Fisher tone and phono PEC capacitor replacement help

[mp53]

I'm wanting to replace tbe capacitors and resistors in those tone and phono networks in my Fisher x100c. So I ordered some Wima PFK 2 types rated at two and a half percent. Wima says these types are good where polystyrene types are used. But when I measure the capacitance they all measure a little low, for example the 390 pf will measure out 360 pf about. Now I also have some 22 and 30 pf polystyrene in my old stock and they measure a little low to. Am I safe to assume that the discrepancy is in my meter and there is no need to trim the Wima's with the polystyrene's? I'm assuming that all these network components need to be spot on. Any input is appreciated. MP

 

[fred soop]

Is it an expensive meter or an el cheapo? Is the meter battery wearing down?

My Wima 390 pF and 820 pF are 5%, not 2.5% like the other values. Mouser does not list a 390 pF 2.5%. DigiKey does not even list a 390 pF at all. Look on the side opposite the value and it will be marked "5" or "2.5".

 

[mp53]

I didn't spend much for the meter but it's been constant and reliable, seams to be well made. I'll check battery.
Funny thing the 390 Wima says 5% on the package but the capacitor says 2.5. The 1500 ones say 2.5% on the package and 5 in the capacitor.

 

[fred soop]

Interesting. Maybe I should look at mine again as my rolling inventory is updated from invoices, not the actual devices. Maybe mine are 2.5%.

 

[fred soop]

Checked my Wimas and all 0.033 and lower are 2.5%. That includes the 2 values that were cataloged as 5%. Actually, that's good news. There are Panasonic polypropylene caps at 3% from 0.0022 to 0.47.

 

[mp53]

Well I put a new battery in my meter and they are all reading close to the stated value. But the tolerance stated on these capacitors mean how much the capacitance can drift at a certain temperature right , not how close it is to the stated value.