sleddog83
XS650 Addict
Didn’t seem to be much point in removing them and checking them on my cap meter without knowing what value they should be. The meter could tell me anything but how would I know if it is correct. Besides, odds are that after 36 years they have gone resistive anyway. Even if they are shorted or open, what value of cap should I install? I suspect the value is significant, given that the resistors attached to the IC seemed to have been selected for a specific value. This might imply that some tuned RC values were selected for op-amp circuits in the IC.
I have been looking over the TID12-01 igniter I bought off eBay(supposedly from a 1980). For the IC it uses a quad Op amp IC.(ha17902). The board is filled with components that are connected to at least three of the op amps. I suspect the busted TID12-03 igniter I have is essentially the same quad op amp IC with all the extra caps and resistors built into it. Hitachi basically custom built that IC and reduced the component count on the board. The older board also has two tantalums on it. I will check those first. I will also trace out the older board to see if can figure out what the op amps are configured to do.
I have been looking over the TID12-01 igniter I bought off eBay(supposedly from a 1980). For the IC it uses a quad Op amp IC.(ha17902). The board is filled with components that are connected to at least three of the op amps. I suspect the busted TID12-03 igniter I have is essentially the same quad op amp IC with all the extra caps and resistors built into it. Hitachi basically custom built that IC and reduced the component count on the board. The older board also has two tantalums on it. I will check those first. I will also trace out the older board to see if can figure out what the op amps are configured to do.