[Test-Equipment] PS Filter Caps for Model 105 Function Generator??

[Barry]

I have a WaveTek Model 105 function generator and I posted this to the 
WaveTek Yahoo group but thought I'd post it here as well.  I realize not too 
many folks here might be familiar with this particular unit, but I think the 
question is a pretty basic one.

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My 105 function generator has developed a problem. When the frequency 
control is turned to nearly the lowest value, it stops oscillating. To get 
it to start oscillating again, one must turn the frequency control to a 
higher setting and then rotate the "Square Wave Only" attenuation control.

I'm not sure what else is going on, but it got me to looking at the power 
supply as a possible problem. It has original electrolytics in all four 
places (+/- 8V and +/- 13V supplies). I don't have a 'scope, but monitoring 
the output under load with my DVM's AC setting, I'm seeing about 100mV on 
the 8V supplies and a bit less than that on the 13V supplies. I realize it 
isn't a sine wave so the RMS reading is not accurate, but it give me some 
indication of the ripple that's present there.

I've thought that the caps may need to be replaced and that might help the 
overall problem but not sure. Given the load and the original values, the 
supply should have some ripple on it and it got me to wondering how much 
ripple would be acceptable. I can replace these with much larger values with 
room to spare and it will reduce the ripple significantly; however, I wonder 
if this is just a waste of time.

Any thoughts on this? Given that the caps are 45-ish years old, it stands to 
reason they may not be healthy, but then again, they just might. I'm just 
wondering how much ripple would be acceptable on the various circuits in the 
105.

Thanks,
Barry - N4BUQ