[sdiy] SAJ110 help please

[Bob Weigel]

On 6/18/2010 6:49 PM, Oren Leavitt wrote:
>
>
> Bob Weigel wrote:
>
>> Voltage is -7.7V on pin 1
>
> Bob,
> That -7.7V seems off. The Solina SE service manual specifies -9V to 
> the SAJ110 dividers.
> The low voltage could be causing the logic high/low threshold of the 
> SAJ110 input to be borderline with the input signal to the dividers.
>
> I would double check all of the the power supply voltages against 
> those called out in the service manual. Especially since the Solina's 
> power supply is unregulated and uses hot-running resistor dividers to 
> get the various voltages needed.
>
>
> HTH,
> - Oren
>
>
I should have added... I tweaked it down a bit because that was the 
optimal for the chips it seemed.  Maybe I've just somehow run into 
multiple scrap units that all have crummy marginal chips?  The only 
thing is..like I say..most of these worked in a crumar Organizer 2 I 
tried a lot of them in just to see what was up!  It's like..only in 
*this* environment do they need to be handled more carefully or 
something :-)

Anyway thanks..I should have noted I only have the version of SM that 
has the 11V supply to the SAA1005 which is the earlier design I 
believe.  Absolute max on the SAJ110 is 11V so we don't want that. -Bob

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