OC79 Hfe Values

Gathering parts for my upcoming Mystery Machine build. I have 2 pairs of OC79 transistors. One pair has a Hfe of 70 and the other pair has a Hfe of 50.

Would it be advantages to use one set or the other for my build or mix them, using one of each?

Thanks!
 
I think the easiest thing to do is to socket and test various combinations (it’s only 4 combinations!).

Edit: scratch that, I didn’t realize they are used as diodes as Chuck pointed out.
 
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They're being used as diodes in the MM, so HFE doesn't matter. Personally, I'd save the OC79s for a pedal that requires transistors and use any old Ge diodes in the MM. Socket them if you wanna try different ones, but the diff should be minimal. When using diodes in the MM, connect cathode to pin 1, anode to pin 3.

Looks like C9 is backwards on the schematic, although the DC voltage across the cap is so small it probably doesn't matter.
 
The Hfe (or "beta") of a transistor is a measure of its current amplification capability. In general, a higher Hfe value indicates a more powerful transistor. In your specific case, using the pair of transistors with an Hfe of 70 would likely be more advantageous for your build, as they will provide more amplification than the transistors with an Hfe of 50. Mixing the two sets of transistors would not likely be beneficial as the difference in Hfe could lead to an imbalance in the circuit.
 
Thanks all for the replies. Unfortunately, I had already completed the pedal by the time I had received any replies. I did come to the conclusion to try both values in the different positions. The problem arises is that listening to the results in one position, by the time you change out the transistors and re-test in another position, you really can't remember what the other sounded like. The results I concluded was that all the positions sounded OK regardless of their orientation in the circuit. Realizing now from Chuck's post that their being used as diodes, it's obvious to see why I came to that conclusion. 😆

P.S. You can now view my completed pedal in the build section.
 
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