Benjolin critical resistor values.

[okelk]

I've got a nearly finished benjolin on my bench, but I don't have any 510 ohm resistors.

Are those values critical or could I just take a 560 ohm resistor?

...I guess otherwise I'll have to improvice with some resistors in series/parallel...

[electrotech]

According to the SSM2164 datasheet, those resistors are there for stability reasons (datasheet specifies 500 ohms).
So it might work perfectly OK using 560 ohms or it could be unstable, however I've no experience with a SSM2164 so don't know how fussy it is...
so try it and see !
Other than buying some 510 ohm resistors, one solution would be to use your 560 ohm resistor with a 5.6k resistor in parallel - this will work out to 509 ohms.

Hope this helps.

Andy

[okelk]

hm... thanks.

I just found a filter design based in the ssm2164 that uses 560 ohm resistors, so it's probably ok...but to be on the safe side i use a 390 ohm and a 120 ohm in series

[siri]

Hi, don't want to start a thread just for my question, as it's a part question.

Parts lists call for a BC547BP... I can't find it anywhere... SSM2164 is widely available in comparison...

Will a BC547B do the job?

[electrotech]

Yes, that part will be fine.

FYI
BC547 is the transistor type, the 'B' is the gain group.
Different manufacturers use different letters at the end, usually to specify how they have packaged the transistor i.e. loose/banded or with pre-formed leads etc.

Andy

[siri]

thank you!