Replacement 2879's

[Tokin]

Well time has shown us that the Chinese transistors are not as stout as their obsolete Japanese counterparts.
As much as I don't like Bbi his video dismantling Toshiba and Chinese Toshiba knockoff transistors is good stuff. I think he compares the pp100 in that video also. Scary to think of how many fakes could be out there considering how much some folks want for used pills. Testing before buying will help I guess.
With that said hg is producing the 2879C series that they rate at 150w. Some builders have been trying them with good reports but they still won't handle the abuse Toshiba's did. I think the 2 keys to a good amp with Chinese pills first is the builders knowledge and attention to producing a efficient amp. 2nd is moderate operation.
From what I've learned here and elsewhere is if you want a new 4 pill buy an 8, reduce your input drive, idle the amp and run it at 12v. Don't forget to give it lots of air. It's been said a hundred times here and I'll gladly repeat that heat kills.
That should pretty much ensure your investment won't go up in smoke anytime soon no matter what transistor you're using imo.

 

[2NC995]

I’ve been happy with my DEI amps and so far have no complaints. 8 months on the DX500, and a month or so on the DX1600. About 100 watts peak per device, and no complaints. While that may not be enough to keep some folks happy...I’m good with it.

It takes a lot less drive to reach those levels than I’d have ever guessed.

I wouldn’t expect them to withstand high heat, high drive, or high SWR. Short of those conditions, all seems to be working fine.

 

[9C1Driver]

So your running both of those amps at 100 watts peak? Is this on SSB and what are your input wattage levels? Just curious.

When you say per device do you mean each amplifier or each final in the amplifiers?

 

[999]

So your running both of those amps at 100 watts peak? Is this on SSB and what are your input wattage levels? Just curious.

When you say per device do you mean each amplifier or each final in the amplifiers?

He means peak output per transistor.

 

[2NC995]

Right. Per transistor, and SSB only.

So, 400 watts for the DX500, and 800 for the DX1600.

It’s actually slightly more with the truck running, and less with it off.

I drive the 500 with 12ish watts, and 30ish into the DX1600.

The DX1600 ran like that, with truck running and holding voltage, shows about 900 watts at 100 amps draw...measured with a tone into mic and with a dummy load.

In reality, I could contact anyone I heard on the 500 even just cruising it easy. I feel that sometimes now there are more stations that copy me that I cannot hear.

But, I just wanted a 1600, and had another application for the 500 so I went for it.

 

[Radioman56]

The MicroSemi, MS-1051 is a quiet good / rugged replacement for the Toshiba's (FYI: Actually, the non red-dot Toshiba's were better than the red-dot devices, as they had Beryllia-Ceramics for better chip to substrate heat transfer)., though the MS-1051s are a bit "pricey" ($50+ ea.) as compared to the poorly made HG / DEI devices...
(spec sheets & internal photo captures attached., as there are NO actual factory spec-sheets to be found for the HG / DEI devices...)

 

[Shadetree Mechanic]

The MicroSemi, MS-1051 is a quiet good / rugged replacement for the Toshiba's (FYI: Actually, the non red-dot Toshiba's were better than the red-dot devices, as they had Beryllia-Ceramics for better chip to substrate heat transfer)., though the MS-1051s are a bit "pricey" ($50+ ea.) as compared to the poorly made HG / DEI devices...
(spec sheets & internal photo captures attached., as there are NO actual factory spec-sheets to be found for the HG / DEI devices...)
View attachment 38790 View attachment 38791 View attachment 38792

Looks interesting. Where would be a good place to get them from?

 

[Ranch55]

I imagine they will be just as difficult to get as original Toshiba transistors.

 

[Tokin]

I imagine they will be just as difficult to get as original Toshiba transistors.

Yeah, looks like another long obsolete part, no thanks. My choice is the hg 2879C. At 150w pep i can loaf along and never strain the amp. Yeah ill need a bigger supply but so be it.

 

[snippits75]

Most of the builders I know about are using HG's, so there must be a good supply of them. Online prices are reasonable, and they can be bought direct from HG through their Ebay store.

I do wonder what Texas Star is up to by installing Toshiba branded transistors in the latest amps.

 

[Tokin]

I do wonder what Texas Star is up to by installing Toshiba branded transistors in the latest amps.

Up to losing a bunch of customers. They could at least sand the fake branding off the pill.