Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => The Newcomer's Forum => Topic started by: AllThorUp on September 03, 2016, 08:49:01 AM

Title: MPSU07 & MPSU57 alternatives?
Post by: AllThorUp on September 03, 2016, 08:49:01 AM
Anybody able to point me towards some alternative replacement driver transistors for this pair? (MPSU07 & MPSU57) Those 2 are a little pricey, and apparently arent made anymore, so i was hoping to find an alternative that was a bit more cost effective. Thank you, I appreciate it very much.
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: nickb on September 04, 2016, 11:29:15 AM
Well I'm not ignoring you but I don't have an answer either.  I haven't come up with anything suitable in a compatible package, or even a SM package for that matter. Can you relax the specs e.g do you really need 10W @ Tc=25C?

Title: Re: MPSU07 & MPSU57 alternatives?
Post by: Vitrolin on September 04, 2016, 01:57:06 PM
where are you going to use them?
without that information it will be hard to find a substitute..
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: Enzo on September 04, 2016, 03:49:51 PM
Any reason a TIP31C and TIP32C wouldn't work?  The legs are in different order, so you turn the part sideways and bend the legs to suit the holes.   

I might also try MJE243 and MJE253, again, the legs are in different order, but that should not be a problem.
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: Enzo on September 04, 2016, 09:30:14 PM
OK, where are you located?  And how many do you need?

I just did inventory on my transistor stock, and the "case 152" series I have a few.

I have ONE MPSU57 equivalent in the Motorola HEP series NOS.

I have TWO MPSU07 NOS, and one equivalent NSDU07 also NOS.

If those few will help you, I will let them go cheap.

And the others I have with amounts:
MPSU06 - 17
MPSU10 - 7
MPSU45 - 3
MPSU60 - 2

Those are not rally related to the 07/57 pair, but I have no idea what you are working on.
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: DrGonz78 on September 05, 2016, 12:39:42 AM
Quote from: Vitrolin on September 04, 2016, 01:57:06 PM
where are you going to use them?
without that information it will be hard to find a substitute..

Lets play the guessing game??? Polytone??  :duh :duh
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: J M Fahey on September 05, 2016, 08:04:32 AM
IF they are to be used in a Polytone, most any transistor same case and standing some 80Vce will be fine, because 2X rail voltage does not reach that.
Meaning many of Enzo´s will work fine, just doublecheck datasheets.

Wouldn´t trust EBay purchases.
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: AllThorUp on September 09, 2016, 02:05:55 AM
I am repairing a pignose 30/60, i have replaced the output transistors and next on my list is to replace the drivers. Sorry it took a little while to reply, ive been away from home.
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: AllThorUp on September 09, 2016, 02:09:31 AM
Enzo, I am located in california, and unless i mess something up (fingers crossed) i only should need 1 pair..  thanks for the offer, i would be extremely pleased if you would sell them to me for a good price!
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: Enzo on September 13, 2016, 09:17:48 PM
Then if you haven't already, send me a PM about this.
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: Enzo on October 02, 2016, 01:25:03 AM
I was laid up for a couple days, but I did get your parts mailed out Friday.  You should see them soon.
Title: Re: MPSU07 & MPSU57 alternatives?
Post by: AllThorUp on October 03, 2016, 04:42:23 AM
Thanks, Enzo. I really appreciate it!