Marshall preamp problem

[Miladinovic]

Hello everyone, newbie here. I have a Marshall 8280 valvestate from the 90’s. The preamp has some obvious heat damage to some transistors. The factory installed an 4.6k resistor where the Marshall schematic shows a 8.2k should be. The transistors downline got smoked. The part numbers on the transistors is VN2410L. It’s a Motorola part number. I can’t find these damn things anywhere. Does anybody have any insight where I might be able to find these components? Thank you all for any help. Take care. -Ethan.

 

[Kamanda~SD]

Re: Marshall preamp problem

Readily available from mouser or digikey

 

[devastone]

Re: Marshall preamp problem

https://www.findchips.com/search/VN2410L

 

[Darg1911]

Re: Marshall preamp problem

Yeah, these are easy to find. But I wonder if the OP is looking for the original Motorola's? If so, good luck. It's pointless but there is probably some surplus out there if he really has to have Motorola and doesn't mind paying extra for the same part.

 

[Adieu]

Re: Marshall preamp problem

Wow real resurgence of 8280 interest all of a sudden here...

What's the situation with the amp at this time? Slightly crispy and detrimental to the flavor, or all-out smoked? And are you fixing it out of curiosity/to learn, or for cost effictiveness? Cuz depending on how far it burned through, and taking into account their low low market value...

Definitely wouldn't bother paying extra for original parts. Replace with whatever equivalent comes up cheap and doesn't gouge you on shipping imho (known big brick and mortar places for electronic components only still exist in like 3 cities in America... unless some of the othes are so analog oldskool they have no web presence at all)

Also if you're getting into electronics repair on the cheap, you might look into getting an assorted grabbag of cheapo resistors and scavenge other stuff from VCRs or whatever... apparently 1000 resistors cost barely more than 5 resistors, if even that

 

[Adieu]

Re: Marshall preamp problem

Btw, did you notice the transistors have different last line numbers, whatever the hell that means?

Looks like 343, 736, and 252?

 

[GoldenVulture]

Re: Marshall preamp problem

Hello everyone, newbie here. I have a Marshall 8280 valvestate from the 90’s. The preamp has some obvious heat damage to some transistors. The factory installed an 4.6k resistor where the Marshall schematic shows a 8.2k should be. The transistors downline got smoked. The part numbers on the transistors is VN2410L. It’s a Motorola part number. I can’t find these damn things anywhere. Does anybody have any insight where I might be able to find these components? Thank you all for any help. Take care. -Ethan.

Here's a link to the data sheet for the VN2410L - http://pdf.datasheetcatalog.com/datasheet/motorola/VN2410L.pdf -

Looking for an Equivalent.

Mouser have these
- https://au.mouser.com/_/?Keyword=VN2410L-G -
- https://au.mouser.com/ProductDetail...GAEpiMZZMshyDBzk1/Wi%2bd6IwZRiMvUpm/2CqRAH08= -

 

[GoldenVulture]

Re: Marshall preamp problem

Btw, did you notice the transistors have different last line numbers, whatever the hell that means?

Looks like 343, 736, and 252?

They're production numbers and pretty much irrelevant.

 

[JMP/HBE]

Re: Marshall preamp problem

Somebody has bridged diodes across C3 & C25.

C3 should be a cap and its a resistor or am i missing something ?

That board is really messed up. I hope you don't plan on dumping alot into a solid state Marshall. That could be costly to fix.

 

[GoldenVulture]

Re: Marshall preamp problem

Somebody has bridged diodes across C3 & C25.

C3 should be a cap and its a resistor or am i missing something ?

That board is really messed up. I hope you don't plan on dumping alot into a solid state Marshall. That could be costly to fix.

Hmmm, modded/hacked.
Capacitors can come in resistor type packages. C1 looks like one. The pic is a bit dark to see C3 clearly but it could be like C1 in a package like this. The pinkish base colour the caps have appears to be missing from C3 though so you maybe right, it's a resistor.
[Eg]

The transistors and a couple of resistors look like they've been replaced [R82 & R 83 ]. It's a pretty bad soldering job

 

[NegativeEase]

Re: Marshall preamp problem

TS -some of that doesn't look factory

 

[DankStar]

Re: Marshall preamp problem

That don’t look right