ssr01 wrong output

[tamu]

Hi all, I finished building a ssr01 to power my gamma2 dac and its the 5v version. made sure I used all the parts specified in the bom.

I when I first turn the power on the DZ1 led briefly flashes and I get only 3.4v out which fluctuates a bit around 3.3 and 3.4v.

opamp pin 2 has .74 and pin 3 has .79
pin 7 is at 1.02v
my first suspect is q3 but I will check all the transistors just to be sure..

Any other ideas would be more than welcomed. :-)

[peranders]

How much is your input voltage? For 5 V out you must have at least 10 V in if you have the LM317 installed. Are the SENSE inputs connected? Which opamp du you use?

[tamu]

Ive got a 9v 15va trafo..

sense inputs are not used (j1 and j2 are soldered)

opamp is ad825

[peranders]

Have you used my BOM for 5 V?
If you measure your input voltage, how much is it?
R5 in place, not R6?

[tamu]

Yep used your bom.
Trafo is 11v unloaded
R5 is in place. No r6 resistor

[peranders]

The opamp is placed correctly?

If you remove the R5, does the collector voltage of Q1 increase?

DZ1 is a LED and placed correctly?

[tamu]

The opamp is placed correctly?

If you remove the R5, does the collector voltage of Q1 increase?

DZ1 is a LED and placed correctly?

yes

I dont know I will check that later

and yes.

[tamu]

sorry for the late reply..

So I removed the r5 and on q1 collector pin I have 14.4 pin 2 has 1.4 pin 3 had 9.2v

[peranders]

It seems that the AD825 is broken. Is R5 really 47 ohms, not 470 ohms? Was the opamp placed correctly?

[tamu]

it could be.. Ill check what opamps I have and see if any is suitable.

I checked the resistor again and Im sure its 47ohms.

[tamu]

ordered a couple of ad825 opamps. will replace the one on the board and see what happens.

thanks for the help so far peranders. much appreciated.

[tamu]

swopped the opamps and still no change..

[peranders]

Have you used my BOM to 100% or are some parts changed?

[tamu]

the only thing different is bc556 transistors.
I couldnt find the "c" version so I got the "b" ones.

[peranders]

The B, C thing should be a problem. Could you send me a couple of close up pictures?