Installed bias transistors wrong. 2N5088 compatibility?

[Jess]

Mistakes where made. I failed to look at the thermal band straps when we were building the boards so they got installed flush and where trimmed before I realized the error of my ways. The leads are now too short to make the bend so I'm going to need new ones. The BOM says 863-2N5088G by On Semi were used but Mouser (and Digikey) lists that part as obsolete and suggests 610-2N5088 by Central Semiconductor as a possible alternative. I noticed that the base emitter voltage is different. Does anyone know if this part will work?

 

[FredR]

RoHS compliance is indicate by the letter “G” after the lot marking. Central Semi is unknown to me. I expect it would work fine.

 

[laatsch55]

Central builds good shit.

 

[mlucitt]

I bent my bias transistor leads into the nearest holes (2N3403) because I could not read the silkscreen printing. I caught the mistake during a QC check and managed to relocate the leads to the 2N5088 lead holes where they were soldered. Nice that the Backplane Boards allow both types (and pinouts) but first-time installers may make the same mistake I did by not looking closely, or under a magnifying glass. Maybe a short paragraph after step 18 (PL400 Assembly Notes) in the instructions would help:

"Remove the original 2N3403 bias transistors (Q6) from the heatsink straps and insert the new 2N5088 bias transistors with the leads facing away from you and the screw hole on the right. Secure the transistors into the heatsink straps with a drop of superglue to help the heat transfer process.
Install the two new bias transistor assemblies onto the Backplane Boards with the leads going to the "5088" solder-through holes and solder in place, after aligning the heatsink strap over the silkscreen outline on the Backplane Boards."

Thoughts?

 

[Jess]

Something like that could help. I get that these are for experienced builders and, to be honest, I probably wouldn't have attempted this if it weren't for my cousin who does this stuff for a living. We had a pair of microscopes and two stations and we each handled a backplane.

I knew I needed to salvage the thermal bands but I just assumed it was a heatsink I'd just pop on and I never even looked at it. Which, is 100% my bad I'll admit. But if there was a photo of the transistor installed in Step 6b or an expanded description I might not have missed it.

 

[WOPL Sniffer]

well, the bag is marked 5088 and the board has spots for two transistors and they are both marked

?????

 

[Jess]

well, the bag is marked 5088 and the board has spots for two transistors and they are both marked

?????

Don't get me wrong, the packaging, the printing, the documents are absolutely outstanding. The second I opened the box and saw how neatly everything was done I immediately wanted to buy more WO products.

I put the correct transistors into the correct spot I just missed the part where they needed to be mounted higher so they could be bent into the thermal bands