T03 vs standard 3 lead transistors

[avionic]

2SA1117/2SC2608
TO-3
200V
17A
200W
20mhz



YAMAHA PC5002M
10 pairs per channel

 

[Gibsonian]

That's just bragging Dave....

 

[avionic]

That's just bragging Dave

 

[tarior]

I believe the TO-220 was specifically design to replace the TO-3 and TO-66. I don't recall the reason being stated in the datasheets and ref guides and I've scanned what was published there.

View attachment 1317816
View attachment 1317817
View attachment 1317818

TO-220 was designed to replace TO-66, TO-3P is meant to replace TO-3.
With a little (or in some cases, a lot) effort, pretty much all TO-3 BPJ transistors can be replaced with modern, often superior, devices.

 

[tom3]

If you might have a car stereo amp that has blown up you might find some replacements for the taking. I tried these and they do work fine, current adjust fine, sound good, run nice and cool. Not real pretty, not great for a detailed restore, but can't see them anyway.

 

[Hipocrates]

In some cases that you need high frequency outputs, you can put TO3P devices, other wise I don't see why not to use Onsemi.

Photo credit to ilimzn on diyaudio.com.hr

 

[tarior]

TO-3Ps may not look beautiful in place of metal cased devices, but at least you can get real-deal SanKen, Toshiba, and ST Micro transistors.

 

[avionic]

Going this route. The ring connectors will need to have plastic bushings as well, To insulate the collector lead from the heatsink.

 

[Hipocrates]

Going this route. The ring connectors will need to have plastic bushings as well, To insulate the collector lead from the heatsink.

Good call! I forgot to mention it

 

[gslikker]

Nice solution, using the connector pins!

 

[Racingh11]

View attachment 1319048

2SA1117/2SC2608
TO-3
200V
17A
200W
20mhz



YAMAHA PC5002M
10 pairs per channel

Looks expensive if it has a major failure. I guess the question is; what are you welding? lol

 

[avionic]

Looks expensive if it has a major failure. I guess the question is; what are you welding? lol

Whatever needs welding


PC5002M
Power output: 500 watts per channel into 8Ω (stereo), 1500W into 8Ω (mono)

 

[rcs16]

TO-3 is a hermetically sealed package, so it will pass the pressure cooker test better than a plastic package will, so it is deemed to be more reliable but who runs their equipment in a pressure cooker?