]

When I converted an old Nintendo Sharp monitor with this 8liners (made by Jen Shinn) chassis, the first thing I did was unsolder that phoney baloney 5 pin connector and replace it with the normal video connector all USA monitors use. You want Mouser Electronics (www.mouser.com) part number 571-6404456 (Tyco/AMP brand) or # 538-26-60-4060 (Molex brand). I believe Bob Roberts carries these connectors too.

[M3talhead]

Thanks Ken! I'll pick one up and install it as soon as I get settled in my new house.

[spun10th]

Hi, this is the exact info I was looking for as this is now the only problem I have with my 8liners monitor (jenn shinn).  I ordered the connector as listed by Ken, but has anyone verified that the Actlabs gun works once the syncs are seperated?  Thanks.

[M3talhead]

Hey Ken,

Whats the part number I need for the female version of the 538-26-60-4060 Molex connector?

-Metal

[Ken Layton]

538-09-50-7061 for the female version. Of course you'll also need 538-08-50-0106 terminals to go inside it.

[spun10th]

Hi Ken,

I have done some more testing with the Jenn Shinn chassis and the Act labs light gun.  I have tried soldering a jumper wire to the chassis PCB (underside) connecting the H and V sync leads, then changing the jumper pin accordingly, however, still no go on the lightgun.

After rethinking this a bit, I not sure how the state of the syncs (seperate or composite) at the actual monitor chassis, would effect the lightgun.  My logic is this, the ActLabs VGA box is connected directly to the vieo card, then a VGA cable goes out from the VGA box and into the J-pac, then obviulsy out to the monitor via R,G,B,Gnd, and composite sync.

Considering that the VGA box is before the J-pac, the H and V signals are still seperate at that point, they are combined via the j-pac into a composite signal per Jamma standard. 

Am I off base here?  Is there anything else you can think of that would stop the light gun from registering shots on the Jenn Shinn chassis?  Thanks for your time.  Your help and expertise is much appreciated.

[StephenH]

I read that J-PAC does NOT combine the syncs, according to Ultimarc.com.   My theory is that the gun decoder reads, but passes through the sync signals to the output, and does not buffer them, but reads them live.   I wonder if connecting them together causes the readings to be off, due to the fact that that it they are simply being passed through. 

 You might try disconnecting the gun decoder, and take an ohmmeter, and see if there is a dead short between the HSYNC pin on the input, and the HSYNC pin on the output.   Repeat the test on the VSYNC pin.   If this is true, this is why connecting them together on the output side is causing the readings off.   My personal theory, is that the HSYNC input pin is jumpered to the HSYNC output pin inside the gun decoder.   I beleive the same is true for VSYNC.  The pins in question are 13 and 14.


Also, I found this link, which might do what you need:

http://www.si87.com/Products/Cabling/Adapters/cs1spec.html