I Really Blew It!!!

[OverLoad]

Side wings on OE tr's are very soft and flexible.

That may be so but you only need about 8 inch pounds of torgue to tighten TO-220 case transistors.

 

[Hat Alto]

OK, I am under that. Been jetting carburetors with similar torque limits. Guess I'll find out. I have spares. Thanks for info. Who knew?

 

[OverLoad]

There is no way in hell that you will bend the tabs on those transistors under 8 inch# of torque; especially to the extent that you have. I'm not gonna argue with you over it however.

 

[Hat Alto]

You just did, but thanks anyway for the info.

 

[hercman]

Transistor mounting



This an old thread but jic anybody is searching this like I did. Here's how I mounted replacements for the "batwing" NEC TR's using the old TR's as hold downs:

Replacements in this application are MJE15033G+32G from Mouser. Cheap fix, sounds ok to me, we will see how it holds up. Used old insulator thing with no trimming, cleaned and new thermal paste Mounted w/soft zinc panhead#4 1/2" machine screws into the harder alum. heat sink.

Holy Crap Batwing! Did you use a cheater bar to "torque" that?

 

[KingBubba]

I was going to try that, but I only blew one pair. I made an aluminum strap to fit. It worked fine.

 

[Robert.garb]

Hello King Bubba. Nice job on your repair!! Did the protection relay pick up after you put in new outputs? I have just read through this entire post. I am in the process of fixing a Kenwood KR-5600 which uses the same output transistors (2SB618 and 2SD588). Why did you choose the on semi MJE over other sub's? I am wondering because I need to order sub's myself now and want to get the best ones possible. Any help from you or anyone else would be extremely appreciated.

 

[petehall347]

those subs are ok ..i have used them before in 2 different make amps . and if using old transistors for holding down the new ones they do tend to bend a bit . this doesn't matter one bit .
i did also use different drivers ..bd139 bd140 .. i like those ones .