Subs for 2N5952, 500K pots...

[Danny G]

I'm building a Phase 45, among other projects.  I need a matched set of 2N5952's, but can't find them locally.  The Tonepad.com layout says other FETs will work.  Any suggestions?

Also, I need 500K Log (A) pots for the Phase 45 and for the TS-808 I'm also building.  I have two left over 500K Linear (B) pots--will those work?  My TS-808 is complete but not working... just wondering if the 500K B pot has anything to do with it.

Thanks!

[RDV]

About any matched JFET will work in the Phase45.

A pot is a pot, however you may not like the range of a linear when an audio is called for.

The TS has another problem.

RDV

[Danny G]

I'm a noob.  Not sure what JFETs are.  If you could enlighten me, that would really rock.  And also let me know some other tranny's I could put in that Phase 45.  It's for my wife, and her B-Day's coming around!

Thanks

[R.G.]

I need a matched set of 2N5952's, but can't find them locally

I highly recommend the 2N5485, from the days when I could not get 2N5292s. However, both are available from Mouser Electronics for about $0.30 each these days. You might get away with 2N5457, which is pretty common. Some of them will work.

You can match unmatched JFETs with the JFET matching circuit shown at GEO (which you'll wind up needing to read for your other questions anyway.) Yes, they have to be matched.

Not sure what JFETs are.

Junction Field Effect Transistor. They work by having a conductive channel between the drain and source leads. A negative voltage on the gate lead progressively chokes off the channel like a garden hose being squeezed.

If the gate is driven positive with respect to the channel, the PN junction that insulates the gate from the channel is forward biased, and the gate conducts into the channel, causing incorrect operation.

[RDV]

FieldEffectTransistor

J201, 2N5457, MPF102 are the most common and easily found IMO. You can even find MPF102 at Radio Shack, but I think that the 2N5457 might be the better of the 3 for the PHASE45.

The thing is that you have to buy around 10 or so to find the majic 2.

I just bought a 30 lot of 2N5457 on eBay for $5.00 plus shipping. Not a bad deal. He's got more.

Here's a link: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4666&item=3825946850&rd=1

RDV

[RDV]

Same guy has 2N5485 also:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4666&item=3825918472&rd=1&ssPageName=WDVW

RDV

[Fret Wire]

A 500k rev. log pot will work the best in the phase 45 & 90. It was used in the originals.  Like RDV says, a pot is a pot. You'll just find that the rev. log works the most "normal" to what you're used to.