Secondary trigger type ID from PCB?

[wazzu70]

Hello, I am trying to identify if my unit is equipped with a VR or Hall secondary trigger. Im having trouble finding documents on the VEMS site showing what each configuration would look like.

If anyone can help, that would be appreciated!

[GintsK]

Take a look here:
http://www.vems.hu/wiki/index.php?page=GenBoard/Manual/InputTriggerHardWare

[wazzu70]

Thanks for the reply. I was looking at that page, but I cant make sense of the secondary trigger information. For the primary trigger its good and has a good picture reference. I have a hard time telling which bullet applies to what configuration. Maybe its just me 

Where can I find where LM1815 is on the PCB?

[GintsK]

There is three key pictures on this page....

May be you can take pictures of your PCB?

[wazzu70]

GintsK, thanks for your help as always!

I looked further down the page at the older board revisions and think I found what I need. I will post up pictures of my PCB and the section on the page I am following. People can let me know if I understand correctly or if I am way off base

[wazzu70]

I do not have a picture of my board, but this picture shows what mine looks like:

http://www.vems.hu/files/ErikEnglund/pictures/IMG_0013.jpg

The solder blob circled in the picture is present on my board. I do not have a wire from EC18pin12 to anything.

This is what I was following from the website:
     

while SJ7 is open, with cam-HALL masking signal unconnected you can measure that R48 (2k7 recommended) pulls up D27 cathode to 3.5V or higher. This is a good verification !
        after SJ7 is shorted, unfortunately this cannot be measured (except with scope with input pulses applied)
    SJ7 solder-blob on the bottom, so LM1815pin12 output is connected to the microcontroller input pin. This blob is on the bottom, under the FETs.
    solder the 2nd LM1815 (same orientation as first: pin1 closest to atmega)
    wire from EC18pin12 to the 2nd LM1815 input pad (that goes through a 18k resistor to pin3 of the second LM1815)
        1k pulldown resistor between VR input signal and GND
        this is effectively in parallel with the VR sensor. Scratch the green solderprotect a bit at the GND so an SMD resistor can be soldered
    To make it work with the 1k VR-input pulldown resistor, connect LM1815 pin5 to +5V with the SJ4 (3pin jumper): solder the mid-pin to the +5V pin that goes LM1815pin8
    R182=0 resistor (or short) at LM1815pin7. This helps the adaptive hysteresis (quicker charge). Has the same function as R181 >= 100k for the first LM1815 (soldered in factory) but 0 Ohm (short) is more appropriate here.
        optionally increasing the neighboring 220nF capacitor by adding an additional (solder piggyback) +1uF or +2.2uF might be a good idea

[GintsK]

This blob is used when secondary is VR.

[wazzu70]

Does the V3.6 board need the wire from EC18pin12?

I suppose a picture of my actual board will be helpful. Hopefully I will post it up this weekend.

[GintsK]

3.6  - no.
VR input on 3.6 is ec36-13. (except Auditrigger)
But anyway wire is required from trigger SJ to secondary LM1815 input. That blob connect output of LM1815 further in way to microcontroller.

[wazzu70]

Some pictures of the board (V3.6) #2734.

Top:


EC36 closeup:


EC18 closeup:


Bottom:


What I think is secondary trigger circuit area:


Primary circuit area:

[GintsK]

Yes, secondary is VR.
But I also see one mod and one production error in last picture.

error: bottom capacitor in middle: it should be mounted perpendiculary as it is now. Some batch of boards had this error. But in most cases these boards do the job.

mod: same picture, middle - there is resistor. Seems 250 Ohm (?). In past there was no resistor at all. Now boards come with 1000 Ohm resistor. There is place for it alongside with mentioned cap if it is mounted correctly.

Probably board will be operational as is. But in case - for you to knew.

Gints

[wazzu70]

The VEMS shop got back to me and confirmed the secondary trigger on my board is configured VR.

Thats what I needed, so I am happy!

Now just need to figure out why trigger analyzer did not have a secondary trigger trace.