Re: Suspect Parts


nm0s_qrp <ai9e_qrp@...>
 

The tolerance for these ceramic disk capacitors is -20%, +80%, so  50% high is within their spec.  These parts are applied in circuit functions where their value, dissipation, and leakage are not critical.  Unless a component s is faulty, like your experience with C9, the parts supplied with the kit are entirely satisfactory for their intended use.  
As far as counterfeit semiconductors go, the 2N3019 transistors used in the Ozark Patrol were, until recently, old stock from 20+ year old inventory, and not suspect.  Since that supply has dried up, we now use parts obtained from a reputable supplier.
Speaking from personal experience, and having obtained a LOT of components from different sources, the biggest problem with counterfeit parts so far encountered were the 2N7000 transistors purchased for the Cricket kit.  The first batch of 'no-name' parts purchased proved to meet all published specs, but had far lower RF gain than parts from ON Semi or ST.  But, RF gain is NOT a specified parameter for these parts, so the still met 'spec', but were unusable for the kit.  So, I have a box of a couple thousand of them waiting for an application where RF gain is not critical.

73 Dave NM0S

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